Hello guys, my ISF was wrecked and im lookin for a new project and wanted a coupe that would make as much power as my ISF, so im looking at 08s/09s.

So the 09 has the 7AT and 08 has 5AT correct? Which one would be better if i was going to install a TT kit?

 

You're going to need to upgrade your transmission in either case, personal preference, but probably 7at, since it has fewer issues.

 

Im not so sure about that. What other cars is the 7speed used in? I dont know the model number of the 7AT.

The 5AT (Jatco RE5R05A) is used in a bunch of models including the Nissan Titan which puts out close to 400ft lb of torque. The extra torque from the turbos is what will kill the trannie and the 5AT is proven up to almost 400ft lb....

 

370z has the 7at, also.

 

M56 also has 7at.

 

the is f my dream.

 

thanks for the response guys, i understand other cars have the 7AT im just wondering which tranny is better for turbo application and which one would shift better with a twin turbo kit.



yeah i miss her...

 

Just build the 7AT as you see fit and welcome to the good side of import sports/luxury.

 

7at has such short gearing in the first 3 gears that I would think the 5at to be better for turbo applications. Not sure if either is good for longevity with forced induction. Upgraded valve body and upgraded clutch packs would be a good idea. How much power you looking to run?

 

Why are you looking at the AT's for a project car anyway? The 6MT is the far better option. Upgrade the clutch and away you go.

 

the new rc f

 

Exactly!

Both the 5 and 7 AT will need to be rebuilt if they are to be abused and I'm not just talking valve body upgrades and UpRev tunes.

 

You can use any transmission really. They all work if you dont beat on them.

The 5at is a stronger tranny though. The 7at has many issues when it comes to FI kits

I would highly suggest doing some upgrades and forgo the valvebody upgrade. I have done a lot a research and found that the valvebody is pretty much useless! It is cheaper to build your transmission with clutchpacks, gaskets, etc then it would be to do a valvebody and it will hold up waaaaaaaay better. I first got a gtm valvebody and it was found to be one of the main factors that destroyed my old transmission. I will never go that route again.

So in conclusion get a 5at and take it to a reparable tranny shop to get parts upgraded. It will be a much better option.

 

thats waht i was thinking. im trying to run around 500hp

its not a project car, itll be a daily driver plus sometimes i take the suv around so my gf and mom need a car to drive

i know a rebuild is needed just debating between 5/7

i dont plan on dragging or tracking the car...just a daily driver with some power behind it. but this post was very helpful, thanks alot sir

 

Alkatraz is correct. 400ft lbs of tq is what a stock 5AT with valve body upgrade can handle. My 5AT with upgraded valve body and clutches should be able to handle 500wtq. So far everything has been running smoothly. GTM is the only company I know of that can upgrade the 7AT. Stock for stock, I feel the 7AT is superior, but when adding boost that's another story. In regards to manual vs auto for this platform, it will be less expensive when going FI and there's more FI options for manual. I don't plan on going above 480 wheel horsepower, so the 5AT is good enough for my fast daily driver needs.