what does STR mean when looking at converters? most are like 2.5,2.2 or something?

 

I just copied and pasted this from a previous thread the other day. Hope this makes sense.


STR = Stall Torque Ratio

Higher STR converters pass more torque to the wheels thus creating harder launchs. Stock converter is a 1.6 STR if I'm not mistaken and some of the top all out race converters are around 3.0 STR. Most aftermarket torque converters are in the twos. On paper it sounds like the higher the better. For trailer queens running slicks and 12 bolt rear ends this would be the case. But for daily drivers with occasional track duty you may want to be a tad more selective.

Anything under 2.0 will hit the tires relatively soft at launch and be somewhat usable with street tires. Anything 2.0-2.5 is considered enough to roast street tires and then Drag Radials full time are almost a must. Even then you have to fether the gas a bit as we can't do a 8 second burnout on the street while heading to work/school. Anything 2.6-3.0 will be a very hard hitting race converter that hit so hard Drag Radials can be roasted if you don't use extreme caution. For the most part you need slicks in the back to launch those converters to thier potential.

My personal thoughts on STR is 1.8 - 2.2 are street/strip but more aimed at the street. 2.3-2.6 is street/strip but more aimed for the strip (with drag radials a must). Anything over 2.6 and you better be running slicks and on a track or you will have to baby the accelerator.

Hope that helps explain it.

 

dang thanks a lot. thats pretty much what i wanted to know. thanks again