negative cambered rear ends

[CamaroAJ]

do any of you guys run a negative cambered rear diff? i have been thinking about the rear diff i want to get for my car. since the car will see more street time than track time will it hurt anything other than tire wear? the car will get pounded on autocrossing about 12 times a year and as many track days as i can get too so i am more concerned about handling than tire wear. anyone with some experance with this one?

edit: this will be on a '69 camaro with a 3-link. thinking about -.5* with a little bit of toe in.

[Bryce]

With out a full floater designed to be cambered it will load the bearings and wear them out faster. Nascar does what you are talking about.

[Bulletpruf]

Doing the same thing on my Javelin. Looks like 1 deg. of negative camber on the back is about right for a street/track car. Any more than that and you've got to worry about excessive tire wear on the inside.

Folks at Speedway Engineering seem to be the best out there if you want a full floater 9" built to order. Their cambered rears are about $250 more than the non-cambered.
Scott

[BADDRIDE II]

Attachment 49487Attachment 49486
Attachment 49485
I brag about THE GMR every chance I get. I purchased a Fabricated Housing Full Floater Rear from Jason at THE GMR and have never seen anything like it. I shopped ALL other full floater manufacturers and nothing was as specifically designed for AutoX/track/daily driving like the GMR kit. If you will be running high horsepower and big brakes than GMR's kit is for you. It is a lot more pricier than all others.........but you get a lot more. I think anyone looking to purchase a Full Floater rear should check them out before purchasing a Floater setup. TheGMR.com or contact Jason at [email protected]

[BADDRIDE II]

Attachment 49488

This is some nice stuff! The drive plate is 35 spline and drives on a smooth shank area on the 17-4 stainless wheel studs (unlike others that drive on the wheel stud threads.....which is against everything we have been taught about shear points!) VERY STRONG!

[TheJDMan]

Speedway Engineering, Moser, Howes and others have been supplying floating rear ends for NASCAR and other sportsman class racing for over 25 years. Any of these manufacturers can supply a 9" floating hub rear end with negitive camber settings for not a lot of money. NASCAR and sportsman racing put the same if not more stress on hub components as any track day or autocross.

[BADDRIDE II]

Speedway Engineering, Moser, Howes and others have been supplying floating rear ends for NASCAR and other sportsman class racing for over 25 years. Any of these manufacturers can supply a 9" floating hub rear end with negitive camber settings for not a lot of money. NASCAR and sportsman racing put the same if not more stress on hub components as any track day or autocross.

Maybe so, but I would not run those "circle track" drive plates on anything with real horsepower and a sticky tire......if the light duty "circle track" 24 spline driveplate does'nt strip out first.....surely the studs will shear since these "circle track" driveplates drive on the thread of the stud (can we say big no no). You are also limited to smaller rotor sizes as well since NASCAR/etc. do not run Big Brakes. I have seen a few one off steel rotor adaptors made in attempt to run larger rotors on these "circle track" kits.....but I do not like all that additional rotational weight eating up hp and throwing entire wheel assembly out of balance. I am sure the "circle track" kits are fine on lighter duty applications, but for the modern day High HP muscle car that may dump the clutch with large sticky tires at the track or even a nice patch of concrete....I would recommend NEWER TECHNOLOGY......lets be realistic, the first gen small block chevy is great too and has been around a long time.....but now the LSX is available! Check out pic of 24 spline circle track drive plate below.

Attachment 49720

[HarleyR]

Maybe so, but I would not run those "circle track" drive plates on anything with real horsepower and a sticky tire......if the light duty "circle track" 24 spline driveplate does'nt strip out first.....surely the studs will shear since these "circle track" driveplates drive on the thread of the stud (can we say big no no). You are also limited to smaller rotor sizes as well since NASCAR/etc. do not run Big Brakes. I have seen a few one off steel rotor adaptors made in attempt to run larger rotors on these "circle track" kits.....but I do not like all that additional rotational weight eating up hp and throwing entire wheel assembly out of balance. I am sure the "circle track" kits are fine on lighter duty applications, but for the modern day High HP muscle car that may dump the clutch with large sticky tires at the track or even a nice patch of concrete....I would recommend NEWER TECHNOLOGY......lets be realistic, the first gen small block chevy is great too and has been around a long time.....but now the LSX is available! Check out pic of 24 spline circle track drive plate below.

