Nissan 370Z Forum - Forced Induction gains and 7AT

Nissan 370Z Forum (http://www.the370z.com/)

- Forced Induction (http://www.the370z.com/forced-induction/)

- - Forced Induction gains and 7AT (http://www.the370z.com/forced-induction/9468-forced-induction-gains-7at.html)

Quote:

Originally Posted by One_Quick_Z (Post 235462)

I would think the 7AT could handle 450whp easily, But thats just me

DAN

Well, the difference between think and uh-oh is only about 15K...assuming a new transmission and a FI system that you can't use without blowing another tranny ;)

Im going based off of the old tranny and its power handling capabilities, also this is the trans out of the FX50 is it not?

DAN

Quote:

Originally Posted by Lug (Post 211042)

The 350Z's AT was only good to about 400 to 420 RWH before mods were needed. I'd hope that the new 7AT handles more power. Another problem with the 350 AT was that when you went FI, the slower shift speed of the tranny would allow the RPMs to jump and hit the rev limiter when shifting under full acceleration. The fix was a throttle body upgrade on the tranny and/or a software change to the rev limiter level.

Quote:

Originally Posted by Lug (Post 212500)

Hopfully so. From what I've read, the full shift time has dropped about 500 milliseconds between the two trannys. That's an incredible improvement. I think the same 7AT is used in the FX45 (390 HP stock). If so, I'd imagine it's power handling has gone though the roof as well.

I am going to mostly agree with Lug I would bet that the trans can handle somewhere between 420-430 HP. Now the real question is how much torque can it handle. reason I say this is because most trans are rated by how much torque they can handle, the Z's don't put out an incredible amount of torque stock but adding F.I. will drastically increase the torque that the drive train has to handle therefore adding much more stress.

We can speculate all we want but until we start seeing high hp/tq or F.I. cars dropping trans and looking at what numbers they are killing them will we truly know the answer. Add to that driving style will have a lot to do with how well the drive train handles the power as well. if you are a street light racer every light and push your car regularly you may see a failure at a lower hp/tq level than someone who is a less aggressive driver.

So really who knows do some research as Lug has and we can add lets say 20-30% over engineering to what they are handling stock and that is probably a safe number to stay around for starters at least.

the factory engine torque is 270lbft but the rear wheel torque (as was measured by the fx50 dyno or a 370z dyno) would be less in a Z ~230 ish.... remember a stock engine torque rating for the fx50 is 369lbft.... or about 100lbft more at the engine then a Z.... Even if this translates to only 70lbft at rear wheels (as evident by the dyno) that is a substantial built in margin. Thats why I posted an actual dyno sheet of the rw torque rather then the official values, but even so the engineerd cussion would be above the fx50's value...380-390lbft at the engine would be a very conservative guess ie about 320rwtq... ok last post for a very long time.

EDIT: Interestingly that Greddy turbo kit looked to be about 330-340rwtq at about 450rwhp and 6.4psi.... so just dial back to 4.5 to 5 psi and you theoreticly should have a 400rwhp/310rwtq car. Still would be very very quick at 3200-3300lbs.