Looking for Rear Diff Advice - SS, Auto, FI

[ostmike]

We decided to invest in the Gen5 Camaro platform and purchased a 2011 Camaro SS with a Whipple. We do have a tough time keeping things stock or mildly modified but for now we want to see what we can do with this config before going large frame turbo.

I have searched the forums and can't seem to come up with a definitive answer to this question:
What mods should we make to the stock rear diff to hold the most power? We will most likely be swapping to a 17" rear wheel and MT "R" for more sidewall and softer impact.

I know it's a loaded question but right now, on our dyno with a few hours of tuning the car is making 550whp at 9-10psi. Cars with this power to weight ratio (on our dyno) generally run high 10's and 60' around 1.6x

For reference, on our dyno a stock 6.2 makes about 350whp.

We will be going with a smaller upper and larger lower pulley so we assume we will be bumping the boost to roughly 14psi. We are not sure what that will yield power wise but would like the rear to last as long as possible. We will only be tracking the car once or twice a month.

Suggestions? Best vendor for diff mods? LPW support cover? Cap kit? We are a DSS dealer so we will most likely go with their axles and DS - unless someone can recommend otherwise.

Thanks in advance!
Mike

[cc-rider]

The best options for the STOCK diff is the Eaton TruTrac locker, and maybe add a LPW diff cover as well. People have done reasonably well with this. This is about $750ish in parts. Labor is additional unless you can do yourself.

Your best option in general is to upgrade to a ZL1 diff. You can do this for ~$2k used. Or $3800 new.

[ostmike]

Anybody have input/experience with this item:
http://www.camaro5.com/forums/showthread.php?t=474107

[ostmike]

Originally Posted by cc-rider

The best options for the STOCK diff is the Eaton TruTrac locker, and maybe add a LPW diff cover as well. People have done reasonably well with this. This is about $750ish in parts. Labor is additional unless you can do yourself.

Your best option in general is to upgrade to a ZL1 diff. You can do this for ~$2k used. Or $3800 new.

Thanks for the reply! What does your car 60' and ET? MPH?
Just trying to get a feel for what to expect with this platform.

[cc-rider]

Originally Posted by ostmike

Thanks for the reply! What does your car 60' and ET? MPH?
Just trying to get a feel for what to expect with this platform.

I haven't run yet except for on stock tires. Just got the ZL1 diff installed and bought some drag radials so I'll know more next summer. A guy with username dreksnot here on this site has done a lot of dragging with the ZL1 diff (multiple of them) and could give you a lot of info.

[dreksnot]

Just to set things straight from the beginning - I race like a monkey and a football... (where's the emoticon?)

M/T ET S/S 305/40R18 tires and 2-step (4,700rpm) launch I get 1.6x 60's. I just switched from Nitto NT05R's so I'm relearning tire "running parameters." Once I get them figured out I'm guessing high 1.5's low 1.6's 60's. 10.8sec@128mph up in the stratosphere DA of 7,724ft

ZL1 differential is a heavy bitch, about double of the stock diff, but it's about that much stronger too. It's taken some pretty violent starts.

[ostmike]

Originally Posted by dreksnot

Just to set things straight from the beginning - I race like a monkey and a football... (where's the emoticon?)

M/T ET S/S 305/40R18 tires and 2-step (4,700rpm) launch I get 1.6x 60's. I just switched from Nitto NT05R's so I'm relearning tire "running parameters." Once I get them figured out I'm guessing high 1.5's low 1.6's 60's. 10.8sec@128mph up in the stratosphere DA of 7,724ft

ZL1 differential is a heavy bitch, about double of the stock diff, but it's about that much stronger too. It's taken some pretty violent starts.

Good info. Manual trans cars are definitely hard on the rear diff.
I would recommend going to a MT Street "R" over the NT05's

If this was a manual I wouldn't even try to run the stock diff. If we can't make this stock diff with mods last the ZL1 looks like the next option.

Thanks for the feedback.

[cc-rider]

I have a buddy who ran his stock auto diff on his Magnusson blown car for many many passes. I can text him and see if he'll come on here and respond with his 60' times. The stock diff seems to hold up on the auto cars fairly well....

[ostmike]

Originally Posted by cc-rider

I have a buddy who ran his stock auto diff on his Magnusson blown car for many many passes. I can text him and see if he'll come on here and respond with his 60' times. The stock diff seems to hold up on the auto cars fairly well....

Thanks.
I guess what I am really looking for is tips on making the stock diff last while cutting 1.5 60's (or maybe 1.4x) with this heavy car. I see a few folks posting that they have. I would rather learn what they did and avoid the mistakes

[pancherj]

http://www.camaro5.com/forums/showth...highlight=rear

Talk to Mr. Nasty...he can steer you in the right direction. The auto will really help to cushion the rear and axles.

[cc-rider]

Originally Posted by ostmike

Thanks.
I guess what I am really looking for is tips on making the stock diff last while cutting 1.5 60's (or maybe 1.4x) with this heavy car. I see a few folks posting that they have. I would rather learn what they did and avoid the mistakes

I just talked to my bud. He was running consistent 1.59-1.61 60' times with his car. Launching from idle was always his best result he says. His best time was 11.02 I think. I know it was right at the bottom end of the 11's because he was knocking on the door of 10's very very close.

But that car took many many passes. In fact the guy he sold it to still drags it. Still holding up well.

[frankwjr]

ZL1 fer iron clad but IMHO missin major factor...ur clutch....regardless rear setup stocker isn't goin to last long so has to be a consideration...wat is ur current setup(still stock?)and any plans?

[Mr. Nasty]

Just run it. I have beat the hell out of mine for 5 plus years. This car is at the track year round. I have ran 17" and 18" DR slicks cutting mid 1.40 60' to low 1.50s 60'. Other then some suspension work the diff and axles all stock with 3.91 gears.

[ostmike]

Originally Posted by pancherj

http://www.camaro5.com/forums/showth...highlight=rear


Talk to Mr. Nasty...he can steer you in the right direction. The auto will really help to cushion the rear and axles.

Just the kind of info we are looking for. Thanks! Any more threads like this with details on stock rear diff mods? Maybe I should have posted this in the "Dragstrip and Launch" forum?

Originally Posted by Mr. Nasty

Just run it. I have beat the hell out of mine for 5 plus years. This car is at the track year round. I have ran 17" and 18" DR slicks cutting mid 1.40 60' to low 1.50s 60'. Other then some suspension work the diff and axles all stock with 3.91 gears.

Huh! I like your attitude We will be putting aftermarket axles in it. Just trying to understand the limits of the stock diff and options to strengthen it.

Thanks!