I installed an Apexi vafc 2 today on my AP1, and as while I was stuck in traffic today i set the vtec down to 4800K RPM(recommended from what I read here). I didn't really notice a big difference in performance until I hit factory vtec at about 6K RPM(40MPH -100MPH. Although I did miss my down shift into 2nd instead of 4th at about 60-65MPH(REDLINED). I was still on the HW and the car still seemed to perform well.

I don't hear anything unusual from my engine. Although, when I got off the HW I finally got to feel it in 1st gear. My car seems to start very slow from 0-20MPH. Once I hit about 3000RPM and up in 1st the car seems to be running fast and then vtec kicks off. Shifting to 2nd still good. Couldn't push it anymore than 80MPH(Radar detector went off). But 0-20 keeps feeling slow.

I just got my valves tuned and I don't think I blew my motor. If I did I would have noticed a performance difference when flooring my car in 2nd-4th gear right? Car still felt like it did before.

I took off the Apexi and going for a drive tomorrow to see if it is the Apexi. Do I need to dyno to tune the Apexi? I thought it would be a cheap alternative from getting a EMS.

 

what rpm were you at in 4th before shifting to 2nd?

 

If you were traveling 64 MPH when you downshifted to 2nd, that should be fine in an AP1 with stock gears and tire sizes, since that puts the RPMs right at the rev limiter.

The S2000 is tuned from the factory to pull a bunch of ignition timing below 3K RPMs at full load. I believe this is due to a strong resonance at that RPM from the stock intake. If you have an aftermarket intake with a resonance above 3K, then it's going to feel really weak below 3K.

You should not mess with the VAFC at all if you don't at least have a wideband O2 sensor and OBDII datalogger to tune with. If you just start playing around with different settings, you'll need a new motor soon.

 

Well my car issue was that I got to use to being in vtec going 100MPH. I just got use to the feel of vtec kicking in. Car ran fine when I took out the apex. I just thought my might have blown my engine. But I'll take your advice and keep the VAFC out for now. Thanks

 

Agree, i wouldnt mess with vtec on the fly. It took a wee while to set mine at the optimum point on the dyno.

Of course i dont have one anymore.

 

Dude ... if you're talking about VTEC at 100 MPH, you really need to take your car to someone that knows what they're doing.

 

I recently installed a VAFC2 and noticed now it cranks for an extra second or two before the engine turns over. Is this normal with a PnP harness

 

what are your mods? If you dont have a test pipe, you shouldnt need a vtec point any lower than ~5500. And I agree, it kind of sounds like your not too sure of what your doing / whats going on when you change things. If you really want to gain midrange from lowering vtec and get the most out of the VAFC, buy a test pipe and take it to a tuner You'll pick up some good midrange and if you have an AP1, some decent power up top as well