</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Research says I can go down to maybe 30lb svo's? I wonder if my 39.5 bosch's are hard to calibrate?
</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">John, you said that your WOT A/F on the dyno was perfect right, so why would you think the 39.5's are to hard to calibrate? <img border="0" title="" alt="[Confused]" src="images/icons/confused.gif" /> What duty cycle are you running those injectors at WOT?

If you calibration has positive ltrims at WOT on the street then your A/F may be changing on the street, but Jim knows this. I'm sure it's setup.

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Pro Stock John:
<strong>I'm actively looking for 26" slicks.
</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Wanna try a a few back to back runs with 28s vs 26s? I'm likely heading to US41 this weekend if you wanna borrow my 26x10.5 ET Drags. <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

 

Interesting note:

My car made huge power (398 rwhp) with stock heads and a stupid GM Hotcam. I put ARE Stage X 2.08" intake valve LS6 heads on the car, and it made....

411rwhp.

MTI had that car on the dyno for days and days and days, changing everythign about the engine, including moving to the MTI Hammercam, before we finally could come to ONLY one conclusion.

Those ARE LS6 stage (whatever) heads just totally, completely, didnt make jack for power.

Sounds like everyone is chasing small gremlins... Could it just be that the heads on the car dont make power?

Chris

<small>[ October 02, 2002, 10:31 AM: Message edited by: Visceral ]</small>

 

HAHAHAHHAHAHAHAH!!!!!

where's jmX? he had the same no power syndrome.

Ryan
ps- John, just spray it. your ARE heads want you to. either that or put a 6000 stall and monster solid roller in.

 

Of course he had the same problem...

He ordered his heads almost exactly when I ordered mine, from the same person.

Now he has GTP heads on the car and he now has to deal with something else to go fast, because the beautiful C5 of his is making sick LS1 powah.

*shrug*

chris

 

I have a new set of heads on the car, I bought the 02 LS6 cores from SDPC and sent them to ARE.

I have some flow numbers they are okay... Not amazing, but let's say decent. I'll have to go dig them out today.

These aren't the old nitrous heads I had. These don't have huge exhaust port work done, so the mid-lift velocity is supposed to be much better.

And as far as locking the car up on the dyno goes, why bother. I think locking it up on the track is potentially going to lead to blowing the pump. The Yanks get up to like 94% efficiency which is pretty darn efficient. I locked it at the track two times ago and I did not pick up. I will lock it for a pull just to see the number but will not lock it at the track this converter is not loose enuff to warrant that.

 

Thanks for all the input, here is what we are going to do.

1) leakdown
2) new plugs
3) might swap wires after ohming them
4) might swap on some flowtested 30lb svo's
5) test the maf
6) redyno ( with at least one locked run)

Out of all of that, I think new wires and an injector swap is not a bad idea. If I get 2-3% leakdown that could explain a big loss in rwhp. Bad or faulty injectors could be a culprit.

We will do this at Speed Inc. next week.

See, I do listen to you guys. <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

 

Do them ONE AT A TIME! <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Pro Stock John:
<strong>
And as far as locking the car up on the dyno goes, why bother. I think locking it up on the track is potentially going to lead to blowing the pump. The Yanks get up to like 94% efficiency which is pretty darn efficient. I locked it at the track two times ago and I did not pick up. I will lock it for a pull just to see the number but will not lock it at the track this converter is not loose enuff to warrant that.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif"><img border="0" alt="[Banging Head]" title="" src="graemlins/gr_banghead.gif" />

Without a locked converter, the dynojet rpms are way off. <img border="0" alt="[judgement]" title="" src="graemlins/gr_judge.gif" /> I KNOW I explained the rpm/mph issue to you. <img border="0" alt="[fight]" title="" src="graemlins/gr_punch.gif" />

You use locked dyno runs to tune so you have an accurate measure of rpm. You are on the dynojet to tune the ENGINE. It has nothing to do with controlling your TRANNY to acheive the best ET at the track. If you want an unlocked pull, you do 1 unlocked pull to estimate converer efficency (and get a big torque number to impress the ricers <img border="0" title="" alt="[Razz]" src="gr_tounge.gif" /> )

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">I get 2-3% leakdown that could explain a big loss in rwhp</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">ahh no. Those would be VERY good numbers John.

Just make sure whoever does it knows what they are doing. You want no leakage past the valves and the rest of the cyls should be close to each other.
The actual % loss by the rings has a lot to do with the ring end gap size in the motor so I won't toss out a value not knowing how your rings are gapped.

 

I was talking to Patrick from Precision Turbo (http://www.precisionte.com/), and using his software he thinks the combo is working to like 95% of it's potential...

We mostly talked about injectors, but he feels that my combo is making about 500rwhp as it sits BEFORE drivetrain losses. His own Grand National ran and dynoed about the same.

His comments regarding injectors were interesting. I need to check but my injectors are known as the '868' injectors. Good for 625 crank HP. They are 36lbers at 43.5 FP. These injectors need a lot more offset calculation than say Delphi or Lucas injectors. He said they generally tend to run rich at idle and lean up top. He suggested I use an EGT on the dyno. He also felt that SV30's would be too small and would be running at 100-110 DC. But I might try some just to do some testing.

We all know experts never agree but if I dyno and hit 480rwhp locked on radials, and we add in 20rwhp for 9" parasitic loss, his numbers make sense.

