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mmsalt
06-30-2019, 08:02 PM
I have a 55 2 door HDTP with the Newman Chassis using a 86 C4 suspension. Per CN calculator it looks as if my wheels and tires I'm leaning towards will fit. On the rear Im still undecided if I want 17 or 18 x 10 7" BS with 275 maybe 285 x 40 x 17 or 18. Will I regret going to 18 on the back and 17 on the front? Is a 285 too much for a 55 as it is I will have to remove the lower shock mount to install either way I go. Front is simpler 17 x 8 6" BS 245 45 17.

Any opinions on the NITTO NT555 G2?

Thanks
Mike

chevynut
06-30-2019, 09:41 PM
If the car is mini-tubbed you could go with a 295 tire max. A 275 should be an easy fit and is as big as you can go in a stock tub. The dogbones are really what limits the inside of the tire, but the tub is just about in the same place so you need some tire clearance. You only need around an inch and a half more.

The 86 C4 rearend is 62 1/4" wide at the wheel mounting surfaces. A 10" wheel with 7" BS has 1 1/2" positive offset. That makes the tire track 59 1/4" wide.

The outside of a pair of 275 tires would then be at about 70 1/8". That leaves about 5/8" from the tire to the fenderwell lip depending on the body dimensions and centering.

A larger diameter wheel will make it easier to remove them from the car. One trick I learned is to rotate the tire UNDER the disc when installing and removing. Also, use a shock that's longer than necessary so it will extend further, if you have the room, which you may not have with a Newman frame. Every little bit helps.

My Nomad has 18s in the rear with 295s and 17s in the front with 245s. I think they look good. When I get the final custom wheels they will probably all be 18s. I might go 20s just to piss off the old schoolers. LOL :D

9803

mmsalt
06-30-2019, 09:58 PM
CN Thanks for the response. The car is not mini tubed. Is 5/8 from tire to fender acceptable?

Custer55
07-01-2019, 02:27 PM
I have 90 Vette suspension on my 55 using 90 Vette wheels, 285/40/17 on the rear, 255/40/17 on the front. no issues with rubbing at all. I do have a 3/16 spacer on the rear to gain a bit of clearance on the inside, no spacer on the front. I wouldn't go any bigger than the 285 in the rear. In the front I had the stock size Vette tires, 275/40/17 and did not have any rubbing issues so you should be fine with 245's as long as the backspace is right. Not sure if 6" would be enough on an 8" wheel. Stock wheel is 9.5" with 7 7/16" backspace so the outside of the tire will be about the same place but the tire center line would be closer to the fender. I would go with more backspace if it were me. You can always move the wheel out with a spacer and longer wheel studs until you find the sweet spot that puts the wheel farther out without any rubbing.
I have Nitto NT 555 tires on mine (older version on the G2) I like mine. I think you will be happy with them.
Brian

chevynut
07-01-2019, 02:52 PM
Custer, the 86 C4 front and rear are 1" narrower than the 88-96 suspensions you have. That will affect the backspacing needed.

I typically like the tire outside width to be 67 3/4" or less if the car sits low in front. I'm not sure how Newman sets his ride height. With the 61" front end width of the early C4 and a 245 tire you need a wheel offset of 1 7/16" or more to keep the tire width at that limit. On an 8" wheel that's just under 6" backspacing. So 6" should work fine.

55 Rescue Dog
07-01-2019, 03:01 PM
Depending on your goal, I think a 245/45-17 is a little undersized, since the stock tires in a lighter/smaller C4 is either a 255/45-17, or 275/40-17 both of which have a load index of 98. The 245 is 95 load index. I don't think is quite possible to make the front of a 55 lighter than a C4. For me, I want maximum cornering traction on the front so I will go as big as possible on the front, which will determine what I go to on the rear. I might go with a square setup instead of staggered too. The biggest issue for me depending on wheel/tire combinations is how many tire choices are out there. On staggered setups with matching tires you are lucky to find one or two, if any. With something like a 255/45-18 there are like 48 different brands/models to pick from. Little front tires and big rears are a recipe for an understeering car plowing through the turns, which is safer, but not as fast/fun as a balanced car.

chevynut
07-01-2019, 03:27 PM
Depending on your goal, I think a 245/45-17 is a little undersized, since the stock tires in a lighter/smaller C4 is either a 255/45-17, or 275/40-17 both of which have a load index of 98. The 245 is 95 load index. .

A 95 load index tire can carry 1521 pounds. I don't think the front end of a tri5 is anywhere near 3042 pounds, even with passengers, so there goes your theory....again. :D

https://www.tirerack.com/tires/tiretech/techpage.jsp?techid=35


The BFG G-Force Comp-2 A/S tire in a 245/45-17 size is rated at 99 and can carry 1709 pounds EACH.

https://www.tirerack.com/tires/TireSearchResults.jsp?zip-code=80524&width=245/&ratio=45&diameter=17&rearWidth=255/&rearRatio=40&rearDiameter=17

And we all know that load ratings, like most everything, are conservative.

NickP
07-01-2019, 03:46 PM
5/8 is tight. Easiest thing to do, manually run the suspension through its articulations.

chevynut
07-01-2019, 05:38 PM
I don't know Nick....I think 5/8 is plenty if the body is centered and you have that on both sides. My calculations actually showed 11/16 but that's splitting hairs :). And he may be able to get more depending on the actual tire size, body width, etc. Also keep in mind that camber increases as the suspension compresses, so the top of the tire tilts inboard.

chevynut
07-01-2019, 06:19 PM
I forgot to mention that with the above measurements, the INSIDE of the rear tires would be about 48 7/16 wide using a nominal 275 tire. The stock wheel tubs are 46 1/2" wide inside. The dogbones are about 45 1/4" wide outside to outside in the CENTER of the dogbone between the bushing ends. That's 1" clearance from the 275 tire to the inside of the stock tubs which is about perfect since the tire leans inward at top.

My Nomad can handle a larger tire in front but only on the inboard side as the outside width is already at about the limit at 67 3/4". I think I have about 3/4" clearance from the tire to the frame there at full lock which should just barely fit a 275 tire. The narrowed rearend will handle a 345 tire but I'll likely never go that large. Now, wait for it, here comes RD's BS about how narrowing the rearend screws up the geometry, even though he doesn't know how. We've been through all of this nonsense before....more than once. :D

mmsalt
07-01-2019, 08:06 PM
Thanks for all the good information. The wheels will be special order due to the BS so I need to nail everything down before ordering.

Mike

Custer55
07-02-2019, 09:31 PM
Custer, the 86 C4 front and rear are 1" narrower than the 88-96 suspensions you have. That will affect the backspacing needed.

I typically like the tire outside width to be 67 3/4" or less if the car sits low in front. I'm not sure how Newman sets his ride height. With the 61" front end width of the early C4 and a 245 tire you need a wheel offset of 1 7/16" or more to keep the tire width at that limit. On an 8" wheel that's just under 6" backspacing. So 6" should work fine.

I missed that he has the 86 C4 suspension which is narrower so you are correct. An 8" wheel with a 6" backspace should be fine as the original wheels on an 86 were 16 x 8.5 with a 32 mm offset which works out pretty close to a 6" backspace.

55 Rescue Dog
07-04-2019, 02:39 PM
This thread got me to thinking, and shopping for what setup I was going to try and make work. I finally had the chance to put one of the front 17 x 9 wheels off my C5 with a 50mm offset/7" BS on the rear of my tubbed 55 C4. They could move almost an inch outboard on the tight side of my car. There are definitely a lot of choices going with a 245/45-17 tire, but to me they look kind of like 14 inch tires. So, since I want somewhere near a 27 inch tall tire, which also increases the contact patch, I need to use 18 x 9 inch wheels front, and rear to get the biggest selection of tire sizes, and compounds. I will probably have American Racing custom make one of the 5 spoke wheels in a 18 X 9 near a 34mm offset/6.34 inch backspacing. I will use something plus, or minus around a 275/40-18 front, and rear. It's going to be quite awhile, even though I've already had fun driving the car a lot in my head. I'm pretty sure my Nomad sized Tahoe would handle like shit if I narrowed the rear, and put some 13 inch wide tires on it. No BS, narrowing a C4 IRS would never ever enter my tiny brain.

Rick_L
07-04-2019, 05:02 PM
You do have a tiny brain. A narrowed suspension and bigger tires is going to result in the same width across the tire patch, just bigger tires.

And just how do bigger tires on the rear make the front tires slip? Or, for that matter, make the rear tires slip?

