Timing question
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Honda-Tech Member
Joined: Oct 2006
Posts: 347
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From: Tulsa, OK
Timing question
Hello guys, I figured this forum would be the right place for this as it deals with tuning.
I know it is hard to answer with the information available, but I would like to know if I should head back to get a retune or not.
My old tune was a jackson racing supercharger on an LS motor. stock blower setup. Fuel was tuned to around 11.5 AFR on 91 octane. At full throttle near redline, datalogs show my timing being 42 degrees or so.
My new tune comes with an LHT manifold/intercooler to lower heatsoak and a 2-3psi stepper pulley. AFR was tuned to 12.5 on 91 octane. When datalogging at full throttle near redline, timing stays around 30 degrees.
Same fuel octane, same spark plugs.
Is this about correct? car runs cooler and leaner so you can subtract timing? The reason that I am asking is because I actually made LESS peak power on the new dyno tune than on the old one. the old dyno was a dynojet, the new is a dynapack. the old one is halfway across the country so I can't really go there to double-check. I made 165 peak on the old one, 145 peak on the new one. The old tuner spent some time playing with timing, checking plugs after every run. the new tuner checked his timing curve, checked the plugs once, but did not play with timing at all.
I had a small amount of belt slip up near redline on the dyno, and my muffler went down from 2.5 to 2.25 between tunes. that's about all the changes in the setup between the two times.
I know it is hard to answer with the information available, but I would like to know if I should head back to get a retune or not.
My old tune was a jackson racing supercharger on an LS motor. stock blower setup. Fuel was tuned to around 11.5 AFR on 91 octane. At full throttle near redline, datalogs show my timing being 42 degrees or so.
My new tune comes with an LHT manifold/intercooler to lower heatsoak and a 2-3psi stepper pulley. AFR was tuned to 12.5 on 91 octane. When datalogging at full throttle near redline, timing stays around 30 degrees.
Same fuel octane, same spark plugs.
Is this about correct? car runs cooler and leaner so you can subtract timing? The reason that I am asking is because I actually made LESS peak power on the new dyno tune than on the old one. the old dyno was a dynojet, the new is a dynapack. the old one is halfway across the country so I can't really go there to double-check. I made 165 peak on the old one, 145 peak on the new one. The old tuner spent some time playing with timing, checking plugs after every run. the new tuner checked his timing curve, checked the plugs once, but did not play with timing at all.
I had a small amount of belt slip up near redline on the dyno, and my muffler went down from 2.5 to 2.25 between tunes. that's about all the changes in the setup between the two times.
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Joined: May 2007
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Re: Timing question (spets)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by spets »</TD></TR><TR><TD CLASS="quote"> the old dyno was a dynojet, the new is a dynapack. . </TD></TR></TABLE>
You can't compare different dyno manufacturer readings against each other. Hell, even 2 Dynojets will have different readings with the same car.
By cooling the intake charge, you got more timing leeway. Hotter air has more of a tendency to detonate, hence the timing decrease by cooling it off. I think you may have negated some of the intercooler by increasing the boost pressure, though.
You can't compare different dyno manufacturer readings against each other. Hell, even 2 Dynojets will have different readings with the same car.
By cooling the intake charge, you got more timing leeway. Hotter air has more of a tendency to detonate, hence the timing decrease by cooling it off. I think you may have negated some of the intercooler by increasing the boost pressure, though.
Thread Starter
Honda-Tech Member
Joined: Oct 2006
Posts: 347
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From: Tulsa, OK
Re: Timing question (King V)
Those numbers that I gave before were actual timing. the table timing is:
33 without the intercooler
23 with the intercooler.
does this seem about right? too high? too low? regular B18B series motor. stock internals.
33 without the intercooler
23 with the intercooler.
does this seem about right? too high? too low? regular B18B series motor. stock internals.
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