well done
Dyno done
Thread Starter
Safety Car
Joined: Dec 2002
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From: Charleston SC
Dyno done
Well after what was both a long and frustrating day the motor was able to get 414 RWHP and 413 TQ.The TQ was solid from 350@ 1800 RPM all the way across and peaked at 4.5 tapering off very slow. The part that made it frustrating was a constant miss at 3800 RPM. The car would pull great up to 3800 miss then pull great from 3900 up. This is the strangest problem I have ever encountered. It will miss at all throtle positions, loaded or in neutral, hot or cold and always at the same spot. The fuel preasure holds rock steady, the spark plugs and wires have been changed, the delteq brain has been changed, and we even swaped in a new ECM. The ECM thinks everything is great and all sensors look normal when this happens. I figure its got to be the opti or the Delteq coil pack but am not sure how to check either and realy hate just throwing parts at somthing. Oh well at least the car pulled decent #s and I now. Am open to any and all help on the miss part
Thread Starter
Safety Car
Joined: Dec 2002
Posts: 3,655
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From: Charleston SC
Originally Posted by 65Z01
Did the numbers agree with expectations??
Can you put up the pull curves and your engine buildup?
Can you put up the pull curves and your engine buildup?
The motor is a forged scat crank/H-beam rods, SRP -16cc dished pistons 383 with AFR 195 heads done by more performance with the Comp Promag 1.6 R/R's and CC 306 Cam Shaft. Other stuff, FMS 36# inj, Holley 58mm TB, Stainless LT's, MagnaFlow muflers.
here is the best I can do with my scaner
Race Director
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If it is the logical part of the opti causing your misfire I promise not to say "I told you so." Not you specifically, just everybody who thinks these systems actually solve the opti problem. So long as any part of the opti is still used you're just as vulnerable to the same problems.
Good luck with it, maybe it won't be the opti, but I don't know what else it could be.
Good numbers!
Good luck with it, maybe it won't be the opti, but I don't know what else it could be.
Good numbers!
Team Owner
Joined: Dec 2000
Posts: 90,675
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From: SE NY
Cruise-In II Veteran
FD2BLK thanks for the info; I'm going to enter the data into Dyno2000 to see how close the torque/hp curves match you dyno pulls.
You are really building some nice power there, about 490chp.
You are really building some nice power there, about 490chp.
Thread Starter
Safety Car
Joined: Dec 2002
Posts: 3,655
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From: Charleston SC
Originally Posted by Nathan Plemons
If it is the logical part of the opti causing your misfire I promise not to say "I told you so." Not you specifically, just everybody who thinks these systems actually solve the opti problem. So long as any part of the opti is still used you're just as vulnerable to the same problems.
Good luck with it, maybe it won't be the opti, but I don't know what else it could be.
Good numbers!
Good luck with it, maybe it won't be the opti, but I don't know what else it could be.
Good numbers!
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Burning Brakes
Joined: Sep 2000
Posts: 1,199
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From: NewCastle IN. USA
nice numbers.
the miss at 3800rpm is strange, I don't know much about optispark units but most "mechanical spark related" issues show up worse at higher rpms (things like bad plugs/wires/coil ect).
I'd take a close look at the tune, there may be a small area of the A/F ratio or the timing table out of shape (it could only take one point), also if you have a WOT timing addition (where timing is added or taken out only at WOT) something might be happening there.
shouldn't take too long to check since you can confine your search to the 3600-3800rpm area.
the miss at 3800rpm is strange, I don't know much about optispark units but most "mechanical spark related" issues show up worse at higher rpms (things like bad plugs/wires/coil ect).
I'd take a close look at the tune, there may be a small area of the A/F ratio or the timing table out of shape (it could only take one point), also if you have a WOT timing addition (where timing is added or taken out only at WOT) something might be happening there.
shouldn't take too long to check since you can confine your search to the 3600-3800rpm area.
Race Director
Joined: May 2001
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is there anything that toally replaces the opti? i thought thats what the delteq did...
The other 5 I've seen fail have all failed on the logical side. As such any ignition system that still used the logical side for it's ignition signal is just as dead. Sure the Opti has it's problems all around, and the Delteq and other systems address some of them, but certainly not all. IMHO it's not worth spending all the extra money on one of these aftermarket systems that still uses the same old Opti for it's timing signal.
Am I wrong, nope. Is anybody else wrong for running the Delteq or LTCC systems, nope. Like I said, if it is the Opti, I won't say I told you so, even though I might have to bite my tounge to do it. There's no offense intended, just trying to make a point.
Large Impressive Member
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From: Good health is merely the slowest possible rate at which one can die
St. Jude Donor '04-'05-'06-'07
Great numbers Paul! And at this risk of stirring up any controversy, you made those great torque numbers with 1 5/8" headers, right?
