Hey guys, i just installed my aem wideband into my testpipe earlier today and went for a short 15 minute drive to collect the readings. First off its a CT SC, 4" pulley with FMIC, stock injectors, comptech esm, stock exhaust. Not sure about how much boost im seeing and FPR is not quite maxed out yet. While cruising around on the freeway and about 4-5k rpm it seems to jump around alot between 14-15.5:1 and when i go WOT about 6k rpm it richens up to about 11:1 then when vtec hits it jumps between 12-12.2:1 all the way to redline. So i have a couple questions:

- how are these numbers? should i lean it out or richen it up using the FPR?
- What numbers should i be seeing?
- I have a smaller pulley, im assuming a 3.8" maybe. Do i have enough headroom to use this pulley and keep everything else stock or is that pushing the limit on things like injectors and such?

Thanks a ton guys!

 

AFR sounds normal for the set up. The kit always runs richer under vtec then preferential, buts its necessary to run that safe 12-12.5 range above vtec. One easy and effective way to better perfect your AFR tune is to pick up a vafc and lean out the afr under vtec, lowering vtec is also available with the unit and will give you some more mid range power. Otherwise it sounds like your near the end of the fuel adjustment for your boost. Its possible you might have enough left for the 3.8" but couldn't say for sure without you just going out and testing it. You really don't want to go less then about 3 threads showing above the lock nut on the fpr post. One way to test if you have enough room is to see if you can get your current 12afr above vtec to hit 11.AFR. I have found generally on this set up, 1psi more of boost is worth about 1 point of AFR difference which is worth about 15whp. If you cant get your current set up to run flat 11 above vtec and without maxing out the fpr, then don't bother with the other pulley.

 

On my base SOS kit the RRFPR was set to 50psi static. It was hand written on the top of the reg by marker.

With the base fuel pressure of the kit i was around 12.2afr i goes leaner right after the vtec switch over and then back down to to around 12.9 - 13.1 to redline. Thats a little leaner than im use to

Im running a 3" header back. So i figured that i was running lean due to my exhaust. I bumped up static pressure to around 53-54psi i cant tell but just before 55psi mark on my fuel pressure gauge.

Im now it at 11.1 average before vtec and about 11.8-12.1afr after vtec switch over till about redline.

Set up.
aem 320lph fuel pump with 10ga re-wire with relay.
SOS RRFPR
Stock injectors

 

what type of fuel do you run. if on pump gas i would stay between 11.4.11.7 at WOT, my car on e85 cruises at 15.0-16.0 and 12.0-12.2 at WOT. you can be a little leaner on the lower end like 12.0-13.0 as you are getting into boost say 1-4lbs

 

I'm 11.5 on e85, but thats 20psi+

 

yea as long as you dont have knock ive seen cars go up to 12.5 on e85 with no issues. On my last evo i was running 28-29lbs on e85 and 12.0-12.2 afr's

 

Running just regular pump 91.

I only have about 2 threads showing on the FPR so i guess im pretty close to maxed out so forgot putting on the other pulley i suppose. So running in the mid 15s while cruising is ok? Thats about were i am crusing down the freeway at 70 or so. And the preferred numbers for WOT under vtec is in the 11s and above vtec till redline keep it in the mid 12s? Considering maybe picking up a VAFC to lean it out a bit under vtec as per s2000junky's reccommendation. How much gains are to be found by leaning it out in the middle and lowering vtec down to 5500? Thanks for the help guys

 

god i would kill for those numbers right now. im having severe issues with mine, same setup , same kit, fmic etc but with header and a 3 inch single. thinking i have a broken regulator. anyway your numbers are great

 

A decent chunk of midrange power can be gained by using a VAFC to lower your VTEC point, even if you just lower it to a modest 5,000 RPM (which is as low as I was willing to go just using a VAFC). I gained ~17 HP around that 5k-6k range, and it made my power curve much smoother and more gradual versus the VTEC spike of power. It was worth the purchase just to lower the VTEC point for me.

 

Also, I have a near identical setup to you. I run mid 14's at idle and cruise, and 11-12's under WOT from 3.5k to redline. Its a bit on the rich side but since we don't have any kind of good tuning capability, its the best we can do. Much better off running on the rich/safe side. I would keep it like it is until you decide to up the boost and get a good tuning solution like I did!