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Josh57
01-17-2017, 04:50 AM
I am looking to upgrade the drum brakes on my 57 210. As far as i know everything is stock non power drum with the stock spindles. Looking at all of the kits there are way too many choices and i could really use some advice. It seems like you can spend a lot or a little depending on power upgrade / slotted vented rotors vs non / 1 piston caliper vs up to 6 / drop spindle vs stock. I am running what i was told are 15x6 rally rims from a 70s Camaro. they are a tight fit but don't rub as of now. I assume to keep them i would need to go with drop spindle kits to not move the wheels out or a zero offset kit. I am not against the drop as i do like the look of a lower front vs the rear and have been told the drop will help with handling. So i guess what I'm really asking is what do i NEED and what kits would you recommend. Not looking at a high performance race car type of set up and dont want to break the bank either but want safe and reliable. Thanks in advance for any advice.

Josh57
01-17-2017, 04:56 AM
Here are some pics of the rims im running now.

https://scontent-ort2-1.xx.fbcdn.net/v/t1.0-9/11866225_10204626032639042_8608054266867374133_n.j pg?oh=cca18cbcc9f4fcbd927ef0f8801c74ec&oe=5908E11F

Josh57
01-17-2017, 04:57 AM
https://scontent-ort2-1.xx.fbcdn.net/v/t1.0-9/11059533_10204626034319084_6234233002347952856_n.j pg?oh=2c0096b79c3e0956a6b6e6b66ff086c2&oe=59179E13

markm
01-17-2017, 06:19 AM
In the second gen Camaro world their are no 15x6 Camaro rally's, All second gen Z28s have five spoke 15x7 steel wheels , until the rubber baby bumper cars of the late 70s which had several versions of 15x7 alum wheels.

WagonWonder
01-17-2017, 06:30 AM
In the second gen Camaro world their are no 15x6 Camaro rally's, All second gen Z28s have five spoke 15x7 steel wheels , until the rubber baby bumper cars of the late 70s which had several versions of 15x7 alum wheels.

Wheel Code: AU, Part #: 3983045, Center cap part #: 3989479, Trim Ring part #: 3984524. Effective for 1970 through 1973 RS dropped in 1974

http://www.nastyz28.com/camaro/1971/blk71z-1.jpg

Josh57
01-17-2017, 06:55 AM
Yeah wouldn't surprise me to find out the rims came off of something else is there a good way to find out so i know exactly what i have?

markm
01-17-2017, 07:04 AM
Wheel Code: AU, Part #: 3983045, Center cap part #: 3989479, Trim Ring part #: 3984524. Effective for 1970 through 1973 RS dropped in 1974

http://www.nastyz28.com/camaro/1971/blk71z-1.jpg

Those are wheels that my 74 Z28 has on it, also used on 71/72 SS Chevelle. Came back in 77 on Z28 as std wheel. I have about 5 or 6 sets of them.

BamaNomad
01-17-2017, 07:08 AM
Your wheels appear to be 'after market' wheels... You could take one off the car, turn the wheel over, and WASH it on the back very well.. MOST wheels are identified somehow on the backside. Take a good photo and if you can't identify them, maybe one of us can help you.
I'm unaware that buying 'dropped spindles' is going to help you on the 'offset due to disk brakes'. If so, I certainly do not see the relationship there.

There are disk brake kits (without the drop) which do not offset the wheel mounting surface. This is one here which has some good characteristics, although I haven't used it personally.
http://www.ebay.com/itm/1955-1956-1957-1958-chevrolet-No-Offset-Front-Disc-Brake-Kit-/152382672877?vxp=mtr&hash=item237ab70fed

Note: I would prefer to use 'factory GM' parts if possible when doing such upgrades, and there are some options for using 60's or 70's GM disk brake parts for the upgrade (although I cannot comment on any wheel offset introduced).

chevynut
01-17-2017, 07:49 AM
Call me a skeptic but I'm not convinced the disc brake kits that use the stock spindle are truly "zero offset". I've never seen anyone actually measure them to prove the manufacturers claims. I'd like to see a measurement from the wheel mounting surface to the upper balljoint center before and after installing the kit. It's possible that the hub is zero offset when compared to the hub/drum of a stock car, but you have the thickness of the rotors which is typically around 5/16" or so. That increases the wheel mounting surface by 5/8".

Notice the rotors in that ebay kit appear to have an internal drum e-brake surface. I wonder what they're off. It looks like they're using the bigger late 60's Chevy calipers. And he has a RH caliper mounted on the left side :). By the way, the kit is from MBM and the brackets are available separately if one was inclined to assemble his own setup.

