PT88 turbo LS6 wont pull past 5k, w/dyno graph
#44
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I hope that it is a grounding problem so that it would be a cheap simple fix....I have a feeling its not though. If it was I feel like it would be more sporadic and/or if there was a ground bad it wouldn't make it to 5k rpm. If it was a intermittent ground problem it would probably fix it self the first couple times it arced and made a good connection.
#45
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yes non resister, how much boost? i would say .20-.25 should be fine...... yes i have seen this on non-projected stuff its even worse on nitrous cars i have seen.... i know alot of people here are going to tell me i am wrong blah blah..... i just know what i have seen on my dyno and when i swap plugs the problem goes away....
#46
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yes non resister, how much boost? i would say .20-.25 should be fine...... yes i have seen this on non-projected stuff its even worse on nitrous cars i have seen.... i know alot of people here are going to tell me i am wrong blah blah..... i just know what i have seen on my dyno and when i swap plugs the problem goes away....
My current set up is pretty close to the one in questions, 80mm, 6.0l manifolds, 317 heads, TH400, 9", my short block is stock though. I am running TR7's without a problem.
Does the car sound like it is missing? or is it still smooth and just doesn't pull any more RPM? If its blow out it should show a misfire and the knock sensors should pick it up. That would be easily seen on a log with HPTuners.....if there is no sign of knock I would lean more towards the tranny....if its knocking and pulling timing then the plugs could be likely.
#49
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I wouldn't say your wrong just that I have never seen it. I ran TR6 plugs in my vette with 150 shot with no problem.
My current set up is pretty close to the one in questions, 80mm, 6.0l manifolds, 317 heads, TH400, 9", my short block is stock though. I am running TR7's without a problem.
Does the car sound like it is missing? or is it still smooth and just doesn't pull any more RPM? If its blow out it should show a misfire and the knock sensors should pick it up. That would be easily seen on a log with HPTuners.....if there is no sign of knock I would lean more towards the tranny....if its knocking and pulling timing then the plugs could be likely.
My current set up is pretty close to the one in questions, 80mm, 6.0l manifolds, 317 heads, TH400, 9", my short block is stock though. I am running TR7's without a problem.
Does the car sound like it is missing? or is it still smooth and just doesn't pull any more RPM? If its blow out it should show a misfire and the knock sensors should pick it up. That would be easily seen on a log with HPTuners.....if there is no sign of knock I would lean more towards the tranny....if its knocking and pulling timing then the plugs could be likely.
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I had 2 bad plug wires that misfired on the dyno, no codes and no KR. Rpm wouldn't climb past 5900, couldn't hear the misfire, just ran flat.
I think it's in the ignition somewhere, boost and rpm will expose all weak pieces in the ignition.
I think it's in the ignition somewhere, boost and rpm will expose all weak pieces in the ignition.
#57
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I don't trust plugs or wires when doing a visual inspection, they can carbon track or have other issues that aren't worth the headache. If I have a misfire I always throw plugs and wires on the car first.
#58
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I agree 100% with a ryne@cms I too have seen it on my dyno numerous times. I would seriouusly put a set of tr6's in and take it for another pull and see what it does. It is a LOT cheaper and easier then pulling the heads or transmission.
#59
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IF it is a lifter issue, could the boost creep also be an indicator seeing how the valves wouldn't be opening fully as well as killing the rpm's? Sorry if that sounds odd. I'm no expert here but very curious what the issue is after reading through all of this. Good Luck with it!!