If this is in the wrong board, go ahead and move it.
I have heard that to launch an automatic car, you have to stall the torque converter, by pressing the brakes down and then the gas as far as you need. It preloads the transmission and is safer than N-D drops. But I believe I heard that the torque converter will multiply torque and in some cases(traction permitting), you can autlaunch a manual of the same car. Of course, the top end suffers, but I was wondering if the part about multiplying torque is true. Is it?

 

Yes, most converters give you a 2 to one ratio. So 100 ft pounds with a stick
would be 200 with a auto. The hard part with a auto is getting the rpm up high
enough to get into the power range. If you stall at 2500 rpm and your engine
makes power at 5000 rpm, it's a long slow haul to gain that 2500 rpm.

A little shot of juice will do wonders though....

Some cars will leave better if you flash the converter. Punch it from a idle and
the converter will flash to a higher rpm then stalling with the brake.

Steve

 

Thanks for the info.

 

its not good to "powerbrake" an automatic tranny. The results of doing this create a lot of heat and can damage the transmission over time because the transmission fluid overheats and loses its protective properties.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mastarolla &raquo;</TD></TR><TR><TD CLASS="quote">its not good to "powerbrake" an automatic tranny. The results of doing this create a lot of heat and can damage the transmission over time because the transmission fluid overheats and loses its protective properties.</TD></TR></TABLE>

This is very true on a Honda tranny which are very weak even with a stock DX motor pushing it.

 

I wasn't going to do it with my dx, but thanks.