Attachment 49720

How many miles were on the driveplate pictured? These things do wear out....and eventually need replacing.You would have to be a complete moron to not purchase the correct wheel studs so insure the plate does not ride on the threads.Dont ignore the fact that people do not always purchase the right parts for their application... Just because it says NASCAR does not mean its able to handle everything, most circletrack sportsman cars are under 500 hp and very rarely do drag strip launches...A grandnational style driveplate like speedway engineering sells handle 900RWHP 3500 pound cups cars on ovals and road courses every sunday.... although they do happen, failures are very rare(I've been doing it for over ten years and have never had an axle failure) You would also have to have serous problems to have something out of balance.... perhaps a rotor thats not mounted to the hat correctly..or if its a floating set up a tolerance issue.. Im not sure how much more rear brake you would need... 11-12 inch rear rotors seem to work well...

[BADDRIDE II]

How many miles were on the driveplate pictured? These things do wear out....and eventually need replacing.You would have to be a complete moron to not purchase the correct wheel studs so insure the plate does not ride on the threads.Dont ignore the fact that people do not always purchase the right parts for their application... Just because it says NASCAR does not mean its able to handle everything, most circletrack sportsman cars are under 500 hp and very rarely do drag strip launches...A grandnational style driveplate like speedway engineering sells handle 900RWHP 3500 pound cups cars on ovals and road courses every sunday.... although they do happen, failures are very rare(I've been doing it for over ten years and have never had an axle failure) You would also have to have serous problems to have something out of balance.... perhaps a rotor thats not mounted to the hat correctly..or if its a floating set up a tolerance issue.. Im not sure how much more rear brake you would need... 11-12 inch rear rotors seem to work well...

Not sure exactly how many miles, but definitely one too many wouldn’t you agree! Does not sound like it is a surprise to you that these 24 spline CIRCLE TRACK drive plates fail? You are not the first to step up on PT.com and testify to this weakness. As for your testament of these 24 spline CIRCLE TRACK drive plates wearing out….it would not surprise me since there are only 24 splines….had it been 35, this would not be a consumable…...

I like that you agree with me on the drive plate needing to ride/thrust on a designated shank area on the wheel studs vs. on the wheel stud thread itself…..but you act as if no one does this? First off I can think of a few people that follow these “Floater Threads” pretty closely that may take offense to your “Moron” comment, since that is what they purchased with their CIRCLE TRACK kits . And you cannot blame them, since even these CIRCLE TRACK kit distributors even showcase them on their sites with this type design and include in their kits (which may be fine for CIRCLE TRACK…but NOT DRAG or High HP PRO TOUR.

As for speedways drive plates handling 900RWHP in 3500# cars……until these drive plates NO longer experience REGULAR failures…..I do not agree that they can handle it, nor are they a PRO TOUR car in comparison. I would have to go out on a limb and say that anyone that would run a 24 spline on 900HP is the (word you said above). Here is a good question for you, call MOSER/STRANGE/MARK WILLIAMS/THE GMR and tell them that you are running 900 RWHP in a 3500# sticky tired car, and simply ask what spline would be desirable for axle/carrier spline out of 28/31/33/35/40…….they WILL tell you that 35+ splines would be needed. Now as for the circle track 24 spline, when a 35 spline is offered…..that is a NO brainer! 35 spline is superior and will handle the abuse. How many DRAG floater kits run 24 spline drive plates……..the answer is ZERO! Why do you think? Exactly, they do not hold up.

As for brake size…this is your strongest argument….yes 11-12” rotors could be adequate? But again a lot of the most serious of PRO TOUR cars will not run these as they look small in the larger wheels. So again, another reason these kits are not PRO TOUR. And do you really want to defend a steel rotor adaptor vs. an aluminum one? Wow, sometimes I think people just want to be argumentative. No hard feelings either way

[HarleyR]