55 Rescue Dog
07-05-2019, 07:31 AM
You do have a tiny brain. A narrowed suspension and bigger tires is going to result in the same width across the tire patch, just bigger tires.

And just how do bigger tires on the rear make the front tires slip? Or, for that matter, make the rear tires slip?
It's a very complicated subject that you don't know much about either. Vehicle dynamics is an interesting subject, as to what the effects are between track widths, wheel offsets, geometry, and tire sizes. These links are just the tip of the iceberg. I'm going to rethink my tire/wheel choices. There is more to it than just wide tires.
http://www.tuneruniversity.com/blog/2011/04/wheel-tech-part-ii-size-matters/
http://dawsengineering.com/linked_files/technical_considerations_for_plus_sizing.pdf

Art Morrison refuses to narrow an IRS
https://www.hotrod.com/articles/1984-chevrolet-corvette-independent-rear-suspension/

55 Rescue Dog
07-09-2019, 06:46 AM
Another thing to consider about a tires load capacity. It's not just to support the weight of the vehicle at its static weight, but also the dynamic weight transfer of the vehicle during cornering, braking, and acceleration. The circle of traction is what it all comes down to. This article mentions some more things to consider when choosing tires for maximum performance.
https://motoiq.com/the-physics-of-tires/

chevynut
07-09-2019, 12:05 PM
I finally had the chance to put one of the front 17 x 9 wheels off my C5 with a 50mm offset/7" BS on the rear of my tubbed 55 C4. They could move almost an inch outboard on the tight side of my car.

First of all, you should be putting the wheels on with tires installed. The 50mm offset is going to make the track 59.31" with a late C4 which I believe is what you have. A nominal 275 tire at 10.83" is going to give you an outside width of 70.14". Most of these cars are around 71.5" across the wheelwell lips....mine are 71 11/16". That is unless your quarters are screwed up. So you should have 0.68" clearance between the tire and fenderwell lip on both sides. Go ahead and try to move them an inch. :D


There are definitely a lot of choices going with a 245/45-17 tire, but to me they look kind of like 14 inch tires. So, since I want somewhere near a 27 inch tall tire, which also increases the contact patch, I need to use 18 x 9 inch wheels front, and rear to get the biggest selection of tire sizes, and compounds.

What does a "14 inch tire" look like? You can get them in almost any diameter depending on series and width. There are plenty of taller tires in the 17 inch size. If you go with a 9" wheel you need at least a 275 tire in front to fit right. I thought you were supposedly a tire expert. :geek:


I will probably have American Racing custom make one of the 5 spoke wheels in a 18 X 9 near a 34mm offset/6.34 inch backspacing. I will use something plus, or minus around a 275/40-18 front, and rear.

Good luck with that. The outside of the tires are going to be 70.14" across and will surely rub unless you hack the fenders like you did on your camaro, or raise the front end a few inches. That will really help your center of gravity. LOL. :D


I'm pretty sure my Nomad sized Tahoe would handle like shit if I narrowed the rear, and put some 13 inch wide tires on it. No BS, narrowing a C4 IRS would never ever enter my tiny brain.

Your tiny brain can't even understand what your mouth is saying. What a stupid comment. How many narrowed Ford rears use wheels with deep offsets? How did that affect the tire track? I narrowed my C4 rear to 60" which is the same as a stock tri5. I did it partly to get a little more wheel dish, and partly to facilitate tire removal. But I understand that's hard for your tiny brain to comprehend. :p

chevynut
07-09-2019, 12:07 PM
Another thing to consider about a tires load capacity. It's not just to support the weight of the vehicle at its static weight, but also the dynamic weight transfer of the vehicle during cornering, braking, and acceleration. The circle of traction is what it all comes down to. This article mentions some more things to consider when choosing tires for maximum performance.
https://motoiq.com/the-physics-of-tires/

Blah, blah, blah. Your tiny brain must be working overtime today. Cars work fine with the tires that are available, and nobody really looks at load ratings. They're not going onto a dump truck. :D

chevynut
07-09-2019, 12:38 PM
I'm pretty sure my Nomad sized Tahoe would handle like shit if I narrowed the rear, and put some 13 inch wide tires on it.

