Changing VTEC Engagement RPM
#1
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Changing VTEC Engagement RPM
I'm thinking bout getting a VAFC II, I'm wondering if lowering VTEC engagement from 6800 to like 5500 will make a decent diff. Decent being at least .2 secs on quarter. I'm not really looking to improve drag speed but rather get lil more oomf from the motor.
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vtec engagement is around 6000rpm....but it also depends on airflow/throttle position/atlitute....... lowering the vtec is basically to even out the power curve.... so instead of having a slight dip in power while it transitions from low cam to high cam.... the transition is smoothed out.... people have gained around 5 to 10rwhp with the vafc tuned...
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yeah i have the black one.. it's brand new. never used, never opened, still in original package.... and umm on tuning... there's no baseline.. you can either take it to a dyno and get it tuned... or you can test and tune it yourself....
ps.. sent you a pm on the price....
ps.. sent you a pm on the price....
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#9
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Also in response to the original question, lowering the VTEC engagement point shouldn't gain anything for your 1/4 mile time, because if you are actually trying for a fast 1/4 mile time, you should never be below 6000 RPM anyway. If you gain any time in the 1/4 by using the VAFC, it will be from leaning out the fuel mixture which will give you a bit more power (most noticeable above 8300 RPMs on the pre-04 models).
However, for non-1/4 mile driving, I think you can gain some power between ~5400-6000 RPMs by lowering the VTEC engagement point to 5400. I've found this helpful at autocrosses and track events, because I don't feel the need to downshift if I drop down to the 5500 RPM range in a corner.
Here's an example of the improvements made by tuning the VAFC on my car:
However, for non-1/4 mile driving, I think you can gain some power between ~5400-6000 RPMs by lowering the VTEC engagement point to 5400. I've found this helpful at autocrosses and track events, because I don't feel the need to downshift if I drop down to the 5500 RPM range in a corner.
Here's an example of the improvements made by tuning the VAFC on my car: