big stuff run screen shot? top end lay over!

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Sep 12, 2010 | 01:42 AM

van383

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big stuff run screen shot? top end lay over!

having some top end issues with no given obvious things on data log, tried to upload the file from bs3 but say invalid csv file? prob can not get much out of this screen shot.. but boost stays constent..timing..voltage..fuel pressure..tps.. and a/f all constent.. just as u see the rpm will fall and raise and fall again.. u feel it in car as well.. almost the feeling of spark blowout... i figure u ask this so br7efs at .026 gap it does it.. and a 7317-8 at .022 gap it did it.. the more u run the worst it gets thru night as well... have checked small things like grounds/fuel filter/ohm wires... also had the round truck coils (heard some have issues) im swapping to square type! my engine guys says lifters (reused stock ones) and wants to double check spring pressures... so ideas that i may not have thought of would help..

first shot is worst run of night
secong is a better run of night..

370cu
88 turbo
stock lifters
shift at 7-7300
hyd roller
317 heads known comp duals wrking when headsw where done
truck manifolds
60mm gate
5in dp
1.23 ex ar..

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big stuff run screen shot? top end lay over!-big-stuff-screen-shot.jpg

big stuff run screen shot? top end lay over!-big-stuff-screen-shot.jpg-2.jpg

Last edited by van383; Sep 12, 2010 at 03:41 AM.

Sep 12, 2010 | 08:17 AM

G Engines

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I cant help but notice your roil pressure is at 0 on your screen shot.

Sep 12, 2010 | 08:35 AM

98Z28CobraKiller

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Get rid of some lines and post it again. Also, put the marker on peak RPM right before falls off. .

I'd say to leave RPM, VBAT, Coolant, AFR, pct dc, TPS, boost.

So is the second log a normal one?

Last edited by 98Z28CobraKiller; Sep 12, 2010 at 08:41 AM.

Sep 12, 2010 | 08:45 AM

98Z28CobraKiller

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First log looks like ignition issues not sudden valve train instability all over the place. Is AFR staying pretty solid?

Sep 12, 2010 | 11:44 AM

camaroturbo

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when i had a big exh back psi prob my logs looked like the 1st one

Sep 12, 2010 | 12:28 PM

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X2..

Quote:

Originally Posted by camaroturbo

when i had a big exh back psi prob my logs looked like the 1st one

what I was wondering!

Sep 12, 2010 | 01:30 PM

van383

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Quote:

Originally Posted by 98Z28CobraKiller

First log looks like ignition issues not sudden valve train instability all over the place. Is AFR staying pretty solid?

ill try to do that with screen shot.. also afr are staying consistent thru thge run.. solid as u would ask.. and yes the one run is a normal run at start of night both runs same night...

so what and why would i be seeing issues with back pressure psi on time and not the next?