dyno help ?????
12-24-2004, 05:41 PM
#11
Originally Posted by h777
sorry guys i dont know why it's not working........but can any of you guys tell me what could make the hp drop at 4400rpm and went from 12.2 to 9.75 a/f....could this be from knock retard?????
hp at 4400rpm was 396 then dropped to 341hp real quick then gradually went up to 367hp at 5400rpm
hp at 4400rpm was 396 then dropped to 341hp real quick then gradually went up to 367hp at 5400rpm
Philip S.
12-24-2004, 05:43 PM
#12
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Could you have started to get knock and then the PCM take a bunch of timing out? With the reduction in timing and no reduction in fuel I would think you'd go rich like that but I really don't know. Just a stab in the dark on a PCM we know nothing about. Another thing was how was your bottle pressure? Was the bottle full and pressure high through the whole run? If you drop too much bottle pressure I could totally see you going pig rich since your're losing nitrous and the fuel remains the same.
12-24-2004, 06:49 PM
#13
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Originally Posted by F8L Z71
Could you have started to get knock and then the PCM take a bunch of timing out? With the reduction in timing and no reduction in fuel I would think you'd go rich like that but I really don't know. Just a stab in the dark on a PCM we know nothing about. Another thing was how was your bottle pressure? Was the bottle full and pressure high through the whole run? If you drop too much bottle pressure I could totally see you going pig rich since your're losing nitrous and the fuel remains the same.
i turned on the spray at 3500 to 3700rpm the bottle pressure was 1050 when started then 1000psi after the dyno run.....bottle had 4 to 5 pounds left in it.....i'm thinking it might of been the low octane 92 gas but i could be wrong this was only a 100hp shot....have you guys ever heard of anything like this???? dropping hp real quick
12-24-2004, 08:32 PM
#14
Originally Posted by F8L Z71
With the reduction in timing and no reduction in fuel I would think you'd go rich like that but I really don't know.
Philip S.
12-24-2004, 08:38 PM
#15
Originally Posted by h777
i turned on the spray at 3500 to 3700rpm the bottle pressure was 1050 when started then 1000psi after the dyno run.....bottle had 4 to 5 pounds left in it.....i'm thinking it might of been the low octane 92 gas but i could be wrong this was only a 100hp shot....have you guys ever heard of anything like this???? dropping hp real quick
Philip S.
12-24-2004, 08:38 PM
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Originally Posted by BigBlockChev572
Timing and fuel supply are not related.
Philip S.
Philip S.
12-24-2004, 08:41 PM
#17
Originally Posted by F8L Z71
Thanks for the heads up. I tend to get mixed up with real computer systems and old hack job FMU setups on blower cars. LOL
Philip S.
12-24-2004, 08:52 PM
#18
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Do you not have custom tuning? If not your stock shift points and rev limiter is hurting you alot! Also you need to put some valve springs in to raise the rev limiter safely! I think the stock tune has alot to do with it! Am I way off guys?
12-24-2004, 09:23 PM
#19
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Originally Posted by BigBlockChev572
It shouldn't be the octane of your gas, but I'm not sure. Most people run around 92-93 octane on 100 shots. KR would have reacted much quicker than the 900 RPM window in which the HP started to drop. It's probably a dumb question, but did you lock your trans. is a certain gear? No up shifting?
Philip S.
Philip S.
12-24-2004, 09:26 PM
#20
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Originally Posted by TigerFan187
Do you not have custom tuning? If not your stock shift points and rev limiter is hurting you alot! Also you need to put some valve springs in to raise the rev limiter safely! I think the stock tune has alot to do with it! Am I way off guys?
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