More boost at launch

[jnor]

How can you get more boost at launch? My car is a slug for 60' (2.0-2.1) but it runs 13.20's now at 106-107mph.
I can only get about 5lbs with the brakes,my car has a adjustable wastegate can I do something with it to get more boost at lower rpm?
The car wont spin I have BFG drag radials on it. I don't think it would spin the tires in gravel.
The trans and converter seem fine.

The combo is-TA49 turbo,Hooker 2 1/2 exhaust 3" downpipe, no cat. conv.,line loc,trans cooler,volt booster,power plate,237 regulator,K&N filter,3.42 posi,Bfg drag radials,air bag in right rear,Thrasher 93,100,108 chips,(the 100 runs best),the 108 was 3 tenths slower.

I've asked this question several times,but I can never get an answer.

I've never owned a turbo car before and I think that i'am doeing something wrong at launch. It runs 12 secound speed.

How about the emergency brake launch method? I haven't tried it,(about half afraid to).

I don't think that I must buy a torque converter to run 12's, there are a few cars running 12's with stock converters locally.

 

[tim87tr]

This may not be real technical but I just learned launch technique the second time out with my T. Good track prep helps, and build the 5 lbs the brakes will hold. Then mash the pedal to the floor, then release the brake. If the car transfers weight well, and you have air bags and posi, then it will leave hard unless you roast the donuts . You may be running very rich on the low end and it will kill your 60'. You would need more info from a scan tool. I just got lucky with the Thrasher chip, I like them.

I just installed the bigger wheel cylinders (see gntyype.org tech articles) and also went with the soft shoes. Added a line lock for the burnout since I am going to try some 28x9 slicks. The 235 BFGs I used, I just did an easy cleanoff burnout with hardly any smoke. Cottons sells all the parts I mentioned. I have them installed, but my starter died when I was going out for the "testing" of new parts , so that is on hold. With these parts and slicks it is supposed to hold around 10 lbs at the line.

With a good launch you will be into some solid 12s. The stock converter should work with that 49 down into the 12s also.

 

[WSLN 6]

Throw in some S-10 rear brake cylinders. You have to be a little more careful with the rear brakes locking up, but they work pretty good.
After that upgrade, I could hold 10psi on the footbrake.
I went and boxed my lower control arms and installed poly bushings.
I can now hold 14psi boost on the footbrake.
Ditch that 237 regulator ASAP. Get and adjustable regulator and start tinkering.
I ran the time in my sig with 38psi vac off, not the 45psi that your 237 produces.
My car would be way rich with 45psi fuel pressure.
Hope that helps a little.

 

[KEVINS]

I think the surest way to have more brake pressure is to get a jumper valve. I still have stock brakes and brake cylinders but I just push on the brake pedal extremely hard to hold my launch boost of 15psi. Some cars still can't do it no matter how hard you push and IMO it is the proportioning valve causing it. The larger wheel cylinders and brakses still seem to be a 50/50/ shot on some cars but the jumper vavle seems to be 100%.

ks

 

[tim87tr]

Originally posted by KEVINS
I think the surest way to have more brake pressure is to get a jumper valve. I still have stock brakes and brake cylinders but I just push on the brake pedal extremely hard to hold my launch boost of 15psi. Some cars still can't do it no matter how hard you push and IMO it is the proportioning valve causing it. The larger wheel cylinders and brakses still seem to be a 50/50/ shot on some cars but the jumper vavle seems to be 100%.

ks

Darn, I wish I had known that before I spent the $$ and time for those parts Haven't been able to test the parts yet since my starter went out, so when I get my mini-starter I will see if it works. I will be happy if it will hold 10 psi

 

[UNGN]

Originally posted by jnor
How can you get more boost at launch? My car is a slug for 60' (2.0-2.1) but it runs 13.20's now at 106-107mph.
I can only get about 5lbs with the brakes,my car has a adjustable wastegate can I do something with it to get more boost at lower rpm?
The car wont spin I have BFG drag radials on it. I don't think it would spin the tires in gravel.
The trans and converter seem fine.

The combo is-TA49 turbo,Hooker 2 1/2 exhaust 3" downpipe, no cat. conv.,line loc,trans cooler,volt booster,power plate,237 regulator,K&N filter,3.42 posi,Bfg drag radials,air bag in right rear,Thrasher 93,100,108 chips,(the 100 runs best),the 108 was 3 tenths slower.

I've asked this question several times,but I can never get an answer.

I've never owned a turbo car before and I think that i'am doeing something wrong at launch. It runs 12 secound speed.

How about the emergency brake launch method? I haven't tried it,(about half afraid to).

I don't think that I must buy a torque converter to run 12's, there are a few cars running 12's with stock converters locally.

This sounds like a header leak (crossover leak or header crack), or the wastegate puck not completely sealing. The T108 Should be quicker than the 100 unless your are getting knock (due to not enough octane) or you have a header leak/ are too rich.

 

[KEVINS]

I just looked at my spelling on the above post and it is terrible! That's what I get for posting while I'm in a hurry..

 

[John Larkin]

originally posted by KEVINS

I just looked at my spelling on the above post and it is terrible! That's what I get for posting while I'm in a hurry..

I just got off the phone with Jason and you shouldn't post here for a few days. Spelling errors are unaceptable.

 

[KEVINS]

LMAO!!