Went to the drag strip tonight.....now some questions.

[dgreene]

I went to the loacal 1/8th mile track to night to try and get some times on my 87 GN with the astroroof. I run a 8.68 with some very poor reaction times(could have been a 8.48 if I hadn't dozed on the line.) Here's the deal, I leave the line with 5 PSI it almost instantly jumps to 19 PSI( I had added some xylene to the mix along with marvel mystery oil) then falls to to 15 PSI then eases back to 19, then on the 1-2 shift it falls to 15 then climbs back up again. There is a slight leak with the drivers side header, but I mean it's slight. Maybe it could be something else? Any ideas?

I have the DirectScan of the run if anyone would mind looking at it and give me some suggestions? It didn't do this with the stock turbo and I haven't run the TA-49 to much, but I was under the impression that it would spool and act much like the factory turbo. If anyone would look over the DS file just let me have you email and I will mail it to ya.

Oh, met Joe Tiano tonight at the track. I plan on getting a laptop stand from him since it's almost imposible to see it sitting in the passenger seat while looking at the track.

 

[jastrckl]

Fix the header leak before even bothering troubleshooting this at all, IMHO. as for the reaction time, it has no effect on ET. ET starts when the car moves and trips the light. what RT -does- count in, is bracket racing.

 

[gnnovas]

After the exh leak, look for a leak on the pressure side of the turboto the intake. I had a hose clamp at the exit lose. It would spike then drop way back and take awhile to build boost back.

Ken
87 GN

 

[Joe Tiano]

dgreene...IF you have a slight header leak...it's probly BIGGER than you think!I can weld your header for you!...it was nice meeting you...I'll be bringing my gn to shadyside in a few weeks...maybe we can BS some more...later joe

 

[dgreene]

Thanks guys. I'll get my father to weld that header over the weekend and test that out. If that doesn't fix it(the header) I'll send it to Joe. Then look on the preasure side if that doesn't work. I also need to get my "death"master rebuilt this weekend, but I should have plenty of time for that.

Thanks for the offer Joe! Yeah, now that I've been over there again, I'll keep going. I tell ya what, I'll measure my laptop and send you the specs, and I'll bring cash for ya if you can get it made in time for when you come down.(or I could just send you the money if not). I'm glad to have run into a friendly turbobuick guy who will be on and off at the local track.

 

[V6 Beast]

Shadyside? I hope you will be wearing your bullet proof vest. Let me know when you guys go and I will bring my GN and my Smith and Wesson and meet ya'll


Reaction Time has no affect on your times. Are you controlling boost with chip? or some type of manual controller?

Send me the DS runs and I will look at them.


Sully

 

[dgreene]

it's chip controlled. I could have swore when using the bracket tree, that the reation time had some to do with it.....guess I was wrong. Hell it's been 8 or so years since I had been.

Yes, this is at Shaddyside. Hope you're a quick draw!! Some of those guys are pretty fast. I prefer body armor though.....

 

[V6 Beast]

I have never been able to get a decent 60' at Shadyside. Ya'll should try Mooresville . No need to carry there.

Send me the DS file. Email

Sully

 

[dgreene]

Thanks for looking over those DS files! Sorry about the first email, I pressed send before I attached the two runs. Should have made it one the second one though.

I think Joe had some pretty good times at Shadyside......Maybe he will chime in and let us know. I'm sure he told me, but we went on about alot of things and I can't remember what he said he pulled at the 60'.

 

[V6 Beast]

TPS is pretty low 1st run.. much better on the 2nd. Looks like your chip is calling for constant boost in 1st & 2nd and a little less boost in 3rd. This must be a basic street chip. You are way rich.. may want to turn starting fuel pressure down or crank the boost up a bit. Your maf doesn't stay maxed for the whole run, but may be normal if you have stock turbo.

HTH

Sully

 

[dgreene]

I readjusted the TPS for the second run and also upped the boost. I raised it some more, but didn't get a third run because of rain. The MAF would fall as the boost did, then would max out as it went back up. My combo is in my sig. , I was running the astroroof car. The chip is a pretty standard street chip from Jim Testa. Maybe the overly rich deal hurt the spoolup?

I think with a race chip, some more boost(and steady boost), some more tuning and a little better launch I hope to hit 8 even or better. Do you see that as problem?

 

[V6 Beast]

I am surprised it is so rich for a street chip especially since you weren't running that much boost. Most street chips are only setup for 17-18 PSI. What was your fuel pressure at idle?
Properly tuned, a Ta-49 and 50's should be able to run in the 7's no problem.

I am surprised your MAF dropped off like that, but it has been a while since I looked at relatively stock setups. May be dropping off just because of the low boost, stock heads or maybe weaker vavle springs.

I would think that with good gas, 26º race chip and 22-23 PSI boost, you should be able to crack off a high 7.

It is pig rich on the bottom which can slow your spool time.

HTH
Sully

 

[dgreene]

I'm pretty sure that the fuel preasure is 42# line off. I'm getting ready to go to my shop so I will be working on it. I'll also try another chip that I have to see if it changes the spool up and the rich condition.

Thanks for all the help!

 

[dgreene]

Well, I checked the fuel preasure, it's 42#s line off. Since I had been having trouble with my powermaster I decided to rebuild it. It is now rebuilt with new accumulater. To bad the pump is also weak. It will never pump all the way up and cut off, just like before the rebuild. At least now, it doesn't take all my strength to push the pedal. Of course those 2 o-rings that were ruined inside had a little to do with that. Any of you guys know who it was that was selling the powermaster pumps awhile back? I need to get to stopping good before I worry to much about going faster!!

Great weekend........