That's worrying, guess the trans in these cars or more specifically the valve body and tc cant take more power

I've done a lot of research on this transmission, it's also used in several other sports cars, the miata newsgroups were very helpful. I just re-read this whole thread. NOT ONE WORD ABOUT FLUID TEMPS! If you're using the stock cooler with FI, you're probably getting symptoms because the transmission got cooked. The stock intercooler is only good for street use. It doesn't have the capacity for track use. It can't even handle stop-and-go traffic without going above 200 degrees. The people who say this transmission can handle 450 HP are absolutely correct. They install an auxiliary transmission oil cooler first, to handle the extra heat. If you want to boost your AT car, install an auxiliary cooler first.

Ok sure but riddle me this batman; from everything I understand operating temp for the AT is 200 degrees. When when NA I've experienced shifting problems when this transmission is "cool".

http://www.ft86club.com/forums/showthread.php?t=78266

http://www.ft86club.com/forums/showthread.php?t=61498

I'm about to spend a crap load of money at SSP but the one thing I'm not really thinking about at the moment is the transmission cooler because I live in a cold climate and drive the car year around. There's no hope of that tranny getting to operating temp with a cooler in the winter time.

I'll speak to Kris at SSP and get his opinion; what's another $1000... :cry:

You can get something like an hks sandwhich plate or another similar product that will not flow oil to the cooler at lower temps. Or you can go another route and just put cardboard on the cooler when it gets cold. I suggest something like the first option 😛


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Thanks dude for being the Ginny PIG. :) Just out of curiosity how much is, just the tranny rebuild going to cost you ? because if this works for you without adding the transcooler than we will definitely want to follow that route too, the only reason we cant go that route here directly is because we are short on any suppliers for aftermarket parts for the gt86 and if we were too import it the Rand to dollar exchange very bad and would cost us a fortune.

Transmission fluid is heated by friction, not ambient temperature. You could overheat this transmission in Alaska. As far as being too cold, you couldn't be more wrong. The existing heat exchanger is left in place, just plumbed in downstream of the new cooler. A thermostat on the new cooler can redirect the fluid back until it is up to temp, and even without a thermostat, the engine coolant brings the temperature back up, no matter how cold it is outside. Synthetic ATF should shift the same hot or cold, since the viscosity doesn't change with the temperature. The thing to worry about is the plastic or rubber components of the transmission melting/deforming at temperatures above 200 degrees F. Melted plastic/deformed rubber cannot be undone by a fluid change.

Any more info on the trans upgrades or possible resolution to the shifting issues at higher boost/HP levels? Recently boosted my FRS, Ecutek tuned @ 11psi on E85, 350hp with a tranny cooler. On track yesterday (first time boosted at the track), regardless if hot or cold, the car would shift great from 1st-4th but the shift to 5th was always very slow (similar to the video) and the car would throw a couple of different codes; P2757 (TCC (torque converter clutch) isn't locking ) during 2 sessions, which was reset each time and P0700 (trans slip) during my last session. Codes were thrown independently. It's possible that the P2757 codes were due to TCS activity while trying to shift, I was learning how to drive at this power level and manage tires; cooked them in the first couple sessions, which is when I saw P2757. Next 2 sessions I took it easy (7 or 8/10ths) and didn't didn't throw any codes, never shifting out of 4th. Last session I pushed a bit harder, shifting into 5th down the back stretch at Road Atlanta. This last session was when the P0700 was thrown. If I had the GoPro mounted to the helmet, I could better diagnose when the codes showed up and under what conditions, unfortunately, it was mounted on the splitter.

What transmission fluid are you running? I changed/flushed my fluid with Amsoil full synthetic ATF. What were you doing about the traction control? Did you do the pedal dance, or did you pull the fuse? The ECU might be refusing to lockup the converter to prevent loss of traction. The transmission TCU might also be acting up because of fluid temp. Any time the converter refuses to lock up, it generates excessive heat, too much to be removed by the OEM intercooler. This is the reason for an additional transmission fluid cooler upstream of the OEM cooler. It's a good thing you're running an additional cooler. An additional temp sensor could easily be plumbed into the additional cooler to give a readout of the fluid temperature, then you could see if the TCU starts acting up above a certain temp.

Using Toyota WS, which was drained and filled after the cooler was installed and filled with fluid. Since this was my first track day FI, I left TC on for the first couple sessions and put it in Sport after that, not experienced enough to turn it off completely yet, especially not at Road Atlanta. Took it to the mountains yesterday to give it a good workout and see if I could recreate the codes, but no codes were thrown (ran with E85 and 93). I've considered adding a temp sensor in the trans line; adding oil temp/pressure this week, as well as boost, so an ideal time to do it. Spoke with Kris at SSP today and apparently the stock clutch is good to 400HP and the reason for the lag in shifting is due to lack of pressure from the valve body.

This is so odd to me, I've never seen this either but reading it makes me wonder, I have a MAP Turbo kit on my car and I am pushing over 350tq on the AT and on full throttle I never hit this problem. Makes me really wonder what you've got going on. I have the SSP Trans cooler and it helps so much.

For everyone following along, Kris said my transmission will be ready the week of the 20th. Updates to follow...

Also, who else here is boosted with the Auto? What's your throttle response with a turbo in 1st gear. Mine is horrible until the turbo gets spun up

I can definitely see how pressure would cause a shift lag. I often let off the throttle when I shift, to get it into the next gear faster. Different fluids will also affect pressure. I'd like to see a shifting fix marketed, that only replaces one simple pressure-regulating spring, and is easy to remove and install. Oh, and cheap too!

I asked Kris at SSP about this and he had the following to say...

Did you ask him if there is a simple fix for the pressure problem?