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hutchenc
09-13-2015, 07:49 PM
I'll preface this with the fact that I've seen Lazlo's work in person and that he lives about 60 miles from me. I've also spoken to him about this a bit so I know where he stands on this :)

I have a '56 2 door hardtop. It has pretty much every damn bolt-on suspension part known to man and it still handles like crap in my opinion and I don't really like the steering (has a 500 box). I have a 550 to 600 HP 420ci SBC in her with a Muncie 4 speed so after looking into what kind of abuse a C4 rear will take, I think I'll stick with the solid axle (I have an 8.8 in her, that Lazlo modded for me :) ). I'd like to put in a parallel 4 bar I think. But the new leafs, poly bushings, and Viking shocks are fine for now.

Anyway, my car is far enough along now that I'm unwilling to take it all apart and remove the body from the frame. I wouldn't mind pulling the motor, tranny and front clip though, no biggie.

Has anyone here done a front subframe swap (preferable a C4) with just taking off the front clip? I don't have the welding experience to do it myself...this would have to be done by someone else (i.e. I'm not screwing around with this sorta thing...I'm paying someone to do it).

chevynut
09-13-2015, 09:02 PM
Chad, I don't know if we've discussed this before but I believe it can be done. I'm not aware of any of my customers doing it with the body on the frame, but I have had people ask me about it before. They just didn't go through with it.

Our clips weld on in front of the cowl body mount. We cut the frame further forward on the seamless version than we do on the 2-piece, because they're shaped differently. The seamless frames are about 5 1/2" tall at that point and the 2-piece are about 5 1/8" tall. We cut some wedges out of the frames to match them to our 5" tall main rail tubes, then we weld them back together and grind them smooth. That process would be a little more difficult with the body on the frame, but I think it can be done. We usually cut back to about the middle of the body mount or slightly further back on the seamless frames to get the contour right so the clip doesn't look scabbed on. We also install four 11 gauge reinforcement plates with 6 large plug welds on each side of the frame rail, then make the butt joint weld.

The most difficult part would be getting the alignment right without a jig, but that's how our clip customers do it. I usually recommend either building a quick temporary jig or using plumb bobs and tape measure to get it located correctly.

I would be interested in discussing this with you next time you're down my way. I would build a clip on a spare frame installed in my jig, then attach it to your frame. It would be cheapest if you stripped the car down by removing the bumper, all front sheetmetal, engine/trans, and steering box. I can cut the clip off with the suspension still on it. We could work with you so you could do it right here in my shop if you wanted to or you could trailer the car down.

Once the clip is installed the front suspension can be bolted on. If you have us build the engine mounts, the engine should bolt right up. Then you have to set up the steering shaft and you're pretty much there. All the stock sheetmetal should bolt right back on. I don't know how much of that I would want to do.

It would be nice to have a local car with one of our suspensions to try out.

Here's two of our frames with the frames matched to the clips, showing how we make it so the seam is barely noticeable. The one on the left is 2-piece and the one on the right is seamless. You can kind of see where the cuts are made but it's ground past them a bit.

http://www.trifivechevys.com/attachment.php?attachmentid=4973&stc=1

hutchenc
09-13-2015, 10:12 PM
Thanks for the reply Lazlo...I was under the impression that the frame cuts you made were aft of the firewall (meaning that this would be very difficult to do with the body on). I don't have a front bumper on right now so I guess that's one less step. I could probably sell all the other stuff on the car for a good clip of dough (tubular upper and lower arms, Heidt's spindles, 12.19" Wilwoods, sway bar, 500 box, rebuilt steering linkage etc).

Is there any reason I couldn't run C5 front brakes with a C4 front end? I know there are numerous places that make brackets for C4 to C5 brake conversions using stock GM rotors and calipers.

Next time I'm planning to be in FCO I'll give you a ring.

rustay56
09-14-2015, 04:19 AM
Hello Hutchenc, Ive just put a Morrison rear end in my 56 chassis (sorry I havent posted the pix yet but they're in my album) and have tubular A arms top and bottom,1 1/4 tubular sway bar,CPP drop spindle and 13in disc brake kit to go on.also power rack.I was hoping for an excellent handling and steering car,(not morrison or c4 standard) but not to far behind.I also fitted a center section. Now Im no chassis or suspension expert (far from it) but my theory is that its no good putting in stiffer springs ,sway bars front and rear and radial tires to increase handling and not do something to stop that poor old chassis from twisting and transferring all that new found movement into the body.Now my question, You obviously think the front end geometry in your car is wrong and by fitting a C4 front clip this will rectify it (not trying to do Lazlo out of a sale) just curious as we have very similar front ends and I thought I had spent wisely. Look forward to your reply.Sorry if this comes across abit arrogant its not my intention.:)

Regards Andrew.

chevynut
09-14-2015, 06:25 AM
Is there any reason I couldn't run C5 front brakes with a C4 front end? I know there are numerous places that make brackets for C4 to C5 brake conversions using stock GM rotors and calipers.

Using C5 front brakes would be a great upgrade. I believe they're 13". You use C5 rotors and calipers with the adapter brackets. I'm sure it's a lot cheaper than going aftermarket. I'll be around the house again starting about 9/25.

rockytopper R.I.P 5-13-2017
09-14-2015, 05:23 PM
I would be interested in the 500 box if you sale it.
Rocky

hutchenc
09-16-2015, 07:17 PM
rustay56,

I can't comment on the handling that you're going to be happy with because I think we're all expecting something a little different. I have driven a R&P tri-five with mostly stock but rebuilt suspension and frankly, it was so much better than the 500 box (which is what I have) I was pretty surprised...it still handled poorly though the steering was great. I like tight steering that requires some input...there's some slop in my completely rebuilt steering that I guess I just attribute to the linkage (also rebuilt)...I dunno. Now, the 500 box is substantially better than the 605 (I know this from experience), but I'm done changing things with the front end of my car at this point because nothing gets me where I want it to be and I think I'd just be throwing good money after bad.

