Torque Converter Question
Thread Starter
Burning Brakes
Joined: Oct 2003
Posts: 1,090
Likes: 74
From: New Carlisle IN
Torque Converter Question
I autocross my 76 vette. It has the stock L48 with 71 heads and 80 aluminum intake so it isn't exactly powerful. It has a TH350 tranny and the 3.08 rear gears. I just tore up the tranny and torque converter and will be looking to put new ones in as i can afford them.
My question is, what RPM stall is good for a torque converter for a low HP car running an autocross? Keep in mind, I need to get off of a corner and up to speed as quickly as possible. Is a lower RPM stall better for this or a higher RPM? I just don't know how the torque converter actually works.
My question is, what RPM stall is good for a torque converter for a low HP car running an autocross? Keep in mind, I need to get off of a corner and up to speed as quickly as possible. Is a lower RPM stall better for this or a higher RPM? I just don't know how the torque converter actually works.
Melting Slicks
Joined: May 2012
Posts: 2,192
Likes: 343
From: Allenton Wisconsin
a torque converter is a fluid coupler. there is no direct connection between the engine and trans like with a std trans. the inside of the tc has fins that catch the oil. the outside case of tc spins at engine rpm. the inside turbine is connected to the pump and input shaft of the trans and as the rpm of the outer case increases the oil caught turns the inside turbine. a higher stall tc allowes the engine to rev up higher before maximum oil connection is made. in a car with auto trans when cruising, lets say 3000rpm as soon as you let off the go pedal the engine drops rpm even though the vehicle speed has not decreased yet. this is evidence of the amount of tranny rpm input loss due to the oil coupling in the tc. remember stick cars always got better mileage and now all new auto cars have lockup tc's. hope this helps, maybe another member can help with that stall speed question.
Le Mans Master
Joined: Aug 2010
Posts: 9,272
Likes: 17
higher stall works with drag racing, the extra heat will kill your next trans also cause your not doing 1/8 or 1/4, your'e out for 5 minutes to a 1/2 hour... depending. a lower 1st would get you out of the corners faster, a better swap would be to a manual 4,5,or 6 speed trans. while you have it out, now would be the time. hope this helps
