My friend has a Apexi VAFC on his single cam and swears by it. I was just curious as to anybody elses opinion on these. Is it really worth it for a SOHC? What are the biggest gains one could expect if any? I was considering picking up either the Field or the Apexi if i would see any difference considering im stayin SOHC.
Any help would be greatly appreciated. Thnx.

 

It's good for tuning if you have an aftermarket cam, but you won't get a whole lot of power if that's what you're asking. You can tune fuel a little bit and set the VTEC crossover poing, and have a cool looking display. All this however should be dyno tuned. Most people get a vafc and set the thing to crossover as low as they can, which actually hurts performance. Most people with an aftermarket cam/springs/retainers actually set the vtec xover higher than stock to compensate for the new powerband.

 

so for lightly modded SOHC vtec motors its not really going to have any substantial impact on performance? I am more than likely going to be getting one anyway for future modding or motor swapping. If you dubster99 or anyone else could recommend some tuning specs or settings for a lightly modded D16z6 with a APEXi VAFC it would be greatly appreciated.

 

Like he said, it should be dyno tuned. That said, most people running n/a see gains from cutting fuel 4-5% under VTEC, since the stock map is slightly rich.

 

yeah another thing that people think is that they can set the VTEC lower, which will gain more power...but what they don't know is that the AFC merely tells the solenoid to engage earlier--- but doesn't tell the ecu that vtec is engaging earlier. So this results in horrid performance because the vtec lobe requires alot more fuel (obviously) than the non-vtec lobe-- and the ecu doesn't give the increase in fuel until the stock rpm that vtec should engage. Also, afc's are very very helpful in tuning turbo'd cars.

 

The AFC has VTEC UNMATCH settings that are supposed to account for when the ECM thinks the car is not in VTEC when it actually is, and when the ECM thinks the engine is in VTEC when it's actually not. These settings should, of course, be tuned on a dyno.

 

hmmm i guess ill have to take it to a local dyno shop

 

VTEC makes the valves stay open longer....setting it too low will drastically hurt performance.

 

thanks for the advice guys!! i guess i will have to see where i can get it tuned properly.. ill let my fingers do the walkin =)