Does lowering your vtec point to say 5500 actually increase power? Or does is just make it come sooner. I have a 04 and i notice that i am always out of vtec when i drop it unlike in my 00 when i was always in vtec when i dropped it.

I am thinking of getting a vafc and lowering it to 5500 so it would kick in sooner and i wouldn't have to wait. Also could tune the Air/Fuel.

Will this actually make the car go faster or give me anymore power?

 

Properly tuned the vafc is an awesome modification, and it will give you more power, but I don't think it'll be much by just making the vtec kick in earlier. Maybe with bolt ons and proper tuning on the dyno, I would expect gaoins of 10-to 15 hp. My friend did that with his gs-r( put vtec point to 5000) and he kept getting the check engine light, the car wouldn't rev past 5500. He he has header, intake and exhaust, but when he got it tuned you could really feel the difference in his cars performence. It hauls asss. Very good mod to have tuned well. But I believe his gas mileage went down as well. Since vtec kicks in earlier, the engine needs more fuel to compensate for more air. I will be getting my vafc soon as well, hopefully.

 

The AFR curve in the '04 is probably closer to optimum than it was on the '00-'01 so a V-AFC may not gain you much power like it did on the '00-'01. Lowering the VTEC engagement point is going to give you a little more power earlier, but you have to find the right engagement point through trial and error. I think the best way to find it is to lower the VTEC engagement 100 RPMs at a time on the street (with all fuel correction set to 0's) until you no longer feel the VTEC kick. Then you need to go to a dyno with a WBO2 to tune it. With tuning, you may be able to lower VTEC engagement by another 100 or so RPMs.