New torque converter track results

[MaxedGT]

I just installed a 3500 rpm stall 9.5 inch converter and went to the track for the first time on the 1st. ran a best of [email protected] mph with a 1.950 60ft. I,m not happy. Previous best was 13.41 @ 103, with a 2.01 60 ft. Only a slight improvement in the 60 and 330, but a loss of 2 mph for a net gain of zero. One night out isn't conclusive so I'll try again this coming friday. I was spinning a little on the launches so I need to work on getting more grip and see what happens. I didn't expect traction issues with the M/T streets but the track is a little green. I think I might need to pull it and have it restalled.
Any advice?

 

[CobraRed_96_GT]

a higher stall and smaller TC saving weight wont cause you to lose mph, basically ever if it's locking. My guess is it's just making it harder to get great traction

 

[MaxedGT]

It's not locking. I was trapping at 5200 rpm. stock I trapped at 5000. I'd still have to get a custom tune to lock it at full throttle. I figured I concentrate on my 60 ft before making any more changes.

 

[MaxedGT]

Cobrared, whats yours like under normal acceleration city driving. Mines like driving a constant Variable transmission. Rpm's are around 2000 rpm, shifts barely noticable, until lockup.

 

[CobraRed_96_GT]

It should be locking up for sure, even under full throttle. Around the city under part throttle it's hardly noticeable over stock, only the idle creep is much different. I've been in a 3600 stall car similar to my power curve and it isn't like what your describing at all.

 

[navarro98gt]

Cobrared, whats yours like under normal acceleration city driving. Mines like driving a constant Variable transmission. Rpm's are around 2000 rpm, shifts barely noticable, until lockup.

You need to get that thing tuned. I just ordered a 4000rpm stall speed converter from B.C. Auto and Darrin said without a tune the shift points will be all messed up and it might not lock up properly.

 

[MaxedGT]

I'm going to try it out again at the track and work on my 60ft. I'll data log my runs too so I can see what's happening. No point getting it tuned till I know if I'm going to stay with the current stall. Maybe I should drag out my old drag radials that I have more experience with. They're bald now but they sure worked good for me.

 

[bhuff30]

Converter lock up can make a big difference on your trap speed, and a 2mph loss is reasonable. The trap speeds in my 88 are always a bit slow because I can't lock up the converter.

 

[MaxedGT]

I was hoping for a little less loss in trap speed and expecting the 60ft time would more than make up for it. Maybe I was expecting too much.
Does anyone know a way to determine if the stall is too high? I guess I need to pay more attention to the tach and less to the staging lights till I get this figured out. lol.
The competitor in me got the best of me.

 

[bhuff30]

I would think a couple hundred rpm below peak torque would be the highest you'd want to go on the stall speed.

I think you will see nice gains once you get everything ironed out. As you said, the converter isn't locking now, which hurts a bit. Also, you said you were spinning the tires. You may have to find a different launch technique so you don't shock load the tires as hard on the initial launch. We all know MTs are good for better than a 1.9 60' time. Sort out these two issues and you'll probably find two tenths improvement from your previous best.

 

[MaxedGT]

If I can only gain 2 tenths from my previous best, the stock converter is going back in. I'm expecting to improve by at least 3 tenths, once I get things ironed out. I was hoping for 5 tenths based on other threads I've read. I've been sick with the flu for the last 2 weeks and haven't made it out to the track which really sucks.

 

[MaxedGT]

I'm going to unhook my sway bar, and try dropping the pressure in the rr airbag, to try to get more grip. any other tips?

 

[ran260gt]

That really sucks , how much tire spin are you getting , are you losing time before or after the 1/8 ?


And man what a relief , I was worried you beat me to the 12`s , j/k , I think you still have plenty of time , I dont think I will be getting back to the track this season , Im having some shifting problems , think my Interm. Clutch or Direct Clutch is giving up on me !

 

[MaxedGT]

That really sucks , how much tire spin are you getting , are you losing time before or after the 1/8 ?


And man what a relief , I was worried you beat me to the 12`s , j/k , I think you still have plenty of time , I dont think I will be getting back to the track this season , Im having some shifting problems , think my Interm. Clutch or Direct Clutch is giving up on me !

Damn your problems are worse than mine. Sorry to hear it.
I don't think I'll be hitting the 12's at my current power level. Not without weight reduction, and that's not a route I want to go.
I'm actually pretty even at the 1/8th but my speed is down about 1 mph. I don't really know how much I was spinning because my ears were plugged from the flu that I came down with that day. I couldn't hear the tires over the exhaust. lol.
I was there alone, so nobody to give me feed back.
I'll have to get a custom tune to lock up the tcc at full throttle in 2nd and 3rd, and work on get my 60 ft down. The car feels and sounds faster but the seat of the pants dyno means nothing.