Im not saying the 31/24 set up is gospel.. but its a lot more durable than you give credit.. every cup car you see on TV every sunday is running a 31/24 set up... I wouldnt go as far as saying that the failures are regular.. like i said Ive never had an issue with a 31/24 set up... If you feel that strongly about it call Hendrick Motorsports Gibbs and Roush and tell them they all wrong...because you called them all morons... Im not sure if your saying a PT car harder on parts than a cup car or not... I cant imagine a parking lot cone race,weekend track day or a few miles on the power tour destroying parts... in such a regular fashion...not saying it does not happen cause ive seen some pretty crazy stuff... A larger set up would be a great plan and the stuff you pictured looks nice... Im not a fan of Wilwood but you have a solid set up... Where did the picture of the driveplate come from? were the driveplate splines straigh on the axle? on a cambered rear end when they should have crowned axles.. this causes wear rather quickly

[BADDRIDE II]

Im not saying the 31/24 set up is gospel.. but its a lot more durable than you give credit.. every cup car you see on TV every sunday is running a 31/24 set up... I wouldnt go as far as saying that the failures are regular.. like i said Ive never had an issue with a 31/24 set up... If you feel that strongly about it call Hendrick Motorsports Gibbs and Roush and tell them they all wrong...because you called them all morons... Im not sure if your saying a PT car harder on parts than a cup car or not... I cant imagine a parking lot cone race,weekend track day or a few miles on the power tour destroying parts... in such a regular fashion...not saying it does not happen cause ive seen some pretty crazy stuff... A larger set up would be a great plan and the stuff you pictured looks nice... Im not a fan of Wilwood but you have a solid set up... Where did the picture of the driveplate come from? were the driveplate splines straigh on the axle? on a cambered rear end when they should have crowned axles.. this causes wear rather quickly

Sorry, but not feeling like giving credit to a flawed system that should have been replaced years ago. As for calling your respected sources (Hendrick/Gibbs/Roush) , I’m not thinking they are even remotely interested in debating this…but if you would like to arrange, and they accept, I would have NO problem discussing a component for component breakdown of the GMR kit and am sure at the end, they ALL will conclude too, that this GMR kit IS best suited for PT type application over the CIRCLE TRACK offerings. These guys are well respected for a reason and I am sure they would recognize quality when they see it. I doubt they will be as argumentative as their supporters. Good racers, respect good parts.

When one of us “little guys” ever experiences a problem/failure with a part on one of our cars, it is safe to say we remove the part and replace it with something that works (especially when one is offered “over the counter”). I believe it is just old school stubbornness that keeps this weak link around….not to mention the politics of getting all classes to approve and improve. If you/anyone want to SETTLE for this 31/24 setup and risk the LIKELY event you will strip a drive plate/break an axle/hub body…then you can SETTLE for old technology designed for CIRCLE TRACK and ruin your weekend and most likely your car as well.

To compare THE GMR floater kit to any CIRCLE TRACK kit would be like comparing an alligator to a lizard!

Yes I would most definitely say that a serious PRO TOUR car is MUCH more brutal on a set of hubs/drive plates than Roundy Round. A CIRCLE TRACK 24 spline drive plate was NEVER intended for 500-600-700+ HP that would be constantly dumping the clutch and is why these failures occur (now some will want to chime in on the lack of traction argument, but if you know how to set up your car for weekend track days with even just a drag radial you WILL and can hook) with sticky tires….even if it is just now and then that you will visit the straight track or even just dump the clutch for kicks….do you really want to say a prayer each time you get a wild hair….no thanks…I will go with a system designed specifically for BOTH hard cornering, AND clutch dumping impact as well as the added bonus of larger rotors.

The GMR has incorporated the best of CIRCLE TRACK, OFFROAD & DRAG Full Floaters to create one incredible, affordable, application specific kit. To date, the only arguments to my recommendation of The GMR kit, are from supporters of others kits that are designed for CIRCLE TRACK, known to fail, and are cheaper…..are we listening to ourselves people? I rest my case.

[andrewb70]

Let's not hi-jack this thread. Clearly there are different ways to address the hub arrangement.

Andrew

[BADDRIDE II]

Let's not hi-jack this thread. Clearly there are different ways to address the hub arrangement.

Andrew

You are right, I got caught up in the moment!

[funcars]

Experience with cambered rear - 1.5 degree neg on both sides with superspeedway rear hubs, stock car products crowned axles and coated hardened drive plates. I have not had any issues with drive plate wear or axle spline problems. I also have a non-cambered rear same set up that I ran longer and no problems there either. Tire wear isn't as good on a large camber rear. .75 to 1.0 range is probably better for a more street oriented car. I used to have a mainly street V6 Alfa with a .75 cambered rear DeDion solid rear and it did not chew up tires any faster than a flat rear, but it worked noticeably better on the track and was able to use a bigger rear anti-roll bar.

