bee20egsix

A B20vtec. Replaced b16a1 intake manifold/ TB setup and replaced w/ the above. The old fuel rail didn't fit b/c of fuel regulator location. So I installed a new AEM one w/ ITR fuel rail. Fuel pressure is set @ 45 psi w/ vacuum line unattached. I am running it on the low end of the spec requirements trying to make up for the 12MPG +/- I lost. I had it @ 52 psi w/ vacuum line unattached but MPG was REAL bad, thought I needed more fuel to match up with the increased air flow, plus its a 2.0L. Stock injectors at the moment 240cc. I have some RC 310's and a V-AFC that I plan on installing soon but won't my MPG be even worse...?

I can't help but feel that the car is a little slower and idles a little rougher too. What gives..? It was pulling harder @ VTEC before and now I feel it, just engagement is not as hard.

I have a mugen spec P28. I am beginning to wonder, will the ECU increase the fuel to match the air to a certain degree (self-compensate), regardless of the fuel pressure....?

BTW I was meticulous reattaching all vacuum lines and sensors, in original positions. Also allowed Ecu to reset and recalibrate to new parameters.

To all the NOOBIE haters, I realize that with all the mods I have I probably shouldn't expect the greatest MPG's to begin with but I guess if that was my primary concern then I wouldn't have gone with a CR/Vtec would I..? I am just beginning to wonder if it's not a symptom of a bigger problem or something I did incorrectly.....

Maybe I was just spoiled cuz it felt hella fast when I put the `00 J-spec ITR tranny and the mugen ecu and still got 35 MPG...! Now its @ 22 MPG +/-.......

Does that drastic of a change sound fishy to anyone...Just wondering whats a realistic expectation....

One other thing. The old TB had 2 holes for the air to bypass when the butterfly was closed. The Spoon TB only has 1. I was wondering if this could be resposible for the rough idle, since maybe the fact that its a 2.0L it may need more air to idle ( right now it wants to idle low @ 500rpm +/-)

A ....to anyone who could offer some insight.

Thanks In Advance.
Matt

93SSPHatch

I have heard that the Mugen program just eats gas! Get that VAFC installed, and go have it tuned with a widebody 02 sensor. You can probably lean out the fuel a little bit on the idle side, and beef it up on the upper RPM range.

I have not actually experiecned a mugen program, but I have several friends who are using one, and they say it runs way rich.

Good luck.

bee20egsix

I had the Mugen ECU in there before I swapped IM & TB though , & MPG was great. What gives..?