All the other stuff...I dunno. The biggest difference anything has ever made on this car was simply rebuilding the steering linkage (badly worn out before I did that) and putting on a big front sway bar (1 3/8). The rest has made subtle differences in handling but I'm 100% confident that my mostly bone stock suspension '72 Camaro would just whip my tri-five in autocross so bad that one would probably assume the tri-five was completely stock or had an engine problem. The difference is that stark...it's so much so that when I have both the cars in working order (i.e. I'm not tinkering with something), I hardly drive the '56 because the Camaro is so much more pleasant and fun to drive.

I have good stuff on this car too...no ebay/chinese junk. Global West a-arms, delrin bushings up front, 500 box, Heidt's drop spindles, Hellwig sway bars (front and back), double adjustable Viking shocks, coil-overs up front, Global West rear leafs, poly bushings in back, poly body mounts, rear shock mount...everything. I run 17x8 wheels on all corners with 245/45/17's up front and M/T ET drags out back so I have good tires too...that's not the problem. There's literally nothing left to do at this point except try an R&P (which again, aint gonna happen).

I think for a cruiser, it's fine honestly. It doesn't wallow around corners or anything, it's just not very responsive. I didn't put a 420ci Dart SHP SBC in it to be a cruiser though.

I'm no mechanical engineer, but my assumption is that the geometry and mounting points of the front suspension just limit the ceiling on how far you can take the stock tri-five suspension...especially the front. If you think about it...the suspension is probably something designed in the very early 50's so hey, that was kinda a long time ago. Someone else would have to elaborate on the geometry and mounting points.

hutchenc
09-16-2015, 07:19 PM
rockytopper...it won't be any time soon so if you're in a rush, don't wait ;)

Also, I had to grind one corner of the box pretty heavily to clear my headers...I think the Dart SHP block (or the AFR 220 heads) may be a bit bigger than a stock SBC stuff because when I ran my 383 in the car, it fit fine. So, it aint perfect from an aesthetic point of view.

hutchenc
09-16-2015, 07:21 PM
Lazlo...yep, I think I would go with C5 brakes. Looks like an easy upgrade...lots of stock GM parts available vs the J55 stuff from the C4 (which looks to be pretty hard to find and expensive too). If it stops anything like my '05 GTO I'd be damn happy.

rustay56
09-17-2015, 04:43 AM
Hutchenc, Thanks for the reply and specs on your car.I know you said you were done throwing money at it but........
I lifted this article from an old super chevy magazine feature.It's from Doug Nordin from Global West
Camaros, Novas, and Chevelles are very popular amongst the ProTouring crowd but with the right parts you can get a Tri-Five to handle just as
well. Not a lot of people actually autocross their cars, so some basic upgrades is
all it takes to vastly improve a car’s street handling. At Global West, our parts are
designed for people who want bolt-on simplicity using the stock frame. We offer
tubular upper and lower control arms, sway bars, coil springs, leaf springs, and
steering boxes. Together, these parts substantially improve driveability and
cornering. For the best bang for the buck, upgrading the front control arms is
where it’s at. They add much more caster for improved stability and corner entry,
and change the camber curve for improved grip. Next on the list should be an
upgraded steering box. We offer a Borgeson 12.0:1 unit that has much better
steering feel and a quicker ratio than stock.

Dont know anything about borgeson box's but you need to try this or a rack then you exhausted all avenues and you can go to a C4 clip.It seems like you are so close and it's just the steering thats annoying you. Sell that 500 box to Rocky to offset some cost.If it doesn't work out you will always be able to sell all your front end parts off,they are good quality. Your not getting soft driving around in that 05 G.T.O. with the climate control on are you. :)

P.S If you have any trouble getting any little parts,clips ,switches or even literature for that G.T.O that might be nil stock in the U.S. I would be happy to assist,we have a large Holden dealership in my town......And I know a guy.:)

Regards Andrew.

rockytopper R.I.P 5-13-2017
09-17-2015, 01:45 PM
I don’t believe you will get any improved handling by going to an R&P. I also don’t know what the global west arms do as far as a front end geometry change. I myself believe drop spindles don’t help and probably make the dynamic geometry worse. I added CPP drop spindles first with stock suspension and got zero results. I say that also based on what Mark @ SC&C has told me and I could be wrong. But he wrote the book on how to make older cars handle http://www.amazon.com/How-Make-Your-Muscle-Handle/dp/1613251750/ref=la_B003NE2814_1_1?s=books&ie=UTF8&qid=1442523003&sr=1-1 . If you ever want to learn about suspension this guy is the one to talk to. Be ready to stay on the line when you get him started. He is very straight forward on what works and what don't.

