mello-yello
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Heel & Toe
Joined: May 2012
Posts: 17
Likes: 0
mello-yello
Hello from a new C5 owner! I've determined this automatic equiped car has 3.15 rear gears, and I'm thinking of upgrading to something in the 3.30 to 3.50 range, for more low-end grunt & acceleration. The work is beyond my expertise but I'm looking for any tips on what has worked well for others. Not looking to build a super-street car, the engine will remain mostly stock, only some minor upgrades. I've heard a stall converter is good to pair with the gears, but necessary? And what negative impacts to the converter, if any like decreased fuel mileage?
Any special areas I need to discuss with a shop when I contact them? I'm in northeast Pennsylvania and this area doesn't have a lot of speed shops so any recommendations on a shop in a 75 mile radius of Wilkes-Barre are also appreciated!
Thank you one & all for any advice you can offer!
Any special areas I need to discuss with a shop when I contact them? I'm in northeast Pennsylvania and this area doesn't have a lot of speed shops so any recommendations on a shop in a 75 mile radius of Wilkes-Barre are also appreciated!
Thank you one & all for any advice you can offer!
Pro
Joined: Feb 2011
Posts: 565
Likes: 0
From: Broussard Louisiana
Your not going to see much difference with the 3.30 or even with the 3.50 really from the 3.15, I wouldnt even change it I would spend the money on something else like a fast intake,Headers,and throttle body. Or maybe a cam. 3.15 is a good ratio for street and doesnt kill your wallet on fuel mileage
Safety Car
Joined: Apr 2007
Posts: 3,582
Likes: 137
From: SoCal CA
It would be easier and maybe even cheaper to just swap to a C5Z06 rear. They come with 3.42 gears which are a nice combo of low to mid acceleration without losing much top end acceleration. Youll feel a difference between 3.15 and 3.42. As for a converter, it all depends on whether youll upgrade the cam in the future. A torque converter should be paired with the right cam for the best performance. On a stock motor Ive seen guys happy with 2400rpm stalls or in that area. Your mpg will stay basically the same. If they get worse its from you enjoying the car. Lol. Youll get better acceleration and it will be more efficient allowing more power to get to the wheel, lees of a parasitic loss in other words.
Drifting
Joined: Mar 2011
Posts: 1,412
Likes: 15
From: Richardson TX
All C5s with manual transmissions have 3.42 rear ends. If you look around on craigslist, ebay, or this forum's for sale section, they're easy to find for $400-500. Z06 differentials are stronger, and more expensive. If you don't have much more power than stock, there isn't much of a need to install a Z06 diff IMO.
Expect a shop to charge around $450 to swap out the differentials. That should also include putting fresh gear oil in it.
The earlier C5s had "single rib" differentials, and later years (I think 01-04) used "3 rib" differentials, which have stronger cases. The single and 3 rib is describing how many braces they have on the top of the case.
Expect a shop to charge around $450 to swap out the differentials. That should also include putting fresh gear oil in it.
The earlier C5s had "single rib" differentials, and later years (I think 01-04) used "3 rib" differentials, which have stronger cases. The single and 3 rib is describing how many braces they have on the top of the case.
Drifting
Joined: Mar 2011
Posts: 1,412
Likes: 15
From: Richardson TX
The C5 Z06 differential is no different than the 2001 -2004, 3.42 (manual trans) differential. As mentioned the pre 2001 cars came with single rib cases and that case is a bit less strong as a result.
OP any 3 rib 3.42 ratio differential you get will work fine as will the single rib case from the earlier manual trans cars if you have stock HP.
OP any 3 rib 3.42 ratio differential you get will work fine as will the single rib case from the earlier manual trans cars if you have stock HP.