Has anyone actually measured these "zero offset" kits? I know the late 60's Chevelle rotors/hubs move the wheels out 7/8" PER SIDE for a total increase in wheel mounting surface width of 1 3/4". That can be a problem if you use wider tires and don't correct the offset with different wheels and I wouldn't recommend using any kits that use those hubs.

Rick_L
01-17-2017, 08:43 AM
The brake conversions that are called "zero offset" are not technically so, but are very close. The difference between them and stock is just the difference between the thickness on the wheel mount surface of a brake drum (1/8" per side) vs. the thickness of a rotor (around 1/4" to 3/8" per side). So the extra offset is 1/8" - 1/4" per side. These brakes use a hub that has the dimensions of a 61-68 full size Chevy hub which is the same as stock, and the rotor is the rear rotor from a 79 Trans Am.

The "usual" disc brake conversion uses the rotor from a 69-72 Chevelle or equivalent, which moves the wheel out by 7/8" per side. This will usually cause tire rub when turning, especially on a lowered car.

Most dropped spindle packages that use some kind of stock rotors move the wheel out 5/16" - 3/8" per side from stock. The Earle Williams spindles are close to stock. Aftermarket packages are close to this too, but before buying you should check with the mfr.

A 14" wheel that was made for disc brakes (both rally and aftermarket) will clear the Chevelle calipers rotors, the zero offset kits, and the stock rotor dropped spindle packages. Most aftermarket 14" wheels that were made from the mid 70s on are disc brake capable. Rally wheels were actually invented to be used with disc brakes, though not all are disc brake capable. This goes for 14" wheels with the 11" Chevelle rotor as well as 15" wheels with the 12" C3 Corvette rotor.

rockytopper R.I.P 5-13-2017
01-17-2017, 08:45 AM
Call me a skeptic but I'm not convinced the disc brake kits that use the stock spindle are truly "zero offset". I've never seen anyone actually measure them to prove the manufacturers claims. I'd like to see a measurement from the wheel mounting surface to the upper balljoint center before and after installing the kit. It's possible that the hub is zero offset when compared to the hub/drum of a stock car, but you have the thickness of the rotors which is typically around 5/16" or so. That increases the wheel mounting surface by 5/8".

Notice the rotors in that ebay kit appear to have an internal drum e-brake surface. I wonder what they're off. It looks like they're using the bigger late 60's Chevy calipers. And he has a RH caliper mounted on the left side :). By the way, the kit is from MBM and the brackets are available separately if one was inclined to assemble his own setup.

Has anyone actually measured these "zero offset" kits? I know the late 60's Chevelle rotors/hubs move the wheels out 7/8" PER SIDE for a total increase in wheel mounting surface width of 1 3/4". That can be a problem if you use wider tires and don't correct the offset with different wheels and I wouldn't recommend using any kits that use those hubs.

I posted this prior in my build thread but CPP is a true zero offset according to their tech REP. Now I have only mounted the kit on a drum hub during mockup. If it used the stock hub it would be pushed out by 1/8 each side due to the difference between drum and rotor thickness. I call and talked to the tech Rep to discuss this because I am very close on the inside with my setup. I ask him if this is the case. He verbally said no our hub is machined down to account for the difference between the drum and rotor and it is a true zero offset. There is a current post on other site the guy has a write up about his install using the Ebay version mentioned above installed on a 57. He claims it is zero offset. If it isn't it not going to push the wheels out anymore than 1/8 per side.

FYI willwood stock spindle brake kit pushes the wheels out .2 per side according to them.

Zero offset brakes kits fit stock spindles drop are not necessary to have zero offset kit.

Rocky

Rick_L
01-17-2017, 08:46 AM
CPP probably said their pitman arm wouldn't fail either.

rockytopper R.I.P 5-13-2017
01-17-2017, 08:50 AM
CPP probably said their pitman arm wouldn't fail either.

If you wish to throw them under the bus Rick we might as well started pulling out all the 500 gear boxes folks rave about as well....

royk
01-17-2017, 08:53 AM
I have the full size hubs with the Trans am rear rotors and Rick is correct in that the difference is the thickness of the drum vs rotor.

chevynut
01-17-2017, 09:04 AM
There is a current post on other site the guy has a write up about his install using the Ebay version mentioned above installed on a 57. He claims it is zero offset.

He said it doesn't look like it pushed the wheels out any based on looking at his tires. He said they were "about 3" from the fender" before an after. I'll bet he couldn't see a difference of 1/4" unless he measured it. I see no actual measurements quoted.


