Just bought the 12psi pulley from ATI
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From: toronto
Just bought the 12psi pulley from ATI I just bought the 12 psi pulley for my truck
I'm currently seeing 9 psi with the stock pulley then sent me. I was wondering how much timing i could get away with on this pulley
we had the 9 psi up to 23degree and had no knock
but heard some pinging /detonation back it down 4 degrees and it was fine
I've got lots of fuel with my larger injectors 13/4 " primaries on the headers I'm running
i see people running 10psi on the stock compression of the 5.7l ls1 i've got a 5.3l with a compression of 9:5:1
what should i consider ?
thanks a bunch
Jim
<small>[ October 12, 2002, 10:39 AM: Message edited by: GMC SKI ]</small>
I'm currently seeing 9 psi with the stock pulley then sent me. I was wondering how much timing i could get away with on this pulley
we had the 9 psi up to 23degree and had no knock
but heard some pinging /detonation back it down 4 degrees and it was fine
I've got lots of fuel with my larger injectors 13/4 " primaries on the headers I'm running
i see people running 10psi on the stock compression of the 5.7l ls1 i've got a 5.3l with a compression of 9:5:1
what should i consider ?
thanks a bunch
Jim
<small>[ October 12, 2002, 10:39 AM: Message edited by: GMC SKI ]</small>
Re: Just bought the 12psi pulley from ATI 9.5 compression PLUS anything over 10 psi is seriously pushing the limits of pump gas... with good tuning (ie: 18 degress of timing, 13:1 a/f ratio) you could MAYBE run 12 psi reliably...
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Re: Just bought the 12psi pulley from ATI </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by masterdill:
<strong>9.5 compression PLUS anything over 10 psi is seriously pushing the limits of pump gas... with good tuning (ie: 18 degress of timing, 13:1 a/f ratio) you could MAYBE run 12 psi reliably...</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">I'd recomend shooting for a 12:1 A/F and timing well, its trial and error with that, personally any amount of boost you have to retard timing below 20 degrees, you should stop, at that point you are trading power in boost for timing.(it may broaden your power band a little though) basically I would do two tunes tune 1 would be pump gas, and a lower boost level, and tune 2 would be race gas, higher boost and timing.
<strong>9.5 compression PLUS anything over 10 psi is seriously pushing the limits of pump gas... with good tuning (ie: 18 degress of timing, 13:1 a/f ratio) you could MAYBE run 12 psi reliably...</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">I'd recomend shooting for a 12:1 A/F and timing well, its trial and error with that, personally any amount of boost you have to retard timing below 20 degrees, you should stop, at that point you are trading power in boost for timing.(it may broaden your power band a little though) basically I would do two tunes tune 1 would be pump gas, and a lower boost level, and tune 2 would be race gas, higher boost and timing.