What a stupid comment.....do you realize that a Nomad is the same size as your sedan? The only difference is the extended roof, replacing the trunk. The weight is only 200 pounds different due to the added glass and metal for the roof. How does the tire track change if you narrow the rearend and change the wheel backspacing to offset it? It doesn't.

chevynut
07-09-2019, 12:50 PM
It's a very complicated subject that you don't know much about either. Vehicle dynamics is an interesting subject, as to what the effects are between track widths, wheel offsets, geometry, and tire sizes. These links are just the tip of the iceberg. I'm going to rethink my tire/wheel choices. There is more to it than just wide tires.
http://www.tuneruniversity.com/blog/2011/04/wheel-tech-part-ii-size-matters/
http://dawsengineering.com/linked_files/technical_considerations_for_plus_sizing.pdf

Art Morrison refuses to narrow an IRS
https://www.hotrod.com/articles/1984-chevrolet-corvette-independent-rear-suspension/

So you post old, irrelevant articles and articles that babble on like you do and say nothing? I read the Hotrod article and it's almost 20 years old. I don't know who the guy is at Morrison who made those claims, but there's absolutely no data or analysis to support them. Lots of guys narrow C4 rearends including Tray Walden at The Street Shop. He routinely narrows them 4". The "tuneruniversity" article says essentially nothing useful.

You go on and on and make claims that something will get messed up if you do this or that, but you can't even fit a wheel to your car correctly, as I demonstrated. You never provide any numbers, data, or any analysis at all to support your claims. Your input is essentially irrelevant, especially after all the times I've proven you to be dead wrong.

Go ahead and "re-think" what you're going to do....again. Some day you might stumble on a solution that works. ;)

55 Rescue Dog
07-09-2019, 01:38 PM
BTW sir, I did have a tire on that wheel, but it was a 265/40-17. Stock front size for a Z06, but too short. It was only for a first time trial fit with just something I had available to get a rough idea. Thanks for setting me straight though. I feel much smarter now thanks to you CN.

chevynut
07-10-2019, 10:21 AM
RD, Since you don't seem to understand how a C4 IRS works let me explain what controls the camber curve. Apparently the guy at Morrison 20 years ago didn't understand this either.

The distance between the inboard u-joint and the lower strut rod inboard pivot point determines the angle between them and the resulting camber curve. You can draw it on a piece of paper using a compass if you don't believe it. With the halfshaft level, raising the knuckle causes the top of the knuckle to move inboard. Since the lower strut rod is pointed down and outboard, raising the knuckle causes the bottom of the knuckle to move outboard. The combination of these movements controls camber. The more the strut rod points downward, the more effect it has on the outboard movement of the bottom of the knuckle. It's simple geometry.

On the early (84-87) C4 Chevrolet put the inboard strut rod pivot pretty high, and the result was too much camber gain on those cars. This is an early (84-87) C4. Notice how high the inboard strut rod pivot is.

https://tech.corvettecentral.com/wp-content/uploads/2013/11/Suspension-Lead-Shot-1.jpg



In 1988 Chevrolet decided to reduce the camber gain on the IRS so they lowered the pivot point. Halfshafts and strut rods were left the same length, and the difference in rearend width is all in the knuckle, specifically the addition of a separate brake caliper mount. Here's a late (88-96) C4 rear, notice the lowered mounting point.

https://i.ytimg.com/vi/SqmXtmTL-j8/maxresdefault.jpg


You can change the camber gain to just about whatever you want to by moving that pivot point up or down. When you narrow a C4 rear you change the angle of the strut rod slightly (makes it steeper), so the camber curve is affected and you get more camber gain. I made my own brackets and modeled them after the late C4 suspension so my camber gain will be slightly more than a late C4 because of the narrowed rearend. I could have lowered that point further if I chose to do so to reduce the camber gain, but it's already less than an early C4 rearend so I didn't worry about it. Also keep in mind that I took 3" out of a 63" wide rearend which is less than 5% change in overall width. Halfshaft and strut rod length changed by about 8%. If I want to change the camber curve in the future for some reason, I'll make new brackets.

9805

9806

Now that you understand what effect narrowing a C4 IRS has on suspension geometry, maybe you'll lay off with the uneducated, snide remarks about my project and you won't be so annoying.

55 Rescue Dog
07-13-2019, 02:38 PM
That was a great explanation CN on narrowing a C4 rear. Sorry, but until you drive it hard into a corner, it is only an idea at this point, like mine. Everyone could use a test track.

chevynut
07-13-2019, 08:22 PM
That was a great explanation CN on narrowing a C4 rear. Sorry, but until you drive it hard into a corner, it is only an idea at this point, like mine. Everyone could use a test track.

