daleong

What is the designed horsepower / torque rating of the Tremec 7-spd manual transmission in the C7 Z51?

Wondering how much engine performance mods can be made without putting the driveline at risk...

Thanks.

yonks8365

I think it will be more a issue of what the clutch can hold without slipping or burning up. Plenty of guys running over 700hp with stock trans and clutch. But going over 700 more people start upgrading the clutch.

CPhelps

According to the GM Powertrain site, the Tremec TR6070 7 Speed manual in the C7 Z51 (MEP for base, MEL for Z51) is officially rated to 450 lb*ft.
http://www.gmpowertrain.com/VehicleE...nProducts.aspx

Follow the link and select "transmissions" from the drop down. Then select the Tremec TR6070 MEL from that drop down, and click the "Specs" column.

schpenxel

Something tells me they'll handle a little more than that

Higgs Boson

stock clutch and trans here with 9xx rwhp

I'll let you know when it slips.

daleong

Wow, there must be some serious safety or reliability factor that Tremec engineers built into the gearbox.. rated for 450lb-ft but obviously capable of handling a lot lot more (at least for a shortened lifespan?)

Higgs Boson

well, yeah, it's the same thing for every part of your car. they aren't going to warranty the drivetrain for 60K or 100K miles if they were crappy pieces. the more power you add, the faster they will wear out (or just break entirely).

besides, it's not like if you have 1000 HP you are driving around at 1000 all the time. 90% of my driving is probably right around 150 HP, lol. 1000 comes in spurts when the conditions are perfect....it's wednesday, there's nothing good on TV....conditions are perfect. It's business time!

ffr1352

It appears the 7 speed manual in the Z06 is also rated for 450 ft-lb torque so i would have to guess they are way under rated.

daleong

Wow Higgs, you must have a supremely talented right foot!!

Higgs Boson

just a lot of data logging.

JerryU

In another thread someone asked about the manual trans gear ratio differences in a Z51 C7 vs a Z06.
While searching for info I found this thread and the following info in a flyer by Tremic about the TR-6070 trans.

There are 3 versions.

Version A has a first gear ratio of 2.97:1 (the ratio in the Z51) and is listed as capable of handling 460 ft-lbs of torque, which is what the LT-1 engine has.

Version C the most robust, is listed as having a first gear ratio of 2.29:1 and is capable of handling 635 ft-lbs of torque. The Z06, LT-4 has 650 ft-lbs and uses that 1st gear ratio.

No doubt there is a built in safety factor but those adding turbo's etc to their LT1 are probably well past the safety factor in 1st gear. Since 1st gear has the most torque multiplication it is usually the one with the highest stress. The only saving grace is the tires will break loose before all that torque can get to the ground in 1st gear!

I recall when I stuffed a 51 Olds, bored an 1/8 inch for '55 pistons, in my '41 Ford Opera Coupe it blew first gear soon after the install! However with the skinny tires we had in 1960 it would lay rubber (with one wheel, no positraction) in 2nd and 3rd until I lifted! The car was sold with a V60 flathead and a 4:11 rear. It was considered a business man's car.

goec2468

That is correct, depending on the gear ratio, different torque ratings apply.
In the same spec sheet TREMEC wrotes the maximum gross vehicle weight to be 5291 lbs.
Accelerating a 5291 lbs vehicle with a 460 lb-ft engine in first gear will put much more stress on the transmission than accelerating the Corvette.
Therefore the transmission should survive much higher torque values - in a Corvette.
In a Trailblazer it would be a different story ....

robert miller

On a other note here. It has to be in the slower 60 ft times no way would a c5 r c6 stock clutch hold up but every few times at your level of rwhp.

Higgs Boson

now I have an A8 with about 750. never found the limit of the stick.

Wadoka

Back in college, we were introduced to "factor of safety" in design, and engineers being a conservative bunch, we were told to design for double the expected mission, as mechanical engineers. If possible. The civil engineers were told to use 4x as their F/S.