I have a friend with an automatic C5 corvette. I am trying to get him to bring the corvette out to some of the local road course track days. Is there anything to worry about when lapping an auto trans corvette? I was wondering if they can take the heat developed during a 30 minute session. The car is currently in stock trim.


We also talked about a final drive gearing change, and maybe replacing the torque converter for more straight line performance. Is there anything to plan into the modifications if the car goes out to the road course once a year?

 

 

Best option would be an aftermarket bar/plate cooler for the tranny. Don't use one of those tube/fin coolers, they are worthless for the high temps it will see. If you can't do that for some reason (and really, a cooler would be the 1st and only option, IMHO), replace the fluid before and after the event. It might not be a bad idea to at least replace the fluid after the event even with a cooler.

I've been auto-xing an automatic for three years. It gets a fluid change every year regardless of mileage. If i were to do any track days like that, a cooler would be a must. Heat is the enemy for an auto.

 

Just get him out there. No special things needed just to start to drive.

He will need to learn to downshift at the end of the brake zone, then upshift after the corner. Dont really want the auto trans to do the shifting. That is when things get too hot.

Synthetic ATF trans fluid keeps the trans much cooler. and synthetic gear oil in the diff does the same. There are lots of ppl who say dont put synthetic ATF in your transmission. Well keeping temps down and better performance is why you DO PUT synthetic ATF in the transmission. PLUS synthetic gear oil in the diff.

take a high pressure air hose and clean out the radiators is a must. the Radiators get soo dirty and ppl never clean them out.

First dot 4 brake fluid and new brake C5Z06 brake pads.

If he is going to do lots of events then yes a bigger trans cooler

Have fun

 

 

I don't autocross but I notice temps I don't like in my auto just from daily driving. I have purchased RP fluids for my transmission, diff and engine and will be reporting if there is any cooler running with those fluids. In daily driving stop and go traffic I can notice temps over 200F which is far too high for the transmission if you ask me. The factory cooler for the transmission is nothing to brag about as I belief it is the typical line-through-the-radiator crap. Since the tranny fluid goes through there it would easily see the same temps as the engine coolant, which I figure Chevy would have given more thought to. Anyways for racing I would definitely invest in an aftermarket cooler as stated by others. Heat oxidizes the fluid and causes it to break down. I have been told by a rep at a very reputable Corvette performance and race team that the fluid begins to oxidize around 260F but of course you don't want to get near that range ever.

-Alex

 

He should be OK, I take mine out occasionally though tracking an auto takes some getting used to and I feel I lose some sensory input and control through the braking zone over the manual track toy. Have him set the DIC to monitor trans temp and if it starts getting too hot pull it in and let it cool off. A trans cooler is a great idea, for under a hundred bucks I think it's super cheap insurance. As you're in Colorado he should probably leave the built in cooler in the loop though, it works like a pre-warmer in cold weather. If you were in Florida or don't drive it when it's real cold out I'd lose it though. Plum the aux cooler in BEFORE the radiator cooler. Yes, it will pick up a bit of heat running through the radiator, but not that much and you DO want it when it's real cold out.
A manual would definitely be my choice for competition, but track days ain't competition and are for grins anyway and I have a ton of fun when I take the auto out. Hell, Jim Hall kicked @zz with an auto in Can-Am, well more of a lockup really, but you get my point.
Main thing is to monitor the tranny like you do everything else and treat it like brake fade and back off or park it for a while if it gets too hot.