Making an Automatic C5 Tranny Stronger!
Thread Starter
Intermediate
Joined: Apr 2006
Posts: 47
Likes: 0
Making an Automatic C5 Tranny Stronger!
Hey everyone my brother and I are going to get the STS kit's installed on our vettes. However his Vette is an 01 C5 Automatic, what can he do to strengthen his driveline, he dosen't want to manual so that's not an option. How much would it cost and what would need to be done to handle 550hp reliably as a daily driver? We both do not race or intend to run drag slicks or anything like that, however when the (closed course) is free of other drivers we both do enjoy putting the petal to the floor every now and then. Thanks alot everyone! I'm defiently glad I finally joined these fourms!
Team Owner
Joined: Jul 2003
Posts: 20,474
Likes: 2
From: Detroit
The auto is far better than the manual once you build it properly.
For the stick car I'd do a DTE differential strut brace ($400) and a Lingenfelter or DTE hardened output shaft ($250). Obviously a clutch will pad the bill by another $1,000 at least.
For the auto I'd have it hardened by RPM or FLT. Figure around $2,000.
The turbos will be much more responsive on the auto car. Plus less of a boost drop between gears.
Mark
For the stick car I'd do a DTE differential strut brace ($400) and a Lingenfelter or DTE hardened output shaft ($250). Obviously a clutch will pad the bill by another $1,000 at least.
For the auto I'd have it hardened by RPM or FLT. Figure around $2,000.
The turbos will be much more responsive on the auto car. Plus less of a boost drop between gears.
Mark
Le Mans Master
Joined: Jun 2004
Posts: 7,155
Likes: 154
From: The Arid Sunny Desert
To beef up an A4 look to spend up to $2,500 with installation. You can buy a beefed up tranny for approx $1,600.00, if you can remove and install it you would save the install. It's also a good time to upgrade the torque converter as the labor is free. I can relate as I've just had this done.
Team Owner
Joined: Oct 2001
Posts: 46,766
Likes: 5
From: Boynton Beach Florida
St. Jude Donor '07-'12, '20
Rodney (crashed94) here on the forum builds kick *** transmissions. You might want to consider the A4 in your car as the manual transmission cars are the weak link in Corvette production. This does not mean i'm calling them bad, just letting you know that you will break many more parts than he will. Your brothers car will break far less parts than your car. If you are not wanting to go automatic, I would suggest a call to DTE (here on the forum) for their driveline upgrades. You can thank me later. 
Thread Starter
Intermediate
Joined: Apr 2006
Posts: 47
Likes: 0
Yeah I understand the Corvette Trannys are a little weak but I guess you can't really blame GM for it. Back in 97 I doubt someone at the GM Design Team said "Hey let's beef up the trannys, cause someday people minght be mounting twin turbos behind the back tires!" So I considered the upgrades for my M6. One question tho. How long would a stock A4 last with around 67k and just the STS kit?
Update: Visited RPM and...
All of our LEVEL IV automatic transmissions include:
RPM sleeved input drum
RPM 3-4 clutch pack
RPM sunshell with laser welded collar and bearing
Heavy Duty double caged 29 element sprag
4L65 low roller clutch
Transgo HD-2 shift kit
Corvette Servo
Wide 2-4 band
Updated aluminum accumulator piston
Bushing kit
new shift solenoids
new GM valve body spacer plate
Seal & gasket kit
Filter
Set end play to our specifications
For $1595+129 shipping of the tranny to me and core to them!
Would this be enought? Also how long would a 67k stock a4 last?
Update: Visited RPM and...
All of our LEVEL IV automatic transmissions include:
RPM sleeved input drum
RPM 3-4 clutch pack
RPM sunshell with laser welded collar and bearing
Heavy Duty double caged 29 element sprag
4L65 low roller clutch
Transgo HD-2 shift kit
Corvette Servo
Wide 2-4 band
Updated aluminum accumulator piston
Bushing kit
new shift solenoids
new GM valve body spacer plate
Seal & gasket kit
Filter
Set end play to our specifications
For $1595+129 shipping of the tranny to me and core to them!
Would this be enought? Also how long would a 67k stock a4 last?
Last edited by VetteC501; Apr 19, 2006 at 04:19 PM.
Team Owner
Joined: Jul 2003
Posts: 20,474
Likes: 2
From: Detroit
Really depends how much boost your running and what tire you run. Although some have gotten away with boost on a stock A4 with a good trans cooler, I wouldn't hold your breath.
At 500 rwhp my M6 was fine even with the stock clutch. The stock clutch didn't last long at all with drag radials - nor did the trans.
Mark
At 500 rwhp my M6 was fine even with the stock clutch. The stock clutch didn't last long at all with drag radials - nor did the trans.
Mark
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Riiiiight. That's what I thought 5 lbs ago. 
