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· got twins?
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Discussion Starter · #1 ·
Hey guys

Quick question about launching. I have a BPU auto with a 3600RPM stall. Last night, I took it to the 1/8th to practice my launches as I have been launching at only 2500RPM previously. At 3000 RPM, my rear tires spin (275 BFG Drags) while sitting at the light. I have my foot firmly on the brake - is this where I need to pull up my e-brake? My best 60 foot has been a 1.9 and from what I understand, I should be able to hit at least a 1.7 - what am I missing? Could I have a possibly have a 3200 RPM stall instead of the 3600 I ordered? Thanks for the input.

Anna
12.3 @ 116mph best 1/4
7.9 @ 88mph best 1/8
 

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bikiniracer said:
At 3000 RPM, my rear tires spin (275 BFG Drags) while sitting at the light. I have my foot firmly on the brake - is this where I need to pull up my e-brake?
Yes, you should be pulling the e-brake up.


John H
 

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I'm with john, I would hold down the foot brake as hard as you can and hold up the ebrake as hard as you can in staging, I've pulled 1.6s on drag radials back when I was on stock twins.

Good Luck.
vnt :bigthumb:
 

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That may help but there is a good chance you just didn't get the kind of stall speed you wanted. Maybe the company screwed up or it may just be that TCs stall differently for different cars and yours is stalling low.
 

· its a slow auto...
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VeilsideTT said:
That may help but there is a good chance you just didn't get the kind of stall speed you wanted. Maybe the company screwed up or it may just be that TCs stall differently for different cars and yours is stalling low.
her problems are related to her brakes, not the converter.. the only real way to check a stall speed is against a trans brake, which she obviously doesn't have... her rear brakes are being overpowered, which is why she needs to help them out by using her ebrake to up the braking force :) once she does this, she will have a better idea of where the converter will go as far as stall rpm.. if i foot brake my car it will only go to about 28-3k and then spin, if foot and ebrake it i can bring it up to 38-3900 without a problem and build 7-16psi if i want...

jay
 

· Bad Karma Supra
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If you don't want to get into all the ebrake non-sense - I'll get into recommending a small shot :D
 

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jaynite said:
her problems are related to her brakes, not the converter.. the only real way to check a stall speed is against a trans brake, which she obviously doesn't have... her rear brakes are being overpowered, which is why she needs to help them out by using her ebrake to up the braking force :) once she does this, she will have a better idea of where the converter will go as far as stall rpm.. if i foot brake my car it will only go to about 28-3k and then spin, if foot and ebake it i can bring it up to 38-3900 without a problem and build 7-16psi if i want...

jay
True, but assuming she has regular TT brakes that aren't completely shot, can't we assume that she's getting less stall than she wanted and less stall than other people who also ordered similar converters?

Bikiniracer, where does the converter flash to when you gun it?
 

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you never mentioned a burn out... if you heat up the tires (good 5-10 seconds of smoke) they should stick to the ground better...

also, try dropping the tire pressure to see if that helps (or if you have a infrared heat gun [bout $70 in JEGS] check temperatures across the contact patch of the tire: they should be even)

here is a method for improving braking power...
1. roll up to the light
2. go into neutral, rev a bit, then let rpms fall off
3. you will notice that vacuum dips lower then it normally would be
4. smash on the brake pedal as hard as you can
5. now get into gear and stall it up

additional vacuum in brake booster = more braking power
 

· Bad Karma Supra
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Damn, you guys are rough!!! My turbo is NOT massive :D Don't hate me...hate NX ;)

swearitsstock - is right about getting the brakes to hold harder though
 

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bikiniracer said:
Could I have a possibly have a 3200 RPM stall instead of the 3600 I ordered? Thanks for the input.
When I ordered my stall I thought it was a 3,400rpm stall. I recently had BL build my tranny and Kean checked on the stall speed. He ran the numbers off the converter with PI and it turned out to be a 3,800rpm stall. So you can double check by contacting PI.

Additionally, you will not be able to stall it up all the way up at a light (from experience and what I have been told). For example, I cannot get my converter all the way up to 3,800rpm. Most I have seen is around 3,300. So if you have a tight converter, keep that in mind. :bigthumb:
 

· got twins?
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Discussion Starter · #16 ·
Thanks guys for all the advice/tips. I'll be running again in Alabama in 2 weeks so I will let you know how it does. I'll drive it tomorrow and tell you what it flashes to when I punch it...

Swearitsstock...if I got this technique down AND then gave it a small shot, hmmmmm.

Keep the ideas coming.

Anna C.
 

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swearitsstock said:
shot is not a good idea if you are on stock fuel and running MAF... NAWSSS makes street cars go BOOM

get AEM and convert to speed density... then add a wideband AF and youll be straight for a small shot
no



John H
 

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John H said:
no



John H

John hates Nos... it would help you out and do it without harming your engine... "IF" you use all the safety gadgets.. (window switch, Fuel cutoff, throttle position sensor).

However, you should not need it for a good pass.
 
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