I built this 1965 cutlass “seelink below” with all bolt on parts from him. If you believe what he says and I do, a stock trifive suspension and stock frame are far better in handling than any A-body GM sold in the 60’s and70’s. From my own experience I have to believe him. The frame on this cutlass is like a piece of spggatti compared to thetrifive boxed frame. The front end geometry had so much bump steer it was allyou could do to hold it in your lane on a bumpy road. I don’t even run high end shocks on thecutlass just a good set of belstiens. I have competed against c4 and c5 vets andArt Morison trifives etc in AX and we all run neck and neck on the course. SomeI beat some beat me. But my cutlass is now night and day compared to its formerself. I’m doing the same basic setup on my nomad project and hope to achieve similarresults. The only thing that Mark is offering over the other companies are theupper adjustable arms and taller ball joints see link. http://scandc.com/new/node/693 (http://scandc.com/new/node/693) .
Only time will tell if my assumptions are correct but Icould not be happier with how my cutlass handles. It also sports a CPP 500 box. I’ll just say I didn’t make PHR feature becausemy cutlass is worthy based on a quality build or show car it’s a hack job by comparison.It made it because they saw me competing in AX and kicking azz. That is what gottheir attention and the feature. Rick L,Cnut and I have discussed this before. The adjustable arm and taller balljoints allow modern alignment specs and also change the camber curve and rollcenter of the car. Basically it is mimickingwhat the C4 suspension already has built in. I.e. taller spindles etc…..
Another thing that I always see is that trifive folks thinkleaf springs need to go to 4 link. One of the top AX people in the country Mrs.Mary Posie won multiple championships in AX running a 70 Camaro with leafs,modern cars still use them today so they can’t be that much of a factor when itcomes to handling vs 4 link. I once readwhen you tune a vet for road racing the rear sway bars are so stiff it might aswell be a straight axle……. If you wantC4 up front go for it but I would not just add R&P I don’t think you willbe any better than you are now.

http://www.hotrod.com/cars/featured/1111phr-1965-oldsmobile-cutlass/ (http://www.hotrod.com/cars/featured/1111phr-1965-oldsmobile-cutlass/)


This is video of me on course in the cutlass @ GG. May not look like much but this is a very tight course. For reference the ls9 powered caddy on RS chassis that crosses behind me at the start ran a 57.9. The pros were running low 50's on this course.
http://vid282.photobucket.com/albums/kk243/rockytoppers1/IMG_2264.mp4

hutchenc
09-17-2015, 08:57 PM
Hutchenc, Thanks for the reply and specs on your car.I know you said you were done throwing money at it but........
I lifted this article from an old super chevy magazine feature.It's from Doug Nordin from Global West
Camaros, Novas, and Chevelles are very popular amongst the ProTouring crowd but with the right parts you can get a Tri-Five to handle just as
well. Not a lot of people actually autocross their cars, so some basic upgrades is
all it takes to vastly improve a car’s street handling. At Global West, our parts are
designed for people who want bolt-on simplicity using the stock frame. We offer
tubular upper and lower control arms, sway bars, coil springs, leaf springs, and
steering boxes. Together, these parts substantially improve driveability and
cornering. For the best bang for the buck, upgrading the front control arms is
where it’s at. They add much more caster for improved stability and corner entry,
and change the camber curve for improved grip. Next on the list should be an
upgraded steering box. We offer a Borgeson 12.0:1 unit that has much better
steering feel and a quicker ratio than stock.

Dont know anything about borgeson box's but you need to try this or a rack then you exhausted all avenues and you can go to a C4 clip.It seems like you are so close and it's just the steering thats annoying you. Sell that 500 box to Rocky to offset some cost.If it doesn't work out you will always be able to sell all your front end parts off,they are good quality. Your not getting soft driving around in that 05 G.T.O. with the climate control on are you. :)

P.S If you have any trouble getting any little parts,clips ,switches or even literature for that G.T.O that might be nil stock in the U.S. I would be happy to assist,we have a large Holden dealership in my town......And I know a guy.:)

Regards Andrew.

Andrew...I'm not getting soft with the GTO. I like how it handles and the fact that it's pretty damn fast while being really pleasant to drive. I had her up to 146 MPH the other day and it was like I was doing 65...it's a really stable car. It has under 50K miles...only thing it needs is a better shifter. The one GM put in it is garbage. Other than that, I might put in a bigger cam because...I can.

Anyway, I'll probably hold off on major modification to the rear of the '56 as it's not the problem (although, I'm considering a watts link for better lateral stability). It's not just the steering...I just have no confidence cornering in this thing. I still don't believe you can get a tri-five with bolt-ons to handle as well as a bolt-on A-body (which is essentially what that Olds is that rocky mentions), F-body, or even an X-body. And the reason those cars GW mentions are so popular isn't simply because of the way they look, the chassis is better than the tri-five or more people, at this point in time, would be road coursing and doing auto-x with tri-fives (but you hardly ever see them, and for good reason...their handling sucks and they're hard to get to the same point without a lot of work). If I were wrong, my nearly stock suspensioned '72 Camaro (it has front coil-overs, nothing else...also needs new bushings on the front suspension) wouldn't handle so much better than my '56.

I was shopping for C4 front suspensions last night. Hah!

rustay56
09-18-2015, 05:19 PM
[QUOTE=hutchenc;26935]Andrew...I'm not getting soft with the GTO. I like how it handles and the fact that it's pretty damn fast while being really pleasant to drive. I had her up to 146 MPH the other day and it was like I was doing 65...it's a really stable car. It has under 50K miles...only thing it needs is a better shifter. The one GM put in it is garbage. Other than that, I might put in a bigger cam because...I can.

Hutchenc, This is what you need. http://www.ripshift.com

Rocky, Thanks for the link to this. http://www.amazon.com/How-Make-Your-...2523003&sr=1-1 (http://www.amazon.com/How-Make-Your-Muscle-Handle/dp/1613251750/ref=la_B003NE2814_1_1?s=books&ie=UTF8&qid=1442523003&sr=1-1) . Ordered my copy this morning.I haven't checked the length of my G.W Upper Control arms against the stock arms as they stayed in the shipping box and went into storage until I need them.I was under the impression they were shorter and that would help in correcting the positive camber through suspension travel that these cars suffer from. If this is incorrect then should I be looking at upper ball joint spacers. ? I like your Cutlass,very cool:cool: I don't recall ever seeing one before.

