Are you running an undertray or ducting air from the bumper to the heat sinks on the transmission? The stock undertray helps duct air to the transmission. Otherwise, you can duct air from the front bumper. The transmissions heat sinks are not nearly as effective at dissipating heat just through convection as compared to air flowing over them.

Personally, I am going to:

• Relocate ACD to rear of car
• install this on the driver side bumper duct
• Run one side to brakes, run the other to the transmission heat sinks.

 

Not that you mention it.. I don't. It could be the reason it overheated like that

 

I ran the stock undertray and it still died. I was doing 30min sessions (until my tires overheated) with 3 to 5 sessions per trackday and approximately 15 track days a year. Razorlab blew 2 of them, one rebuilt by TRE in approximately 2009, there is a thread on evom somewhere that he posted. I was below 350wtq and razorlab was stock turbo with e85 (350ish wtq maybe) as well.

Then theres an evoIX MR on here that was sponsored by a shop and ran 10 seconds with a hta35r and 500+hp over and over in 2010. I forgot who it was since its been so long but again I'm sure that thread is somewhere on here still. That car was strictly daily driven with a few passes down the strip every now and then. Seemed to be just fine.

Theres a lot of trans oil voodoo everybody talks about with the 6spd. Some swear by amsoil, some redline, some GM syncromesh, some a cocktail, and some are strictly OEM diaqueen. For what its worth I was running motul gear300 75w90. I would recommend a friend to run OEM diaqueen only.

At the end of the day enjoy the 6spd for what it is. A great daily driver, maybe a few drag passes a year with an easy clutch, maybe avoid road courses, and keep the tq to whatever you would with a stockblock. If it still blows up you can swap in a 5spd at the end of the day and still enjoy everything else that makes a MR nice.

 

With the 6 speed it all depends on what kind of person is driving. This is just what I see with them

 

I make 360 wtq. No issues on the 6 speed.
You just have to understand you're limits.
Take care of it and it'll take care of you. But I would say the limit would be 400-450 wtq

 

Good point about the heat - anyone have any recommendations for a cooler?

 

It definitely depends on how its driven. I've at 400-425 ft-lbs for about 1.5 years with no issue but I only do 2-4 rips.

 

Raver Motorsports is currently building me a cooler kit. Includes a reservoir to make sure you can keep track of your fluid, temp sensor fitting to make sure the fluid isn't overheating, in-line filter to remove any particles that might be in the circulating, fluid pump, and a cooler. PM me if you guys need a price or help.. I'll have pictures of my setup posted shortly after I receive my trans back from Shep.

 

By the way, the 6-spd I have now was run in a 550whp car that frequented the strip. The car was running a GT35r sized turbo, trans had no issues. After taking everything apart it was clear as day that the reason the trans ran into the issue that it did was due to heat and not power. As long as you watch the temps, use the proper fluid (I was using MT90) and you don't shift like an idiot.. I think the 6 can be made to be just as reliable as a 5 for torque levels below 400.

 

There is a thread somewhere - it may have been on the Motorsport forum - that described a cooler set-up with pump with part #'s etc .to address the issue.

 

Its hit or miss with these transmissions. Obviously there are more trans that break than not. Some people just get lucky I guess, or they regularly keep their fluids fresh. I know guys who have 400whp/350tq who have auto crossed/drag raced their evo's the past 5 years and have not had a problem.

 

Pictures of pump and cooler installation here ... look like a great set-up

https://www.evolutionm.net/forums/mo...ml#post5069714

 

Sub'd for info. I have a 6spd MR as well. I'm still stock and still have the factory under belly installed so I'm not too worried about heat just yet but it's still a concern.

A full oil cooler system would be great but I'm wondering, would air ducts directed at the transmission be an effective way of keeping temps down? I feel the only effective way is having a pump and heat exchanger set up but the cost is putting me off.

 

$500 spent on a cooler setup for the trans could save you $1,500 later on... ask me how I know.

 

Plus, they knew heat would be an issue. The 6 speed has cooling fins built into the case. The 5 speed does not.