delete

 

It will not blow. Take it easy on the launches and change the fluid regularly. Many, like myself, are running the 6 speed on higher horsepower builds than yours and it is just fine.

I am over 450hp / 400 torque by the way.

Launches and really hard shifting is what will kill it. It is known for overheating and input shaft problems, if you are taking it auto crossing consider throwing a transmission oil cooler on to up the capacity and keep it cool.

Good luck

 

any other input?

 

i shattered just about everything in my 6 speed after overheating it with about 375hp/360tq

have since had it rebuilt once - incorrectly - by some shop here in tampa
and rebuilt it again myself

The six speed is very susceptible to overheating due to the smaller fluid capacity and the smaller surface area of the gears. If you can, add a transmission cooler with a tilton oil pump. If the transmission does fail, cryo treat your syncros, polish the sleeves, and shot peen all the gears. After that it will be pretty much bulletproof.

Also as per recommendation from Jon@TRE, never use a clutch designed for holding more than 400tq.. it will kill the already super fragile syncros

 

4th, 5th, and 6th gears are all skinnier than the standard 5 speed tranny

tracks that you'll find yourself utilizing 4th gear for extended periods of time will be the death of your tranny

heat kills them and high torque numbers kill mr trannys

a member warrtalon had dragged and autocrossed is car over 200+ times at 350wtq...his mr tranny never failed until he started tracking it at higher speed tracks

he beat on his car more than most members ever will

 

what torque numbers are like max safetly on a mr trans

 

The transmission is rated at 290tq from the factory.. that number is really useless though

The strength of the transmission really depends on your driving, your clutch, and your tq levels..
I took my car to the drag strip 2x per week for about a year and I had ZERO issues with it at 360tq until i started hotlapping it -_-

HEAT IS WHAT KILLS THESE TRANSMISSIONS

 

my Ix mr have 342 whp and 340 whp ,what clucht recomended me? 6 speed

 

^^

Get a Exedy Twin Disc and be down with it.

 

Im going to run my quatermaster twin disk till I blow it blows up then im going to do a built 5spd and get the 5spd rebuild kit to use it on the new trans.

 

and what clucht do you use ???

 

It will not blow with 300-400 hp, it does take a lot too break it. Some guy just over do it saying that its weak but its really not. All you have to do is the proper maintenance like any other tranny and you will be fine. I used BG synchro shift on my tranny and it worked fine. With the number you are looking at getting to you will have no problem. Just get a good clutch to get the most out of the power you will be putting down.

 

If you know how to drive your car and don't rag it you'll be fine. I've had no problems with my transmission with 420hp and 65k miles.

 

I'm at 505awhp and 460lbs of torque, no problem. My cousin had an MR, put 40k miles on it, street and track without any issues.

 

thank you those most recent posts help me out the most, ivey tuning told me that the mr trans can hold up to 450 pretty safetly so im not worried anymore. i am actually gonna put it on the road now so i can take it to the dealer to have it checked out since its still under warrenty and nothings installed yet