Regards Andrew. My computer is having a "Hissy fit" and the font is all over the place.

Rick_L
09-18-2015, 06:09 PM
Here's my opinion on this discussion. I don't think there's a big difference in the potential of the suspension geometry between a 55-57 Chevy and most 60s cars. Obviously there are some great improvements that can be made to either one from stock with bolt on stuff. I think the biggest thing in comparing a 55-57 to a 60s/70s A or F body is the center of gravity. Either one is going to benefit from lowering but since the 55-57 starts higher and ends higher you never catch up.

I just don't see the difference between a modern box (500 or 670 for the 55-57 or a modified 800 for the 60s cars) vs. an R&P makes an appreciable difference. If you notice a difference, something is not right with the one that's not performing as well.

The other difference between these cars is that a 55-57 Chevy with stock suspension can't wear bigger than a 225 (or maybe a 235) tire on the front without rubbing or very restricted steering travel. This is probably the biggest benefit of an aftermarket frame or C4 conversion - you can run a 245 or maybe a 255 tire with these and that's huge IMO.

Length of the upper control arms is irrelevant. They need to be whatever length is required to have correct camber for the lower control arm length. Short control arms by themselves are not a good thing.

There is some advantage to a taller spindle height. How much is hard to quantify, typically it can only be measured by results on a specific course. This gives you a better camber gain curve, and keeps the tires square to the road when cornering and more traction. Taller spindles require shorter control arms, all else equal.

Another parameter is scrub radius. This is the distance from where a line drawn through the ball joints meets the ground vs. where the tire centerline meets the ground. A lot of scrub radius is a bad thing. A 55-57 has a 3.5* steering inclination angle (angle of a line through the ball joints) and when you put a wide wheel on the car the scrub radius is huge. This may be better on the A and F body cars but I don't know their numbers. A C3 Corvette has a 7* steering inclination angle. I don't know C4 or aftermarket suspension numbers but they are almost certainly 7* or more too (as well as having other dimensions that help), resulting in a small scrub radius. The reason that a big scrub radius is bad is that it's trying to steer the car due to mechanical leverage, either when the tires have good traction or when you hit bumps or holes.

Steering inclination angle is a function of how the spindles are built. You must change the spindle to change it.

Just some extra stuff to think about and see what applies to what you're thinking of doing.

hutchenc
09-18-2015, 10:02 PM
Rick...not sure how one can explain the massive difference in handling between a tri-five with every bolt-on under the sun and a 2nd Gen F body with nearly stock suspension. Massive difference is not an exaggeration so although I'm no geometry or suspension expert, my inclination is that there are major differences between the two chassis platforms outside of the center of gravity. I've had that '72 Camaro running 125 MPH and it felt miles more stable than my tri-five does at 70 MPH. I do have my caster at about 4.5 degrees positive btw (on my '56) with my aftermarket upper a-arms. My '72 Camaro has the factory a-arms. I dunno...maybe something is bent or just not right but I have no confidence driving this car fast even in a straight line.

Also, as far as R&P vs. 500 box difference. All I know is that the car I drove with the R&P vs my car with the 500 box and all new steering linkage was pretty noticeable. My 500 box has a dead spot in the middle and it is new...might have 1000 miles on it? The R&P was much more precise and responsive. Just my experience.

The rest you mention...yeah, spot on.

rockytopper R.I.P 5-13-2017
09-19-2015, 06:58 AM
I thank Rick pretty much nailed it. Obouviously my cutlass does not handle like a corvette nor will my nomad but the level it does handle at you'll thank your in a vet when behind the wheel. I am no expert or even spert in this subject matter. But Mark is. Give the guy a call sometime and be perpared for a long talk. Although Mark sales products he is a mechanical designer and car builder himself. Basically what I learned from him was & Rick also stated above is that proper handling is a combination of many things. The same improvements will give similar results on all these platforms but if any one thing is weak then the rest will suffer. My first car was a 55 2104dr, my first new car was a 1985 iroc z. The iroc had very good handling very close to the vet. When I called Mark I ask him will this make my cutlass handle like a iroc. His reply was no. It will be a little better. All I know is I'm a happy camper. So if my nomad handles anywhere where close I'll be happy.
Rocky

rockytopper R.I.P 5-13-2017
09-19-2015, 09:47 AM
Andrew I don't believe taller ball joints are available with any other arms other than the spc I mentioned. For reference the alignment settings I'm running 5 degree caster, -1 degree camber, zero toe. This is the medium agreesive settings that are specified with the setup.
Rocky

hutchenc
09-19-2015, 12:49 PM
Hey Rick...not to hammer this horse to death, but can you elaborate more on scrub radius? What the effects are when one has too much/too little? I'm running pretty wide wheels (for a tri-five) up front with 17x8's and 245/45/17 tires.

Rick_L
09-20-2015, 04:57 PM
Probably the biggest effect is increased steering effort. A large positive scrub radius will also make steering while braking difficult. In general it's going to work your tires harder any time you are steering. I don't think you could ever modify one of these cars to have negative scrub radius. Negative scrub radius will increase steering effort too.

The difference here is a suspension designed for a wide tire vs. a narrow tire.