If it isn't it not going to push the wheels out anymore than 1/8 per side.

That's not "zero" so they shouldn't claim it is. 0.0000" is ZERO. :) :)

rockytopper R.I.P 5-13-2017
01-17-2017, 09:22 AM
Guys 1/8 inch is probably a closer tolerance range than the trifive was designed and built with 60 years plus ago. So zero with a plus minus tolerance of 1/8 or greater still equals zero LOL. At least that is how the lawyers that work for our firm would present it. Another words it is close enough for government work lol......

chevynut
01-17-2017, 09:37 AM
Guys 1/8 inch is probably a closer tolerance range than the trifive was designed and built with 60 years plus ago. So zero with a plus minus tolerance of 1/8 or greater still equals zero LOL. At least that is how the lawyers that work for our firm would present it. Another words it is close enough for government work lol......

But 1/8" matters to a guy whose tire is 1/8" from the fender before the modification. It's not hard to measure the actual offset accurately, and imo they should. :)

BamaNomad
01-17-2017, 10:00 AM
But 1/8" matters to a guy whose tire is 1/8" from the fender before the modification. It's not hard to measure the actual offset accurately, and imo they should. :)

The poster on the 'other forum', did measure using a tape measure from the tire to a plumbed level dropped from the fender lip. He did this with the stock drum system and again iwth the updated disk system using the same wheel/tire and measure ~3 inches. I also agree with Rocky that a 1/8" precision is about as good as it's going to get with these vehicles.. (there can be more variation than that from one car coming off the factory line to the next). Of course precision measures of the actual mechanical parts differences can result in closer values of the change (as Rick points out)...

Josh57
01-17-2017, 10:19 AM
So are drop spindles not the way to go? i do like the idea of lowering the front end a bit but would my tires be more likely to rub?

chevynut
01-17-2017, 10:24 AM
Bamanomad, my point was that if a guy had 1/8" clearance between his tire and fender, and he bought a kit that was supposed to be "zero offset", he wouldn't expect the tire to rub. If it did, would that be acceptable? I think not.

You guys keep talking about these vehicles not having 1/8" precision...that may be true, but that's not the point. You can measure the brake offset much closer than that. So they should imo and not advertize it as "zero offset" if it's not. Measuring from the spindle somewhere to get the actual offset isn't that hard. If everything you bought for these cars had +/-1/8" tolerance it would be crap.

If my frames were +/- 1/8" for wheelbase, centering of suspensions, or axle squareness in the frame, I would think it would be unacceptable. We keep our tolerances to +/- 1/16" or less for just about everything we do on them. If we're more than 1/2 of a string-width off-center we fix it.

A guy with 3" of clearance between tire and fender doesn't care about wheel offset. Some guys might.

chevynut
01-17-2017, 10:38 AM
So are drop spindles not the way to go? i do like the idea of lowering the front end a bit but would my tires be more likely to rub?

IMO if you want a 2" drop, go with dropped spindles. If you only want 1" you could get by with lowering springs. The front suspension only has 3 1/2" of travel, so once you start dropping it 2" with lowering springs you're probably going to bounce off the a-arm bumper a lot.

What size tires do you have on front, and what is your wheel offset? Anytime you lower a car you're more likely to have rubbing problems, but not necessarily. If you lower the car 2-3" and your tires are more than about 67.5" wide on the outside to outside, you're getting close to rubbing on sharp turns at full lock. Keep in mind that if a suspension compresses on a sharp turn, it's just like having a front drop.

Josh57
01-17-2017, 11:52 AM
I will have to measure everything tonight I'm not set on lowering the car i do like the way it looks but i was under the assumption that by going with drop spindles i would eliminate moving the tires out any ensuring they would not rub. How exactly do i measure wheel offset I am quite new to all of this.

chevynut
01-17-2017, 12:29 PM
I will have to measure everything tonight I'm not set on lowering the car i do like the way it looks but i was under the assumption that by going with drop spindles i would eliminate moving the tires out any ensuring they would not rub.

It all depends on tire size and wheel backspacing/offset.


How exactly do i measure wheel offset I am quite new to all of this.

Offset is how far off -center the wheel mounting surface is:

http://www.tirerack.com/images/wheels/tech/offset.gif



Backspacing is the measurement from the inboard side of the wheel flange to the mounting surface:

http://cdn.app.compendium.com/uploads/user/3830be5e-cdd1-486f-a4e4-308bac9591c9/81835cba-0bc8-4736-91a6-e70e91c33213/Image/3f9a984b44fe12ef57cb8f2207810d4f/measure_backspace.jpg

A 7" wheel is actually 8" wide at the outside of the flanges. Wheel width is specified at the INSIDE edge of the flanges. So a zero offset 7" wheel would actually have 4" backspacing, not 3.5". That's because backspacing is measured outside of the back flange.

