how much 1/4's time is lost for...


Sold, and Replaced
Staff member
May 24, 2001
hey all, i am changing my tcc selenoid this weekend, b/c i cant get my car to lockup, even after changing the brake switch 2 times (autoparts store sold me the wrong one) didnt knwo it was a special part just like all the rest for these cars. but does anyone know how much 1/4'th time is lost due to the converter not locking up? should it be locking on the track?

*i am trying to tune my car and it's going about 1 full second slower than it should be, but i want to research each lead one at a time to get it tuned right. stock Converter. stock 113k mi trans.

that is the purpose for this post thanks in advance*
As far as I know unless you're using a toggle switch to control lockup, the TC will not lock at the track. The computer is programed to lock the converter only when on the cruising on the highway. When you put your foot into the throttle the computer will not lock the converter to allow the motor to rev higher to make more power. If it is not locking up on the highway there are many things that can cause this problem. First I would replace the lockup solenoid inside the trans. If that does not work I would have it professionally diagnosed. Worse case is you need a new converter. To answer the original question it should have no affect on 1/4 mile times.
you or your chip have to force lockup at WOT....the stock chip will not allow lockup at WOT.....check with your chip is usually an most definitely WILL affect your 1/4 mile times......2-3 mph and maybe .1 if locked in 3rd gear....the most dramatic affect will be observed if you lock it from the get go and lt locks at the 1-2 shift.........note: this is very hard on your converter...results may vary...warranty is void......have seen many converters locked with the "paper clip" method and lived to talk about it...won't work for long if you are making serious power ....but if you still have the stock converter, not an issue
yes it is the stock converter, and i have the manual switch, and a JL chip (he did include somt type of lockup) but i have changed the brake switch, the next step is to test the wire going to the TCC solenoid to be sure that that is working properly then the change the sol or trace the wire back.
With a stock torque converter I wouldn't whole heartedly recommend locking it at WOT at the track. Ya, sure, I did it all the time, but I always wasted the clutch once every year. The stock converter and others with similar clutch designs just aren't designed for that kind of abuse.

As for performance gains/losses, well you won't see much if anything at all ET-wise. The big difference comes in the mph! Generally, with a stock converter, you could see between 1.5-2 mph increase when locking the converter. I always locked it very shortly after the 2-3 shift (and that's how I set it up in my race chip also).

As for a multi-disc converter that's designed for this type of abuse (like the vigillante that I'm now using), it's a little different story. You can lock them at WOT "till the cows come home" with no detrimental affects. I've tried two different ways, manually locking the switch before launch so it lock immediately on the 1-2 shift (that was a huge mistake!!) I don't recommend that method, the vigillante's because of their multi-disc design lock "very positively" and the combination of TC lock and simultaneous gear change is WAY TOO MUCH of an rpm drop, the car boggs badly.
So I went back to my old method of letting the chip do it within about 1.5 seconds after the 2-3 shift. This method works perfectly, and the engine won't drop down out of it's HP/Torgue curve.

With the multi disc design you should in most cases see a mph improvement in excess of 3mph and usually closer to 4 mph.

I'm a mph/power junky and could never go back to a non locking torque converter. There's a lot to be said about getting all or most of your horsepower to the rear wheels instead of eating it up as heat loose in the torque converter.

116.9mph time slips do wonders for the ego when on testing I leave it unlocked and run 113.