Good luck with your choice

[BADDRIDE II]

Hey funcars, great info on your experience with cambered rears. I am curious as to how much HP/TRQ at rear wheels you ran on this 1.5 degree setup with crowned axle? Is this the steel hub with larger 5" on 5" bolt pattern? Any pictures?

[ace_xp2]

Cambered rear ends can turn that camber into toe in or out depending on how the suspension is designed. Making sure the rear end maintains an acceptable position under pitch and heave becomes more important. Though it seems crowned axles worked well for funcars (is that a street ride funcars?) Cone and winters make ball drive ends (they look like cv joints with a splined center).
Cone even makes one in 35 spline, for those times when you make more than 900hp at the slicks you always use while apparently driving harder than a grand national racer (those guys are basically loafing along out there though). But it's a truck setup so I think the smallest they do is 5x5.5.
http://www.coneindustries.com/partsgallery.php#
Winters Closed Tube Catalog
Warning, the Winters catalog is a 12mb pdf link.

[BADDRIDE II]

Cambered rear ends can turn that camber into toe in or out depending on how the suspension is designed. Making sure the rear end maintains an acceptable position under pitch and heave becomes more important. Though it seems crowned axles worked well for funcars (is that a street ride funcars?) Cone and winters make ball drive ends (they look like cv joints with a splined center).
Cone even makes one in 35 spline, for those times when you make more than 900hp at the slicks you always use while apparently driving harder than a grand national racer (those guys are basically loafing along out there though). But it's a truck setup so I think the smallest they do is 5x5.5.
http://www.coneindustries.com/partsgallery.php#
Winters Closed Tube Catalog
Warning, the Winters catalog is a 12mb pdf link.

I agree ace xp2, suspension has everything to do with how successful or un-successful a cambered rear will be, especially on a street car that is driven regularly. The least amount of pinion angle change from original cambered setting at ride height, the better.

I personally do not think that a cambered rear is desirable for a car that will be driven primarily on the street or long distances, with occasional weekend type track events.

Although the crowned axles are the way to go in a cambered rear,you are at even GREATER risk of shearing/stripping the drive plate and or axle splines since the spline engagement (amount of spline meshing surface ) between the drive plate and axle spline is far less than that of a Zero cambered rear with straight axle/spline. So in my opinion for a PRO TOUR (all around car), a Zero camber rear would be the best choice for strength and all around drivability/longevity due to the GREATLY compromised spline engagement on cambered/crowned rears/axles. As you all know, the 24 spline drive plate is already questionable with even full spline engagement……add a crowned axle with less spline engagement and you are asking for problems.

If you are building a track only type car, than by all means take full advantage of a cambered rear, but be prepared to replace both driveplate and axles approx. every thousand miles like cup cars do, as these parts are generally worn, and or are known to fail soon, and are not worth the risk of failure in future.

So not only would I never run a 24 spline drive plate on a 500+hp PRO TOUR car with manual transmission & sticky tires (at track or street), definitely do not run a crowned axle that is even weaker!

Now as for the CV type drive plate, it is not applicable toa typical PRO TOUR car…..not only is the bolt circle and stud size not applicable……the hub bore on the wheel would be huge…..like a truck….oh that’s right,it is for a truck……….

[andrewb70]

You guys should all check out this build thread:

https://www.pro-touring.com/showthre...bird-%28-74%29

That guy is building a de dion rear suspension set-up. He build the axle and is using a Ford Cobra 8.8" center section. The axle mounts Cobra spindles which can be adjusted for toe and camber. Neat set-up!

Andrew

[BADDRIDE II]

That is a very unique build! I hadnt seen this. Obviously has the issues associated with "cambered" floater rears worked out with that design. And given that he will only experience 1.5+- suspension travel....his camber/toe will remain as set through entire suspension travel. Cool how he can add shims for toe adjustment too. Very talented fabricator!

[ace_xp2]

Glad you're picking up what I'm putting down... Though I should mention that the winters set up is also a ball drive, and not made for a truck B.C.