I'm kinda interested in the Delphi 37'lbers but I have a trailer purchase to take care of first.

<small>[ October 02, 2002, 04:01 PM: Message edited by: Pro Stock John ]</small>

 

I would go with a in car wideband. I have used egt probes before and they are nice for n2o or blower, but for a NA combo a wideband is a much better tuning tool IMO.
A friend is letting me borrow his right now to dial in my blown 346 and it's just awesome to dial it in under true load acceleration on the road. No guess work invoved in the tune with one of these units in your car.

FWIW,I run 42lb lucas injectors at 60psi and I have no surge or not even the slightest drivabilty issues.
Some guys claim they are hard to tune, but not my set. I have not even needed to change the offset values from stock.
Been running them for over 2 years now.
Steve

 

*sigh*

My car surges at idle after I sit for over a minute.

I think that Patrick's comments along with my history of lean backfires shows that I do run lean up top so I think I really need to look at that, I remember looking my headers yesterday thinking man, the primaries look kind of white.

 

does it run smoother when you first start it up and then after a minute or so when it goes to closed loop get rougher?
If so, it may have problems running smooth in closedloop using the 02's for feedback injector control and you might want to try a openloop program.
I have been trying that out lately and it runs very smooth and crisp.

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Pro Stock John:
<strong>I was talking to Patrick from Precision Turbo (http://www.precisionte.com/), and using his software he thinks the combo is working to like 95% of it's potential...

We mostly talked about injectors, but he feels that my combo is making about 500rwhp as it sits BEFORE drivetrain losses. His own Grand National ran and dynoed about the same.

His comments regarding injectors were interesting. I need to check but my injectors are known as the '868' injectors. Good for 625 crank HP. They are 36lbers at 43.5 FP. These injectors need a lot more offset calculation than say Delphi or Lucas injectors. He said they generally tend to run rich at idle and lean up top. He suggested I use an EGT on the dyno. He also felt that SV30's would be too small and would be running at 100-110 DC. But I might try some just to do some testing.

We all know experts never agree but if I dyno and hit 480rwhp locked on radials, and we add in 20rwhp for 9" parasitic loss, his numbers make sense.

I'm kinda interested in the Delphi 37'lbers but I have a trailer purchase to take care of first.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">John, this is NOTHING someone at somepoint hasn't told you. Patrick is a good guy, at least your listening. However, injectors on an LS1 are NOT rocket science. Hell, even before programming we were able to run 38 & 42lb'ers without "surging" issues.

YOU insist on doing something so "different" that you don't hear what people are trying to tell you.

Why even ask for help?

<small>[ October 02, 2002, 04:43 PM: Message edited by: JAS ]</small>

 

That whole open-loop tuning idea is very interesting.

My car has surged even with two big air holes in the TB and idling at 1100... that's pretty bad I think. I got rid of one air hole and it idles the same not even rougher. I've had these 868's for quite a while and have had driveability issues for a long time, but now it's better Intmd8 really fixed the cold start issues.

 

PSJ...sometimes you make me want to put a gun to my head.

I have been watching the progress of your car for awhile, and you ALWAYS get 10 million opinions on what works, then you twist and tangle it to form "your opinion". Look where its gotten you. Have you ever thought of dropping the car off at ARE, and letting them sort it out? Maybe let them add a fogger to it....that seems to work for them most of the time <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />

I tell ya what.....instead of me sitting here making fun of you(which is WAY too easy), I will make ya a deal. Somehow...get the car shipped down here and I will make it run for you.....free of charge. That includes dynotuning, Ls1 edit, wideband usage, and track time.

I built my 2000 SS one weekend, installed heads/cam.....and went to the track for the first time ~ 1 week later. @ 3475 pounds, the car went a 11.3 @ 118mph on the very first pass, hitting the rev limiter on the 1-2 and 2-3. I raised the rev limit, installed 4.10's, and the next weekend it went 11.0 @ 122, 11.0 @ 123 and a 10.9 @ 123.5........in ~75 degree summer weather and 1.49 60'. AND THIS WAS WITH A STOCK SHORTBLOCK!!! I just don't see whats keeping you in the 11's.....maybe its the lead roof Nineball mentioned <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />

Chris

 

BTW, if those injectors are 36lb @ 100% duty cyle at a 43.5psi test pressure then they are the following in an LS1 58psi

41.57lbs/hr 58psi @ 100%DC
5.24g/sec

665hp Crank HP N/A 100%DC .50 BSFC
532hp Crank HP N/A 80% DC .50 BSFC

 

Oh.. 5.24 is the first value LS1Edit.

Hopefully SOMEONE will pick up useful information in this entire thread of people trying to constantly help you.

Hell, NOW even the OUT OF STATE guys are TRYING TO OFFER YOU HELP FOR FREE! <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" />

<small>[ October 02, 2002, 04:59 PM: Message edited by: JAS ]</small>

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Cmarsh93z:
<strong>PSJ...sometimes you make me want to put a gun to my head.

That was pretty funny <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />

I have been watching the progress of your car for awhile, and you ALWAYS get 10 million opinions on what works, then you twist and tangle it to form "your opinion". Look where its gotten you. Have you ever thought of dropping the car off at ARE, and letting them sort it out? Maybe let them add a fogger to it....that seems to work for them most of the time <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />

Chris</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">I wondered the same thing? specailly back when it was backfiring..

Good Luck john <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />