Transmission heat vs. ET/Performance

[Chipper Chapman]

As the transmission fluid gets hotter, how will it affect the converter? Do you guys tend to see your cars get faster as trans temps go up? I have noticed a trend in my car I can only partially explain to myself. As the rounds get tight and start “hot lapping” the car will gradually get faster and faster, I have watched engine coolant and oil temps, and obviously it like hot oil and cool water which I can keep under control and keep tabs on. I don’t have a trans temp gauge so I can’t see what it’s doing. But a few times now on hot laps (usually going into semis or final) the car will pickup .04-.06 out of nowhere, right off the hit. It’ll usually go the best pass of the weekend on the brakes. So I’m wondering if hot fluid in trans effects the way the converter works that much.

[Adger Smith]

Hot fluid usually loosens the converter. It also seems to loosen sprag drag.
I had a Local Bracket race customer that watched temps and noticed the better ET's .. ESP. changes when he sat and cooled a bunch. We went to a spargless converter and helped the situation. A lot goes on with temp changes.

[Chipper Chapman]

Understand. So if the heat loosened converter it could also be a sign the combo wants a looser converter as well, correct?

[Adger Smith]

Yes, the converter might not be optimal if it is just the converter stall/flash.

[jmantle]

Originally Posted by Chipper Chapman

As the transmission fluid gets hotter, how will it affect the converter? Do you guys tend to see your cars get faster as trans temps go up? I have noticed a trend in my car I can only partially explain to myself. As the rounds get tight and start “hot lapping” the car will gradually get faster and faster, I have watched engine coolant and oil temps, and obviously it like hot oil and cool water which I can keep under control and keep tabs on. I don’t have a trans temp gauge so I can’t see what it’s doing. But a few times now on hot laps (usually going into semis or final) the car will pickup .04-.06 out of nowhere, right off the hit. It’ll usually go the best pass of the weekend on the brakes. So I’m wondering if hot fluid in trans effects the way the converter works that much.

My car does the same, picks up if I hot lap it. I tried warming the transmission up thoroughly before a pass and that doesn't seem to make a lot of difference. I think it's a combination of everything more than just the transmission.

Jim Mantle V/SA 6632

[Chipper Chapman]

Originally Posted by jmantle

My car does the same, picks up if I hot lap it. I tried warming the transmission up thoroughly before a pass and that doesn't seem to make a lot of difference. I think it's a combination of everything more than just the transmission.

Jim Mantle V/SA 6632

I’ve been able to monitor the oil and water temp and it doesn’t seem to change much, but I don’t have a way to monitor the trans temp hence why I’m leaning toward it causing the bulk of the issue. Also I currently don’t have a trans cooler the lines are just looped.

[MEXJOE]

You need a trans temp gauge. You will find 150F and above will give Lower ET. The hotter you get it the faster it will go. Of course there will be consequences....