Josh57
01-18-2017, 05:10 AM
Took some quick measurements last night and found i am real close to 68" from outside the tires. Front tire size is 235 60R15. I like the idea of dropping 2" so i am hoping to go with a drop spindle as well. I have seen some kits actually state they move the wheels in 1/4". I didn't get a chance to measure the offset or backspacing of my rims yet but hope to have time tonight.

mikes55
01-23-2017, 06:46 PM
I have a brand new set of 11/2 inch lowering springs and brand new Monroe sense-trac nitrogen gas filled front shocks that go with the springs for $100.00.

Josh57
02-07-2017, 06:24 AM
https://www.danchuk.com/ItemForm.aspx?Item=15256&ReturnURL=/danchuk1.aspx?Id=5efe2ad6-7e07-4599-9469-03029b86133b&Category=5efe2ad6-7e07-4599-9469-03029b86133b

I am looking at going with this kit to make sure i don't move my wheels out any. Thoughts?

BamaNomad
02-07-2017, 06:44 AM
That one moves the wheels IN about 3/16"... Don't forget that you can have issues with rubbing on the INSIDE of the tire as well... with big wheels/tires... 235/60-15 sounds big to me. Measure twice.. Cut once.. :)

chevynut
02-07-2017, 06:59 AM
Did you ever get a chance to measure your wheel offset?

Bihili
02-07-2017, 08:31 AM
I am looking to upgrade the drum brakes on my 57 210.

First thing I would check is the vacuum on your engine. Why???

If you are going to upgrade to a vacuum booster on power disc brakes you need at least 18 lbs. of vacuum for the booster to function properly.

If you have a radical cam and low vacuum then a hydoboost may be the solution but you need a power steering pump for the hydroboost.
However upgrading your steering and braking is a good thing.

markm
02-07-2017, 09:10 AM
First thing I would check is the vacuum on your engine. Why???

If you are going to upgrade to a vacuum booster on power disc brakes you need at least 18 lbs. of vacuum for the booster to function properly.

If you have a radical cam and low vacuum then a hydoboost may be the solution but you need a power steering pump for the hydroboost.
However upgrading your steering and braking is a good thing.

I agree, unless you have a good factory PB system like my 67 SS 350. It worked good at 14 Inches of vacuum , but when I switched to a Cam that had 8 at idle I almost hit the mailbox backing out for the initial test drive. Today same car with a Duntov 30-30 they work fine and I believe I have about 12 inch's of vac.at idle. Most aftermarket small stuff probably needs all it can get but I doubt even they need 18 pounds.

KNUB1945
02-23-2017, 12:52 PM
I would like to convert my 55 210 to disc on the front but I'm not sure the 14" American torq thrust d made in the 60's will clear the calipers or not. Anybody know?

markm
02-23-2017, 01:07 PM
Have any buddies with a first gen Camaro or 68-72 Chevelle , Nova with disk, if they fit those they will fit a 55-57 converted, Factory wheel were brake specific in that era, so were many aftermarket.

KNUB1945
02-23-2017, 01:21 PM
Thanks, markm

markm
02-24-2017, 07:16 AM
If those wheels clear disk brakes, you should have no issues with a Chevelle rotor on a 56.

chevynut
02-24-2017, 07:25 AM
KNUB1945, the only issue with the Chevelle rotor is that it pushes the wheel out by 7/8" per side. If the car is lowered, or if the suspension compresses significantly while turning sharp, it could cause rubbing of the tire against the fender. If you have a stock-height car it will typically not be a problem, but it looks weird to me to have the tire nearly even with the fender lip. Again, that depends on how big of a tire you have, and the wheel offset. If you're going to buy a disc brake kit anyhow, get one that doesn't push the wheels outboard. They make near-zero offset disc brake kits for stock or dropped spindles.

KNUB1945
02-28-2017, 07:57 AM
KNUB1945, the only issue with the Chevelle rotor is that it pushes the wheel out by 7/8" per side. If the car is lowered, or if the suspension compresses significantly while turning sharp, it could cause rubbing of the tire against the fender. If you have a stock-height car it will typically not be a problem, but it looks weird to me to have the tire nearly even with the fender lip. Again, that depends on how big of a tire you have, and the wheel offset. If you're going to buy a disc brake kit anyhow, get one that doesn't push the wheels outboard. They make near-zero offset disc brake kits for stock or dropped spindles.