Hard to say how much it means. I'd say down on the list compared to shocks, sway control, and camber gain. Thing is, modern solutions to all these fix the scrub radius too.

rockytopper R.I.P 5-13-2017
09-20-2015, 06:41 PM
I stand corrected apparently taller ball joints are available for stock arms or solid tube arms with stock ball joint mount.
https://www.howeracing.com/p-7929-howe-22304-fits-k6034.aspx

NickP
09-20-2015, 06:46 PM
Yup!

rustay56
09-21-2015, 04:09 AM
I stand corrected apparently taller ball joints are available for stock arms or solid tube arms with stock ball joint mount.
https://www.howeracing.com/p-7929-howe-22304-fits-k6034.aspx


Thanks Rocky. I've bookmarked it.

rockytopper R.I.P 5-13-2017
09-22-2015, 08:06 AM
There are a couple of threads on the other site that are discussing this. I believe the OPS description of the improvements associated with this simple change speak for themselfs. http://www.trifive.com/forums/showthread.php?p=1627233&posted=1#post1627233

Rick_L
09-22-2015, 08:18 AM
All we have there is one man's word that it was an improvement.

Do you have any links to some kind of a back to back test with quantifiable results, such as an autocross, etc?

I am not doubting that this is a good thing, it's just that it's hard to get a feel for the real results.

markm
09-22-2015, 09:12 AM
I was not driving in the 50s & 60s but my dad used to talk about driving his new PP 56 Belair 70 MPH plus on the highway all day long. Were they just tougher or have new cars spoiled us.

rockytopper R.I.P 5-13-2017
09-22-2015, 12:20 PM
All we have there is one man's word that it was an improvement.

Do you have any links to some kind of a back to back test with quantifiable results, such as an autocross, etc?

I am not doubting that this is a good thing, it's just that it's hard to get a feel for the real results.

Rick I’ve been preaching the message to you for over a year now and I don’t really think anything will convince you lol. If you need quantifiable data take a look at the AX results below or take a ride in the seat of my olds in the video below.
For the record my olds has a stock frame, spc lowering springs,spc arms with tall ball joints top and bottom, belstein shocks, 15/16 factory front sway bar, helwig pro-style rear sway bar and nitto 555 255/45/17R tires on all 4. You can see stock Chevelle’s, 442’s,gen one Camaro’s etc times in the list. They are very easy to spot they are way off pace of the leaders. You may also note my time against new vets camaros etc…. For the record I was on my 3rd year on same set of tires in2012 4th year in 2013. I progressively fell off pace year to year. I was 4 or 5 seconds off the pros pace in 2010 my first ever time on an AX course and my car had new tires. Bryan Finch won the class in his Detroit speed 1970 camaro full pro-touring machine. He turned pro the next year. If you watched the show “Are you faster than a redneck” series on speed channel then you would have seen him in action he is one of the top drivers in the country in pro-touring events today. Each year after my first I got worse and they all got way better year to year. Pro-touring exploded in the pro cat and cars become more race than street. Last couple of years the C10 trucks have beat everything on course. The course became even tighter than in the video below and my cutlass steering radius just want steer around the tight corners so I retired from doing this not as much fun anymore. For reference as a comparison against my times the old aka top heavy safari wagon was setting on an AM C4 frame and packing a 750 hp 6 speed so was the nomad. Only thing that ever bothered me was getting beat by wagons. Camaros and vets never bothered me their supposed to be faster lol.

The OP I posted stated as does everyone who makes this change that it makes a huge difference in stability (ie no more bump steer). In his case he is more or less stock and still running stockish alignment settings (minimal negative camber). That says a lot right there.

HIS WORDS Quote” I had my doubts that it would make much of an improvement. Figured it would be subtle or hard to notice at all. Nope I could tell a difference instantly.

Besides the more responsive steering the other thing that stopped was the subtle wandering the car still had even after adding extra caster from the CPParms a couple of years ago. I can quite literally drive with one finger on thewheel. Its that stable now.” End quote

I really don’t care if you become a believer or not to each his own…. But I did make a believer out of a C7 on my way to work this morning he was real surprised when he thought I’ll lose this old car around this next corner he was wrong.


Rocky

2010 GG AX results
http://i282.photobucket.com/albums/kk243/rockytoppers1/ax%20results%20spring.png
2011
http://www.lateral-g.net/forums/archive/index.php4?t-33841.html (http://www.lateral-g.net/forums/archive/index.php4?t-33841.html)

2012
http://www.lateral-g.net/forums/archive/index.php4?t-36103.html (http://www.lateral-g.net/forums/archive/index.php4?t-36103.html)

2013
http://www.lateral-g.net/forums/archive/index.php4?t-38671.html (http://www.lateral-g.net/forums/archive/index.php4?t-38671.html)


Just try to do a 4 wheel drift like seen here in your father’s olds, it isn’t going to happen. You may also note how flat my car stays in the corner that isn’t just sway bar doing that I can assure you.
http://s282.photobucket.com/user/rockytoppers1/media/IMG_2336.mp4.html (http://s282.photobucket.com/user/rockytoppers1/media/IMG_2336.mp4.html)

Rick_L
09-22-2015, 01:01 PM
Rocky you haven't been paying attention to me either - my car has tall spindles, no need for special ball joints.

Your lists don't mean much unless you can explain what the designations are. Hopefully that will make them mean something - but I still wouldn't know any details on any car.

rockytopper R.I.P 5-13-2017
09-22-2015, 02:25 PM
Rocky you haven't been paying attention to me either - my car has tall spindles, no need for special ball joints.

Your lists don't mean much unless you can explain what the designations are. Hopefully that will make them mean something - but I still wouldn't know any details on any car.