You're welcome, but obviously not much of that technical explanation made it into your "tiny brain" or you wouldn't be making stupid comments like that.

scorpion1110
07-14-2019, 07:49 AM
You're welcome, but obviously not much of that technical explanation made it into your "tiny brain" or you wouldn't be making stupid comments like that.

Hey CN-

You have called RD "Tiny Brain" 4 times in this thread. You are starting to sound like that little kid on the playground who throws insults around trying to be cool.

You don't need to insult another member repeatedly to prove your point. Let your knowledge do that. Notice that RD didn't call you or your project names.

When you start insulting people all the time you lose your credability.

I think you are a smart guy who knows alot. I have gone to you when I have a question. You dont need to pick at people or their projects.

Scorp

markm
07-14-2019, 09:04 AM
Hey CN-

You have called RD "Tiny Brain" 4 times in this thread. You are starting to sound like that little kid on the playground who throws insults around trying to be cool.

You don't need to insult another member repeatedly to prove your point. Let your knowledge do that. Notice that RD didn't call you or your project names.

When you start insulting people all the time you lose your credability.

I think you are a smart guy who knows alot. I have gone to you when I have a question. You dont need to pick at people or their projects.

Scorp

He can sure dish it out but cant take it.

Rick_L
07-14-2019, 01:16 PM
RD started that by saying it first. That left the door wide open bouncing off the stops.

scorpion1110
07-14-2019, 04:09 PM
RD started that by saying it first. That left the door wide open bouncing off the stops.

Sorry. I miscounted the usage of "Tiny Brain" in the thread about tires for a 55 with C4 conversion.

I guess this thread just causes Tiny Brain-itis.

Scorp

carls 56 (RIP 11/24/2021)
07-14-2019, 04:18 PM
want this great site to grow, name calling not going to help.

Gmvette
07-14-2019, 06:06 PM
Yes I agree stop the snide remarks and stay with the useful sharing. One question. Is the vette suspension going to be any faster in a big car like the Nomad? I would think the much higher CG would see little benefit over a straight axle NASCAR type set up. The group 10 trucks that run in vintage racing are super quick in the turns and have the simplest suspension designs.

Rick_L
07-14-2019, 07:47 PM
I am no defender of Cnut's conduct but Rd's conduct is no better - they just insult each other and feed off each other's comments. To me it's when it extends to "innocent" members that they are truly out of line - and that happens.

On the benefits of IRS, where IRS has the most advantage is with marginal track or road surfaces.

Gmvette
07-15-2019, 04:46 AM
Rick are you saying the main advantage of independent rear is for bumpy road surface? Better ride? What about quickness thru a road course vs a NASCAR type solid axle? I would think the vette suspension was specific for low CG and less weight....maybe not?

Rick_L
07-15-2019, 05:32 AM
The IRS is less sprung weight (not necessarily lower total weight). This means the springs and shocks have an easier job of keeping the tires on the pavement and that's why they do better on rough roads - both for ride and performance. Lower C.G. height helps any suspension.

55 Rescue Dog
07-18-2019, 01:05 PM
Some IRS suspensions are great, especially on the newer cars. Chevrolet's first attempt in 1960 with the swing-axel Corvair might not of been so great, but they had it much improved by 1964 by using softer springs, a front sway bar, and a auxiliary traverse leaf spring. My first car was a yellow Corvair Syder Turbo, and that car was a blast to drive in its day. Too bad Nader killed a good car. The Yenko Stingers could spank a lot of cars back then, and still can. In 1965 they went fully independent with the same basic design as the C2, C3, and even the C4 isn't that much different. It changed dramatically on the C5.
As far as tires on a C4 Tri5, I would love to use a 255/50-17's which are 27 inches tall, and would look and work great. But there are only like 2 available tires in that size, and they are not that great. The only production car that used that size were the 94-96 Impala SS, and the demand is low in that size. I think any tire near 26 inches or less just looks too small on a big car. A 245/45-17 for example was a production size used on smaller cars like the 2004 Mustang, and GTO. The biggest selection of taller max performance summer tires seems to be mostly in the 18 inch sizes.

https://images43.fotki.com/v249/photos/5/54765/3837573/Corvairrearsuspension-vi.jpg