My plan is to use 1979-81 firebird rear rotors and 1964 impala hubs with 1969 Chevelle calipers.Do you see any problems with this setup?

Rick_L
02-28-2017, 08:27 AM
60s built 14" wheels are likely not going to fit. Wheels made starting in the mid 70s possibly will.

A 14" Chevy Rally wheel made for disc brakes will clear the Chevelle rotors/calipers. Aftermarket wheels made with the same style on the backside will also fit. I think this means 70s and up wheels.

BamaNomad
02-28-2017, 08:39 AM
The '68-69 Camaro/Nova 14" disk brake wheels will clear, whether Rallye or not. by 1972, I think almost any Chevy 14" wheel will clear the brakes.

Re your '60's 14" Torq Thrust... no idea, but I'd suggest trying them on any late 60's or early 70's disk brake Camaro or Chevelle etc.. to ensure they clear.

markm
02-28-2017, 11:06 AM
Sure glad people pay so much attention on here.


Have any buddies with a first gen Camaro or 68-72 Chevelle , Nova with disk, if they fit those they will fit a 55-57 converted, Factory wheel were brake specific in that era, so were many aftermarket.

All Camaros are disk brake 70 up, Chevelle/ Monte 73 up, Nova 75 up prior to these dates drum was std. and disk was an option.

chevynut
02-28-2017, 11:13 AM
My plan is to use 1979-81 firebird rear rotors and 1964 impala hubs with 1969 Chevelle calipers.Do you see any problems with this setup?

I don't know what the 64 Impala hubs do to the wheel mounting width. That would be my only concern. The calipers are fine, as long as you can find the appropriate mounting bracket. Are you lowering the car?

Rick_L
02-28-2017, 11:19 AM
The so-called "zero offset" kits use a 61-68 full size Chevy hub, with a Trans Am rear rotor, and the Chevelle caliper.

markm
02-28-2017, 12:20 PM
I don't know what the 64 Impala hubs do to the wheel mounting width. That would be my only concern. The calipers are fine, as long as you can find the appropriate mounting bracket. Are you lowering the car?

I don't think they do anything to it, until you add thickness of rotor. If I remember correctly people used to use them with stock drum brakes to upgrade to tapered roller bearings. The T/A rear rotor is designed to be a rear disk rotor. I have always wondered if its thick enough for front use.

Rick_L
02-28-2017, 12:51 PM
If the caliper fits, it's the same thickness as the Chevelle rotor.

markm
03-01-2017, 05:55 AM
If the caliper fits, it's the same thickness as the Chevelle rotor.

I guess my memory is a little foggy on these, I only had one in my time. .980 vs. 1.00

Rick_L
03-01-2017, 03:26 PM
,020" doesn't mean much since there's around 1/2" of pad between the pair.

KNUB1945
03-02-2017, 09:41 AM
I have the full size hubs with the Trans am rear rotors and Rick is correct in that the difference is the thickness of the drum vs rotor.

Which calipers did you use? year and model?

KNUB1945
03-02-2017, 09:51 AM
I don't know what the 64 Impala hubs do to the wheel mounting width. That would be my only concern. The calipers are fine, as long as you can find the appropriate mounting bracket. Are you lowering the car?

no,I am not lowering the car!

KNUB1945
03-02-2017, 09:57 AM
I have the full size hubs with the Trans am rear rotors and Rick is correct in that the difference is the thickness of the drum vs rotor.

I forgot to ask what are the hubs off of that you are using?

KNUB1945
03-02-2017, 10:03 AM
Your wheels appear to be 'after market' wheels... You could take one off the car, turn the wheel over, and WASH it on the back very well.. MOST wheels are identified somehow on the backside. Take a good photo and if you can't identify them, maybe one of us can help you.
I'm unaware that buying 'dropped spindles' is going to help you on the 'offset due to disk brakes'. If so, I certainly do not see the relationship there.

There are disk brake kits (without the drop) which do not offset the wheel mounting surface. This is one here which has some good characteristics, although I haven't used it personally.
http://www.ebay.com/itm/1955-1956-1957-1958-chevrolet-No-Offset-Front-Disc-Brake-Kit-/152382672877?vxp=mtr&hash=item237ab70fed

Note: I would prefer to use 'factory GM' parts if possible when doing such upgrades, and there are some options for using 60's or 70's GM disk brake parts for the upgrade (although I cannot comment on any wheel offset introduced).
do you have a list of the parts and they are off of ?

royk
03-02-2017, 10:28 AM
I used the d52 style like the '72 monte carlo's used, my hubs were from 1965 full size impala