Forgive me Rick but I have never ever even heard you mention your car or even know what it is ever. I certainly never heard you mention that you run tall spindles. For the record I would like to see it some day.

In the list SM stands for street machine. This is the novice class like me none pro drivers and cars some highly modified some totally stock. The V stands for vendor or pro class. Brett V is the owner of ride tech they sponsor the event. They have a truck class now it dominates everything (NO LIMITS is leading it). They also have a hotrod class which is pre 50 cars I believe. The trifives fall in the SM class. The SS class is any American made car or truck newer than 1971 modified or stock. They are only allowed on track on Sunday the last day of the event. As I stated above the totally stock muscle cars are easy to spot on the list they are way behind us modified cars. Example I ran a 59 sec lap, they are 8 or 10 seconds behind me. Granted this difference is the sum of all my mods not just the tall ball joints, but just comparing my old 65 cutlass to the newer cars times pretty much speaks for itself that bolt on's can hold there own if setup correctly. The list of major suppliers at this event in no order are Ridetech, Detroit speed, no limits engineering, spectra performance, just to name a few. I will also add for the record that I run a 4l60 auto it is a handicap in this form of racing were you are on and off the throttle so even the numbers here are not comparing apples to apples. Most guys who are serious in the pro-touring world run standards. They are way better suited for this completion. I will also add that the Camaros have an advantage over us full size guys on these tight courses. That was ok cause all the pros for the most part ran Camaros they liked it that way. When they started letting newer all wheel and front wheel cars start playing and spanking the pros they now have all wheel and under 3000 lb classes to separate between them. The wickest car at the Fort Worth event is a morris mini 75 hp. He goes around course on three wheels rear tire off the ground and is one of the fastest guys at the event. Lot of fun to watch. They claim he has increased it to 125hp we will se how he does this year.

Taller spindles are great but in most cases are very $$$$. The taller ball joints make a big difference and a much cheaper option than tall spindles. Perhaps you have secrets on cheap tall spindle options for trifives? I always like learning new tricks will be happy to learn another. That is really all I have said all along. This simple mod makes a big difference and improvement. It is not the best or the fasted or best handling solution in town but it is cheap, affordable, and well worth money spent for a street car. I will get off my pedestal now.
Rocky

Rick_L
09-22-2015, 03:13 PM
Rocky my car has essentially a stock front suspension except for C3 Corvette spindles. These spindles are 1" taller than stock 55-57 spindles and they also have a 7º steering axis inclination compared to the stock 3.5º. To install them, you have to use a bushing in the tapered hole for the lower ball joint, as the Corvette has a big ball joint pin. The other thing you have to do is shorten the upper control arm about 3/4". This is due to the change in steering axis inclination angle and also to the extra height. The stock steering arms bolt up but you have to enlarge the bolt holes from 7/16" to 1/2". You use a C3 front brake or any aftermarket setup that can be put on a C3. Stock C3 rotor diameter is 12" as opposed to 11" on the Chevelle brakes many use. I have some aftermarket aluminum calipers for a C3.

For the upper control arms, I had a set of Concept 1 tubular arms for a 55-57. These use a stock ball joint. Turns out that it was a relatively easy fabrication job to move the ball joint mount inboard 3/4". I doubt many other tubular arms would be this easy to mod. It is one place where the SC&C arms should work nicely, providing you could shorten them enough (and you probably can).

The drawback to the Corvette spindles is they are not dropped, and I've never seen or heard of dropped spindles for a C3. I want my car low, so bottoming out potentially is a problem. One good thing about the C3 spindles is that they only move the wheel outboard from stock by the extra thickness of a rotor compared to a drum. This amount to 1/4" per side.

The car is still under construction, so I have no first hand knowledge of how it will handle.

Algoma56
09-22-2015, 05:30 PM
RickL,

Thanks for the reminder on the C3 spindles. I have a set here, as well as a couple of the A-body ones, and could re-purpose them on one of our projects. The tips on installing came back to me as we used a set 1970 full-size spindles to put discs on a buddy's 55 wagon 25-30 years ago. I don't remember using the 55's steering arms on those spindles, but do remember reaming out the arms to use the tie rods from the opposite side.

rockytopper R.I.P 5-13-2017
09-22-2015, 06:00 PM
Ricky That sounds like a good trick. It Will be interesting to see how it works out. I really like the fact that it does not move the wheels out to allow max tire fitment. If that setup works out I would certainly entertain an up grade in the future. What car you got to get low?
Thanks for info.
Rocky

Rick_L
09-22-2015, 06:48 PM
If the C3 spindle deal doesn't work out due to ride height vs. bottoming issues, I would probably go back to some Williams spindles with Wilwood or Chevy 12"-13"

The car is a 55 Bel Air 2 door sedan. I have most of the body work done. Rear suspension is pocket kit with Posies 3" drop springs, mini-tubs, Hellwig sway bar, and a 9" Ford from a Versailles with the OEM discs. All this is mostly complete too. Powertrain is a 95 Chevy LT1 and 6 speed. I have really slowed down on progress the last two years. I've been doing this deal forever, the LT1 was one of my first purchases and was current when I bought it. I have a couple of things to fix on the frame and it will be done. Next is panel fit on the doors etc. then paint. After that wiring and final assembly and interior. I am going to retire very soon and plan to get back with it. It's very tempting to go with LS power or even a big block but that would set back completion and cost me $$$. Maybe best to do those things on the next project. I also have a 67 Nova SS that was last redone in the late 90s. It has lacquer paint showing its age and has some of the original interior which is showing its age. So that will be my next project unless I get distracted and start on something else. The Nova currently has a mild 350 and a 200-4R trans. I see EFI or an LS for it.

