-40* Timing?
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-40* Timing? Well we've pretty much got all the bugs worked out, O2 harness is fixed, MAF, Opti Harness, everything but the car still pops really bad out of the exhaust. We thought it was the rockers arms but I have adjusted them about 10 times myself and another, more experienced person has adjusted them about 5. Now they are Comps Roller Tip 1.52 rockers and we are adjusting them the stock way like it says in the book, this shouldnt be a problem should it? Also the other problem is the timing, on my computer which is tuned for my cam it shows -40* timing, usually it is around -20* but it will jump around. We swapped computers with another car which was tuned for a similar cam but not perfect to see if it would still pop, well its at +40* timing and the car still pops really bad, backfiring a lot, Anyone have this problem? Anyone have any suggestions?
Is the igniton sparking on all 8 cylinders??
I had my car running mostly fine at idle, then when even just a litte throttle input it would stutter and pop real bad. Replaced opti with MSD opti and it was good.
Or is it popping at even just idle??
I had my car running mostly fine at idle, then when even just a litte throttle input it would stutter and pop real bad. Replaced opti with MSD opti and it was good.
Or is it popping at even just idle??
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Originally Posted by camar0corey
Is the igniton sparking on all 8 cylinders??
I had my car running mostly fine at idle, then when even just a litte throttle input it would stutter and pop real bad. Replaced opti with MSD opti and it was good.
Or is it popping at even just idle??
I had my car running mostly fine at idle, then when even just a litte throttle input it would stutter and pop real bad. Replaced opti with MSD opti and it was good.
Or is it popping at even just idle??
For one thing, it would not run with the spark at 40 degrees ATDC. Some cheaper, and most laptop based, scan software shows the spark advance as minus on many OBD2 cars. Ignore the minus sign, it's just your scan software. One sofware revision I had in my Tech2 did the same thing with the '97 LT1, but not the '96. That was some time back, they all display correctly now. Last I heard, Autotap still displayed the OBD2 LT1 spark advance like that.
Good luck, Ed
Good luck, Ed
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Ok, well both computers are out of 97 OBD2 cars both birds too, the other computer shows the exact numbers just about except positive. I started it by accident without the MAF hooked up and it ran fine, kinda rich since it was running from Speed Density, but didnt pop at all, tried switching to someone elses MAF and my friends computer and it runs fine, with my computer it pops again, any more ideas?
