It's a 03 ap1 stock comptech kit with a aftermarket exhaust making 304whp, but I'm running lean 13.1 A/F between about 6300 to 7500 rpm. We turned the FPR clockwise 5 times for more fuel and still no major change in A/F.

I wanna hit the tracks soon, but worry about the high A/F. I've heard from friends that the numbers are safe on the streets but I don't wanna take any chances on the track. Plus my tuner is freaking out, he doesn't think its safe period.

At this time I would like to stay away from EMS and I've read good and bad about VAFC.
How about those AEM FPR? I'm just looking for a inexpensive solution at this point.
I hope you guys can provide me with some insight on what to do, Thanks in advance.

FYI the car made 305 with the stock exhaust but leaning out in the same area also.

DYNO numbers


FPR turned 5 times, I don't think I can go any lower.

 

sometimes if you go in too far it actually starts to lower fuel. Your numbers look fine. The car is only making like a few pounds of boost when its in the 13's. Pretty much NA at 6000

 

I wouldn't trust it, a buddy of mine blew an engine for running too lean with his SC along with a few others on these forums.

Get a VAFC / emanage to make her safe before you go nuts with it. I rather drive it nice for a week, get a REAL tune, and not blow a 5,000 dollar engine.

 

i would get a piggyback like emanage ultimate or standalone like EMS/k pro and get it tuned properly!

 

Any major difference between a NEO vs. a regular vafc ver. 2 or 1?

Since I'm pretty stock and don't for see any major mods, I want stay away from standalone. I heard that the ECU have to be reset often with the vafc?

 

I ran the same AFR's non aftercooled with 8.5 lbs of boost for over a year here in socal with no problems.

My FPR bolt was lower than yours also.

 

standalone is not that big of a deal...... aem ems here and would never go back to any vafc piggy back. my hatch had piggy back crap with fmu on it and was a nightmare.

sell your fmu, buy a ems, grab some injectors, and get it tuned.

 

304 with a stock kit? maaaaaaan im making 260whp/160tq on a 7psi pulley and aftercooler w/ bigger radiator and header/tp/exhaust LOL.

 

what fuel pump are you using?
if it is a walbro 255 is it the hp

And are you sure - we have had several that said 255 - but not the hp version - big difference in gear rotors inside them

How old is your fuel pump - seen severasl only last 2 or so years especially with a fpr hooked to them.

you could also try upgrading power wire to fuel pump, voltage loss thru the factory wiring is there.

how about fuel filter? could it need to be changed - restricing flow, you would only see it at higher rpms when you are using more fuel.

 

The Vafc will only cut fuel on our car, if you try and add fuel with a vafc the car will freak out so that isn't an option.

I would like to hear what people think as well. I'm starting to think this is the typical for all Comptec kits, but not everyone has a wide band like myself or gets sniffed at the tuner to see whats going on.

My fpr is ajusted almost flush with the lock nut, about two more turns then yours. Works out to being set up to run 60psi at idle and about 90ish at WOT. In this state it runs 12:1 at 9000 which is good, but it still runs 13:1 from about 6-8k like yours. Below vtec it would run 10:5- 11:1 range if it wern't for my vafc cutting fuel in this rpm. This set up works pretty good, but not ideally what I was expecting to have to do.

Anyone else experience a similuer thing and know how to improve it? I don't like 13:1 either, but I think its pretty safe at 3-4 psi I hope. I only have about 3k miles on my car since SC and its taken me this long to figure out how to set up my current A/F situation with what I have.

The stock Comptech fpr settings needed to run max without a vafc to lean out the bottom end would be crazy. Makes me think there is something not right as well. I guess for more then just me.