Thread: trans surging and trans temp issues.

im looking for some help here, i have a turbo car with a built trans (3.52 GMR chain and gears) running a 2700 stall converter from cartuning. i have a external trans cooler and i am still using the factory cooler as well. i am seeing temps up to 220 degree street driving and cant keep it cool. for all you turbo car guys what is your setup to keep the trans cool and what stall and gearing are you using?

second issue is once i am in 4th gear cruising the converter locks up as it should and stays locked from barely any throttle to about 10% throttle. once i hit 10% throttle it starts surging (converter lockup and unlock) until around 20% throttle and then after 20% throttle it will stay locked up until i sink into the throttle hard enough to unlock for power. why am i having this surge issue?

i have no idea but you're profile picture is awesome. i hate that show.

John.. that sounds to me like the gear ratio is not 100% correct in the programming. I'm saying this from experience. I'd be speaking to Dave for any insight on how to do it properly.

That was a 3500 stall.

You asked a question, I'm merely trying to help based on the worlds pickiest, most finicky Bonneville in history. That car earned the name Black and *****y from Pman

I'm would have also said incorrect gear ratio. I see the post about high trans temps after gear ratio chance pop up ever 6 months or so on the forum. Other than that, did you flush both aftermarket cooler and cooler in the radiator before installation? Depending on what type of trans failure you had earlier there could be a ton of junk that was put through those coolers.

Edit: About the surging I had a similar issue after I installed my trans but after about 100 miles the pcm had enough time to go through the re-learning process and went away. I emailed Dave about it and said that if it wasn't gone in 2 day of stop and go driving to give him a call....went away before 2 days.

Gears are set in HPT to be a 3.52 Ratio with the correct tire size. I had a thought this morning, trying to play around with the TCC Release speed. Im thinking that it might be too close to the apply and its getting unhappy

P... could be.. However he's using a 3.29 diff, with I forget gear tooth count on the gears.

What I'm getting at is.. if you have 3.29 diff and 1:1 ratio gears, you start with a stock 2.93 file (which says 3.29) and you change it to 3.69, toss in teh tires and hit auto.

Sooo under that logic, programming may be off and I'd be chatting with Dave to get any info on how he might derive it.

Hmmm phone rang, it's a PA number.

John..

We spoke and did some math. If that doesn't work, speak to Dave. I believe we did it right (which probably means it'll be wrong).

And ... Greg tossed a number at me in chat w/o having been on the convo. Same number.

Hopefully it works out.

You know John.. Pat has some converter issues on his own. I have him a little info/tune and he loved it.

Either way.. glad that worked out.