I have a 99 ex with cam pulley valves, springs, bigger injectors, vafc2, cold air intake, header back exhaust. I was just wondering if anybody knew some basic settings I could star with for tuning the vafc. I got it pretty close but it still isn't right my gas mileage is pretty bad.

 

what kind of mileage are u gettin ? ----honda tweeks their motors for good mileage so the more mods u do the less mpg you will get ---but in sure u got more plenty of power----but i would think the big injectors have something to do with it

 

start by taking out 1-2 percent of the fuel. but youre not going to make any power with that thing without a dyno or at least a wideband O2.

 

exactly... You will need a wideband o2 sensor... you can buy one for around $300 or get a few Dyno pulls in for about $50 a pop.

Run you rcar and see what the a/f ratio is at... Ideal when you are at wide open throttle is about 12.5:1. So it sounds like you are running rich (too much fuel). The reading should be lower than 12-13 ish (probably something like 10-11:1) If this is the case then take away fuel (lean it out). Keep experimenting until you are where you want to be.

If you buy a wideband o2 sensor then you can do all the test you want... on the road.

most cases:

Peak HP is reached at 12:5:1 a/f ratio
Peak torque is reached at 13.8:1 a/f ratio