55 Rescue Dog
07-18-2019, 02:59 PM
Yenko Stinger. A 108 inch wheelbase car replaced by the Camaro with no IRS, and engine back to the front. Well now finally, along comes the Corvette C8.

https://www.youtube.com/watch?v=eTGayn3Y800

55 Rescue Dog
07-23-2019, 12:53 PM
I like the engineering explained guy's take on why big wheels, and low-profile tires are not always a great idea. On so many new vehicles they have become way to common, driven mostly by marketing, and looks over function. It never was an issue on older cars with bigger sidewalls, until they stated going below 50 series tires. 45 series tires are even showing up on truck/suvs too. Sidewalls that are too short shouldn't even be produced, or sold. Especially in the case of 25 series tire on a 26+ inch wheel with a one inch sidewall. Steering response probably goes out the window, since it would be like trying to make a big gyroscope change directions. Some wheels are starting to look like wheels on a train. The steam that blows the whistle, doesn't move the train.

https://www.youtube.com/watch?v=H6sPc9dFsGw&feature=youtu.be

55 Rescue Dog
07-24-2019, 06:46 AM
I'm starting to consider going to an even narrower tire instead a really wide tire, for many reasons beyond looks. I feel like maybe the 235/50-18 tires deserve consideration. There are over a hundred different models, and compounds of tires from like every manufacturer out there. They have fairly tall sidewalls with a diameter of 27.3 inches, 8 inch tread width, 9.5 section, 97-101 load range ratings. They are also cheaper, and can use a much lighter wheel, and probably ride better than a wide heavy wheel, with a short sidewall tire.

BamaNomad
07-24-2019, 06:57 AM
On what vehicle are you considering those tires/wheel, RD? I put 245/45-17 s on 8" wide wheels on my '57 Nomad I'm working on. Availability of optional tire brands/types is certainly a valid consideration.

55 Rescue Dog
07-24-2019, 08:26 AM
These will be for my 55 C4 project. I am now starting consider going against flow and go to narrower tires, instead of wide tire, which would be more for looks. It seems like a 235/50-18 setup might be a good choice for many reasons, plus a big selection of different tires. There are over a hundred different high performance tires in that size to choose from, and they have some really sticky ones. They have a fairly tall sidewall, at 27.3 inches in diameter, 8 inch tread, 9.5 section and up to a 101 load index. That size must be used on a lot of newer OE cars similar in size to get so many different models of tires. Plus they are cheaper, and use a lighter wheel, which helps the ride better, with less rotating mass, than a wide heavy wheel with a short sidewall tire.

BamaNomad
07-24-2019, 08:58 AM
The weight of the tire rubber is a big addition to the 'rotating mass', and the further from the center of rotation the larger that momentum is, so your 27.3" height adds momentum over a 26.5 or 26.8" wheel/tire height...

55 Rescue Dog
07-24-2019, 02:19 PM
I found this kind of interesting. The stock 1955 tire was a 6.70-15 that was 27 inches tall. With todays measurement it would be equal to a 170/90-15 that would also be 27 tall.
This link shows some other modern equivalents. From the side profile the car would resemble the original look, even with 18's if you squint a little.

https://www.automobile-catalog.com/tire/1955/342200/chevrolet_bel_air_2-door_sedan_265_v-8.html

Troy
07-24-2019, 02:24 PM
I see it was a 15" diameter, what was the width and offset?

55 Rescue Dog
07-24-2019, 02:33 PM
I see it was a 15" diameter, what was the width and offset?
That would be 6.7 inches wide across the sidewalls probably on a 5 1/2in wheel with zero offset I think. Probably only a 4 inch tread width. I did some OE repo Coker whitewall bias ply tires for a guy with his new looking, one owner 63 split window Vette that looked like it had the same tread width. And that was a performance car? In one direction anyway.

BamaNomad
07-24-2019, 09:26 PM
Original wheels for trifives were 5" wide (although there were some optional wagon wheels a bit wider I think)...

55 Rescue Dog
08-07-2019, 11:36 AM
Here are a few good pictures of wheels in the gallery of this site of wheels with a C4 chassis, used on tri-5, C1, and trucks. No idea of what the sizes are though. The maroon/white 56 2dr in the second picture is the best looking one of the bunch, and the blue/white 56.

https://www.rrframes.com/