BossRos

Hey guys, I got an 04 is300. Planning on starting to build her once I'm off Deployment. Not doing anything too crazy, just looking to make 350 - 400 hp. I know the blocks can handle that, already plan on internals being upgraded. My only concern is the trans. I've heard the stock 5spd trannys arent good for anything past 300 hp or so. I've been researching and haven't come up with much yet. Anybody know of any good manual trans I could swap it with that bolt up with hopefully no adapters? Thanks in advance!

Lexyaaaas

iTrader: (2)

Heres some options, not sure about driveshafts (some would have to be custom)
-w58 or r154 for maybe $2000.
-ar5 (uses r154 bell housing) maybe $2000
-cd009 around $3000-$5000 depending on adapter kit
-v160/v161 at least $6000


Besides that you really need some engine management. Stock ecu cant do what you need

daddystop

Transmissions and clutches don't break because of horsepower, they break because of torque. I always am bugged out by people saying a trans can handle x amount of HP or a clutch holds x amount of HP.

TrueGS300

These guys have a process for strengthening the auto trans. Supposed to handle 500hp. http://is-elite.com/category/is300/page/2/

I am using an Apexi AFC Neo for my NA-T build. I've read some guys have made around 800hp with them in Supras and SC's etc. Should be capable of what you need.

daddystop

http://powerdynamix.com/ - this guy knows how to build the best auto transmissions for A650E cars IMO.

850is300

yes the a650e can handle up to 650hp and around 300 ft lbs of torque with shims under the valve body and bumping the pressure up there are how 2's on this. The only down fall is it shifts hard as hell and you have to run a external cooler cause she will run hot.

2JZSKI

it would be wise to deck and port your engine too, you can't just slap new pistons, rods, and bearings in there. A local machine shop could do everything for you including measurements and install. Researching my own build atm too. Also the T-56 is a good option if you have the $. Lots of after market support and its upgradable.