Hutchenc, I know we've strayed from your original post - but I guess that happens.

hutchenc
09-22-2015, 09:27 PM
Sounds like a great car Rick. On the LT1 vs LSx power...you can make quite a nasty car with an LT1, some ported stock heads (from this guy: http://elliottsportworks.com/), and a mild roller cam. I wouldn't worry about it if you're happy with it. Seems like the biggest drawback of the LT1 is the Optispark.

Have you looked at the coil on pack retrofit kits for the LT1 where you can run an LS1 ECM to control the timing? http://www.eficonnection.com/eficonnection/24xLT1.aspx Not cheap or easy, but cheaper than a whole new LSx set-up and super, super cool!

rustay56
09-23-2015, 03:14 AM
All we have there is one man's word that it was an improvement.

Do you have any links to some kind of a back to back test with quantifiable results, such as an autocross, etc?

I am not doubting that this is a good thing, it's just that it's hard to get a feel for the real results.

Rick, Is using taller ball joints the same as lowering the upper 'A' Arm pivot point and if so, Isn't that what Shelby did to the early Mustangs to make them handle better.?

Regards Andrew.

Rick_L
09-23-2015, 04:32 AM
Not exactly the same but very close. It's also called the "Gulstrand mod" by some. The difference is with tall ball joints or tall spindles, you move the outer end of the control arm. The Shelby/Gulstrand mod moves the inner end. Usually with the Shelby/Gulstrad mod, the control arm shaft is moved forward too, for more caster. Results are similar but not exactly the same for the two methods.

rockytopper R.I.P 5-13-2017
09-23-2015, 07:48 AM
Sounds like a nice project Rick. Nothing wrong with LT1 6 speed. I fell in love with the tpi look before them. Still like the tall runners. Some folks dont.

chevynut
09-25-2015, 08:54 AM
Lazlo...yep, I think I would go with C5 brakes. Looks like an easy upgrade...lots of stock GM parts available vs the J55 stuff from the C4 (which looks to be pretty hard to find and expensive too). If it stops anything like my '05 GTO I'd be damn happy.

Chad, I happen to have a set of the J55 13" C4 brakes for the late suspension if you're interested. Give me a call or better yet stop by. We've got a couple of projects in the works.

chevynut
09-25-2015, 09:08 AM
I don’t believe you will get any improved handling by going to an R&P.

What you will get is a different "road feel" which is what a lot of guys are looking for. C4 racks are either 1.96 or 2.36 turns lock to lock. Also, with the front-steer setup the oilpan issues are non-existent. A steering system doesn't really change "handling" dynamics or geometry.


I myself believe drop spindles don’t help and probably make the dynamic geometry worse.

Dropped spindles do nothing but lower the CG of the car. I don't see how that can make anything "worse". Please explain.


I added CPP drop spindles first with stock suspension and got zero results.

And that's what you should have expected, since all it does is lower the car. In reality, you got a lower CG which should have improved the handling.


The adjustable arm and taller balljoints allow modern alignment specs and also change the camber curve and rollcenter of the car. Basically it is mimickingwhat the C4 suspension already has built in. I.e. taller spindles etc…..

Not true at all. We've discussed this before and just getting the "alignment specs" the same doesn't mean you have the same geometry. The only thing you're really changing is the caster, which is 6 degrees for the C4. You can get the rest of the alignment the same with a stock front end.

I'm betting the C4 lower a-arms are a different length than the stock tri5 a-arms, which changes the geometry. The spindles are taller, probably taller than the long balljoints. There are some things that you CAN'T duplicate with the stock frame, such as the anti-dive of the C4 suspension or the height of the upper a-arm attach points. The steering axis inclination is much larger for the C4 suspension, which you can't duplicate with bolt-on parts. All of that changes the geometry. The aluminum parts are lighter too.

There is no doubt that you can improve on the stock tri5 suspension with bolt-on parts. But you can't "duplicate" or "mimic" a suspension that has different length control arms and different angles on the mounting points. I have had customers who spent thousands on all the bolt-on stuff they could find only to be disappointed with the results. They went with the C4 setup and got what they were looking for.

chevynut
09-25-2015, 09:21 AM
This is probably the biggest benefit of an aftermarket frame or C4 conversion - you can run a 245 or maybe a 255 tire with these and that's huge IMO.

Yes that's true. I have 245 tires on my Nomad and could probably go larger as far as the frame interference is concerned.


Length of the upper control arms is irrelevant. They need to be whatever length is required to have correct camber for the lower control arm length. Short control arms by themselves are not a good thing.

I disagree. The lengths of the a-arms is what controls the motion of the spindle. A shorter a-arm will have a smaller arc causing more lateral motion of the balljoint.


Taller spindles require shorter control arms, all else equal.

Why? On any suspension the lower a-arm should be level at ride height. A taller spindle allows the upper a-arm to be in a different position than with a shorter spindle. If the upper a-arm is level at ride height, it will move the balljoint inboard with compression of the suspension. With the upper a-arm shorter than the lower one, the upper balljoint will move inboard more than the lower one, increasing camber which turns the tire into the turn, resulting in better traction. Some suspensions actually have the upper a-arm higher at the balljoint than at the frame pivot to increase this effect. The late C4 suspension does that.


I don't know C4 or aftermarket suspension numbers but they are almost certainly 7* or more too (as well as having other dimensions that help), resulting in a small scrub radius.

C4 SAI is 8.744 degrees for all years.

chevynut
09-25-2015, 09:33 AM
What I'd like to see someone do is use some suspension geometry software to compare the mods Rocky has done to the C4 suspension geometry in a dynamic situation. I know he can get the same "alignment" specs but that's not very meaningful.

And to me, AX times really don't mean squat ;). There are too many other variables like driver, brakes, engine, transmission, weight, tires, etc. And if looking at that, take a look at Kyle Newman's performance in AX with his C4 equipped tri5.

http://www.newmancarcreations.com/driving-fun/auto-cross.php

Rick_L
09-25-2015, 03:58 PM
Some suspensions actually have the upper a-arm higher at the balljoint than at the frame pivot to increase this effect. The late C4 suspension does that.

That's what I was referring to with the control arm length statement. When you increase the height of the upper ball joint, that's what's important, not the actual length of the control arm.

As for my statement about the control arm length shortening - if you increase the SIA, that moves the upper ball joint inboard. If you raise the upper ball joint, that also moves the ball joint inboard since it must lie on the SIA line. I am assuming in this description that the inner pivot for the upper control arm does not move. Obviously you could move it too - and that's what the Gulstrand/Shelby mod does. All this is in the context of starting with a given setup and making changes, not starting over.

I agree with you that autocross results are not everything because it's a tight low speed course. On the other hand, that's one thing you can do to put numbers to mods on a street driven car. May not be perfect or ideal, but at least it gives you numbers which you don't get with a "butt dyno".

rockytopper R.I.P 5-13-2017
10-30-2015, 07:42 PM
From the other site from the link I posted above about results of installing the taller ball joints and what they accomplish.

Quote "Stock tri-5 lower ball joints are positioned stud down. Installing a lower BJ with a longer stud will raise the vehicle ride height & create another issue due to the tri-5 short spindle height. The upper A arm will probably be pinned to the frame bumper. No need to figure the roll center with this configuration it is in the outfield.

When extrapolating suspension pivot points to determine roll center height a stock height 57 has an instantaneous center that does not cross the vehicle center line it intersects at the outside of the vehicle. This suspension design adds positive camber during bump, to the outside wheel during a turn & both wheels during braking.

A vehicle handles better when a loaded wheel changes to negative camber.

Using a stock height 57 with a 28" diameter radial tire which has a squat radius of 13" as an example: Installing a 1" taller ball joint in the upper control arm moves the instantaneous center across the vehicle vertical center line to the correct side of the vehicle. With this modification your front roll center is now 2.75" above ground, the suspension now changes to negative camber during bump, braking etc = a good handling vehicle that will roll a corner rather than plow through it..

Adding taller ball joints will effect camber setting with no effect on caster.

BTW: Upper ball joints experience more load force during hard braking than they get from suspension loading. The spindle acts as a lever through the ball joint trying to twist the upper control arm mount off of the frame.

Maddog
10-31-2015, 10:58 AM
Rocky my car has essentially a stock front suspension except for C3 Corvette spindles. These spindles are 1" taller than stock 55-57 spindles and they also have a 7º steering axis inclination compared to the stock 3.5º. To install them, you have to use a bushing in the tapered hole for the lower ball joint, as the Corvette has a big ball joint pin. The other thing you have to do is shorten the upper control arm about 3/4". This is due to the change in steering axis inclination angle and also to the extra height. The stock steering arms bolt up but you have to enlarge the bolt holes from 7/16" to 1/2". You use a C3 front brake or any aftermarket setup that can be put on a C3. Stock C3 rotor diameter is 12" as opposed to 11" on the Chevelle brakes many use. I have some aftermarket aluminum calipers for a C3.

For the upper control arms, I had a set of Concept 1 tubular arms for a 55-57. These use a stock ball joint. Turns out that it was a relatively easy fabrication job to move the ball joint mount inboard 3/4". I doubt many other tubular arms would be this easy to mod. It is one place where the SC&C arms should work nicely, providing you could shorten them enough (and you probably can).

The drawback to the Corvette spindles is they are not dropped, and I've never seen or heard of dropped spindles for a C3. I want my car low, so bottoming out potentially is a problem. One good thing about the C3 spindles is that they only move the wheel outboard from stock by the extra thickness of a rotor compared to a drum. This amount to 1/4" per side.

The car is still under construction, so I have no first hand knowledge of how it will handle.


C2 and C3 Vet spindles are Impala spindles (1959-64), the pre 69 have the same 7/16" steering arm size holes but drilling to 1/2" is no big deal. You can use 2" drop spindles if you want to go that route as the 58-64 Impala drop spindles will be the same as your Corvette spindles. CPP's latest version is probably the best but I'm not 100% on CPP quality.

chevynut
10-31-2015, 05:27 PM
When extrapolating suspension pivot points to determine roll center height a stock height 57 has an instantaneous center that does not cross the vehicle center line it intersects at the outside of the vehicle. This suspension design adds positive camber during bump, to the outside wheel during a turn & both wheels during braking.

Yes, that's because the upper a-arm pivot point is higher than the upper balljoint, because the spindle is so short.



Using a stock height 57 with a 28" diameter radial tire which has a squat radius of 13" as an example: Installing a 1" taller ball joint in the upper control arm moves the instantaneous center across the vehicle vertical center line to the correct side of the vehicle. With this modification your front roll center is now 2.75" above ground, the suspension now changes to negative camber during bump, braking etc = a good handling vehicle that will roll a corner rather than plow through it..

Not sure how he came up with those dimensions. Is there a diagram of this somewhere? I really wonder if just a 1" longer balljoint can do that. In order to move the instant center to the opposite side of the car the balljoint centers have to be further apart vertically than the a-arm shaft centerlines. I've never measured a stock tri5 suspension to see what the dimensions are.