Boost at the line

[SRGN]

1 PSI launch worked with my old GN combo. Lit the pre-stage light, brought the car up to 1 lb and bumped in. Best 60' with this method was 1.52. Stock engine, TE63-1 turbo, AC 16930 TC, 3.42 gears and 275-60-15 MT radials.

[jurassic five 7]

Originally Posted by 1chance

No i have a G-tech, it tells me 60ft, RWHP, 0-60, G-Force,1/4mi,1/8mi, and MPH.

OH JEEEZ!

My 1989 G20 Conversion van with 200k on a 305 TBI was running 15's and hade 290 HP , while cutting 1.8 60 foots with my buddies G-Tech.

I guess my van has 290 hp because the G-Tech says so!

You CAN NOT rely on a G-Tech for performance/60 foots/hp.....

-Adam

[1chance]

Originally Posted by jurassic five 7

OH JEEEZ!

My 1989 G20 Conversion van with 200k on a 305 TBI was running 15's and hade 290 HP , while cutting 1.8 60 foots with my buddies G-Tech.

I guess my van has 290 hp because the G-Tech says so!

You CAN NOT rely on a G-Tech for performance/60 foots/hp.....

-Adam

Well, i checked my G-Tech a Jackson Motor Speedy Way! Jackson SC. It was 1/100th off on the mph, all other times were dead on. Im not trying to impress anyone, my car hasnt ran good for long since i had it. When it did, it did ok. No suspention mods to the car, but the first owner heated the front springs before i got it, and the car has no suspention travel in the front. That maybe why it 60 ft so well. I know when it launch the rear hits the bo0ttom of the car. All stock engine at the time with a D5 convert, and a T44, 36lbs injt. Best time was a 12.30 1/4,at 116mph.

[D-mo]

What's up everyone!

[waddell87]

Originally Posted by 1chance

Well, i checked my G-Tech a Jackson Motor Speedy Way! Jackson SC. It was 1/100th off on the mph, all other times were dead on. Im not trying to impress anyone, my car hasnt ran good for long since i had it. When it did, it did ok. No suspention mods to the car, but the first owner heated the front springs before i got it, and the car has no suspention travel in the front. That maybe why it 60 ft so well. I know when it launch the rear hits the bo0ttom of the car. All stock engine at the time with a D5 convert, and a T44, 36lbs injt. Best time was a 12.30 1/4,at 116mph.

WOW Hard runnin car, what was your 60' and 1/8th on that one? if you don't mind me asking.

[1chance]

Originally Posted by waddell87

WOW Hard runnin car, what was your 60' and 1/8th on that one? if you don't mind me asking.

The car got a 1.57-60ft, it average was 1.5-1.6, Im not sure what the 1/8 was. all i had was BFG 26' DRs. I really dont like the way the front end has no play, because i stop at all rail road crossing thinking i will hurt something, but the taller tires give it a good ride.

[CliffyC]

"Here's my story, sad but true..." (opening line to a '60's song...who knows what song?) Anyway, I've wasted two cranks by holding down on the throttle too long at the line. You'd think I'd learn after the first time. Got to be carefull when power brakeing as it builds up line pressure in the trans. This in turn either forces the converter forward or balloons it out forcing the crank against the thrust bearing. If your lucky only the bearing will be damaged, but most likely the thrust face on the crank will be scared. This is very difficult to repair, if you even wanted to, as welding back the face you must avoid the rolled fillet area on the journal. Has this happened to anyone else?

[DonWG]

That has nothing to do with your launching procedure. It has to do with how the transmission was setup. Get the transmission corrected!

[CliffyC]

That's good to know! Just going by what my machinest told me. Can you be more specific? What needs to be done on "how the transmission was set up"?

[DonWG]

The torque converter is being over-pressurized. Judging by your sig, are we talking about a 200-4R? What kind of work has been done to it? Who made the torque converter?

[CliffyC]

Yes, it is a 200-4R. TC was bought from PTS Extreme Trans in Wilton CA. Don't know who exactly made it. Strange looking beast. (see pix) Trans was built locally (Portland) by a knowledgable GN guy. Here's a list of the parts and upgrades; 10 vane pump kit, Alto Red clutch kit, Art Carr hardened forward drum, bushing kit, center support (core), Hardeded stator support, Pump (core), shift kit, Superior super servo, Alto wide band, Thrust washer kit.

[LV GN]

i leave at 6000 rpm's at 35bs. of boost and get anywhere from a 1.08 to a 1.18 60 ft. with the new adjustments to the 4link, the front end is staying down where it belongs.

[DonWG]

CliffyC. Do a search in the transmission section. Try crank thrust wear or problem. I've written much on the subject in a few threads there. This isn't really the thread or section to discuss it. After reading over those threads, if you still have any questions, revive one of the threads over there.

[GO FAST]

I've heard of this problem happening when the converter is'nt properly installed . I personally keep turning it by hand and pushing it on the output stator till it wont go anymore , at least 2 -3 clicks .

[DonWG]

Originally Posted by GO FAST

I've heard of this problem happening when the converter is'nt properly installed . I personally keep turning it by hand and pushing it on the output stator till it wont go anymore , at least 2 -3 clicks .

That will more easily result in a wiped out front pump in your transmission. The torque converter ends up trying to push the pump rotor through the back of the pump. The back of the pump (the pump cover) is made of aluminum, so that damage happens very easily and quickly. It usually will happen so fast, you won't get the car around the block before it stops moving. That's exactly why you want to make sure you have free clearance between the torque converter and flexplate before bolting it up. If the front pump of the transmission is fine, that wasn't the problem.

[CliffyC]

Don,
Lots of good info in past threads inre. thrust bearing and crank damage. Thanks for the help

[imjoesnuffy]

Originally Posted by LV GN

i leave at 6000 rpm's at 35bs. of boost and get anywhere from a 1.08 to a 1.18 60 ft. with the new adjustments to the 4link, the front end is staying down where it belongs.

Now that's just showing off. I saw you run at BG last year, very nice.

[Speed_Dreamin']

Alright, what gives? I have only been to the track w/ my GN once. Launched at 5 psi off the foot brake, Nitto 275/50 DRs, pass air bag (no other suspension mods), w/ front sway bar in place. Netted 2.0 60ft times with what felt like 0 tire spin! Where is all the low end power? Car has a
TA49, 009s, 3in DP, 2.5 in duals, stretch stock location intercooler. Likely with worn out valve springs. Anyone?

[imjoesnuffy]

Originally Posted by Speed_Dreamin'

Alright, what gives? I have only been to the track w/ my GN once. Launched at 5 psi off the foot brake, Nitto 275/50 DRs, pass air bag (no other suspension mods), w/ front sway bar in place. Netted 2.0 60ft times with what felt like 0 tire spin! Where is all the low end power? Car has a
TA49, 009s, 3in DP, 2.5 in duals, stretch stock location intercooler. Likely with worn out valve springs. Anyone?

I am no guru at this, that's why I started the thread but...

Can you launch with more boost? Next time to the track, have someone verify that you aren't getting tirespin. Videotape it if you have to.

I have read on here that removing the front sway is worth 2 tenths. Makes sense to me as it would allow for more front end suspension travel and shifting the weight back on the car, allowing for more pressure to be applied to the rear tires. Play around with tire pressure and find what the car likes, same thing with the PSI in the airbag.