Thread Starter
Safety Car
Joined: Dec 2002
Posts: 3,655
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From: Charleston SC
Originally Posted by ol,RJ
nice numbers.
the miss at 3800rpm is strange, I don't know much about optispark units but most "mechanical spark related" issues show up worse at higher rpms (things like bad plugs/wires/coil ect).
I'd take a close look at the tune, there may be a small area of the A/F ratio or the timing table out of shape (it could only take one point), also if you have a WOT timing addition (where timing is added or taken out only at WOT) something might be happening there.
shouldn't take too long to check since you can confine your search to the 3600-3800rpm area.
the miss at 3800rpm is strange, I don't know much about optispark units but most "mechanical spark related" issues show up worse at higher rpms (things like bad plugs/wires/coil ect).
I'd take a close look at the tune, there may be a small area of the A/F ratio or the timing table out of shape (it could only take one point), also if you have a WOT timing addition (where timing is added or taken out only at WOT) something might be happening there.
shouldn't take too long to check since you can confine your search to the 3600-3800rpm area.
I was right with you on the tune untill yesterday. The tune was compleatly changed and had no effect on the problem. When the car went in it was way lean (160's) and we played with the fuel untill we got it pig rich then the timing. The problem happens at all Throtle positions (Part or WOT) so it realy is confusing. I am thinking it has to be either the opto or the coil pack for the Delteq and will trouble shhot it more tomorrow. As far as the dip at 2500 I think it just wants a bit more fuel looking at the AF I can see a dip that almost mirrors it but we had ben tuning for 4 hrs and I had a 4 hr drive ahead so I decided to call it a day. I will make a trip again for another tune once the other problem is all sorted out.
Thread Starter
Safety Car
Joined: Dec 2002
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From: Charleston SC
Originally Posted by Corvette Kid NC
Great numbers Paul! And at this risk of stirring up any controversy, you made those great torque numbers with 1 5/8" headers, right?
Thanks and yes they are, Hmm might even be te same ones you have
Race Director
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Originally Posted by FD2BLK
Thanks and yes they are, Hmm might even be te same ones you have
A friend of mine tested 1 7/8 headers on a stock displacement heads / cam LS1 car and picked up horsepower and torque clear across the board. I have to believe that stroker of yours could benefit from a bigger pipe.
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From: The Top of Utah
Originally Posted by FD2BLK
The motor is a forged scat crank/H-beam rods, SRP -16cc dished pistons 383 with AFR 195 heads done by more performance with the Comp Promag 1.6 R/R's and CC 306 Cam Shaft. Other stuff, FMS 36# inj, Holley 58mm TB, Stainless LT's, MagnaFlow muflers.
RACE ON!!!
Thread Starter
Safety Car
Joined: Dec 2002
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From: Charleston SC
Originally Posted by CFI-EFI
One is the 58mm TB, and the other is the 36# injectors. Both seem to be overkill for the rest of the combo. In any case, smaller might help fatten the numbers somewhat.
RACE ON!!!
RACE ON!!!
It may seem that way but after speaking with David Koldos I think the 58mm was the right choice, If I get the chance I will throw a 52mm on and run back to back to test your theory because a TB swap is easy enough for extra HP. As far as the injectors go I went with what my tuner wanted to see and they where actualy a little onthe small side. My car was way lean even with the FP set to 50 PSI (160's) but Jeff, the tuner, was able to fatten it up and get the AF (13.2) almost perfect and 128 across the board. I wish I had some clue to what this problem is because I don't like to throw $$$$ at a problem.
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From: Texas
Originally Posted by FD2BLK
It may seem that way but after speaking with David Koldos I think the 58mm was the right choice, If I get the chance I will throw a 52mm on and run back to back to test your theory because a TB swap is easy enough for extra HP. As far as the injectors go I went with what my tuner wanted to see and they where actualy a little onthe small side. My car was way lean even with the FP set to 50 PSI (160's) but Jeff, the tuner, was able to fatten it up and get the AF (13.2) almost perfect and 128 across the board. I wish I had some clue to what this problem is because I don't like to throw $$$$ at a problem.
Also, 128 across the board means nothing. You can't effectively tune WOT with the fuel trim numbers. As an aside, some of the tuning software has a fuel trim blocker. At WOT the fuel trims jump to and lock at 128. This is done so that WOT fueling is consistent and is a modified by the power enrichment tables only.
Thread Starter
Safety Car
Joined: Dec 2002
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From: Charleston SC
I though the factory ECM looked for 14.7:1?
I doubt the problem is a lean miss fire because we had it so rich on one run it was billowing black smoke and it still had the miss fire.
I doubt the problem is a lean miss fire because we had it so rich on one run it was billowing black smoke and it still had the miss fire.