wicked_95z

iTrader: (8)

I went from a 3.7 pulley on my procharger to a 3.4 with a FMIC. I have only been cruising around with it, no WOT blasts, and I pulled my plugs today and they were white as the day I put them in. I always understood that you want your plugs tan in color and maybe a little darker considering FI engines are usually run rich. I was curious if it was normal to have this much of a change in A/F from the mods I did. I had the car dyno tuned with the 3.7 pulley and the twins so Im sure the a/f was okay before hand. Am I increasing the incoming air that much? My fuel pressure is 50 psi at static. Should I bump it up to 55 or 60 until I can get it retuned?? Thanks

BIG BAD BLACKSS

iTrader: (4)

You added more air, so you need to program it for more fuel too.

wicked_95z

iTrader: (8)

Any idea of a percentage of increase

BIG BAD BLACKSS

iTrader: (4)

Get it dyno tuned, or if you can find someone that nows what theya re doing use a wideband and do alotta data logging and trial and error. Hopefully nothing blows up!

wicked_95z

iTrader: (8)

Ohhh I dont think I want to leave it up to trial and error. Would be kind of an expensive oopsy. Especially giving my previous track record at tuning

DeltaT

iTrader: (5)

That's not a huge change - I suspect only 1-2# of boost more. Are you running a boost referenced regulator? Figure it's about a 8% change, so if you are not boost referenced, I'd start by jacking up the FP from 50 to 55 (a 10% change) just to be safe. Check the plugs again. I can't believe it would need a complete new dyno tune, if it was tuned correctly before the pulley change.

Jim

Blown SS

iTrader: (13)

I'm sure he's picked up more than 1-2 #'s . I would guess 1-2 with the FMIC alone and another 2-3 with the pulley

EPP

iTrader: (22)

I wouldn't chance it, too expensive of an outcome may result. I'd get it retuned right away. Bob

STALL UP

iTrader: (2)

procharger told me that a 1/10 of a pulley change = 1psi on a 346 with a p1sc.

DeltaT

iTrader: (5)

I guess I read it wrong - I didn't pick up that he added the FMIC as well as the pulley change. I agree that that changes the equation and he needs a new tune.

Jim

wicked_95z

iTrader: (8)

And that is what I've been told by a buddy of mine as well. I would just like to get it rich enough on cruise to drive around. As far as WOT, I can always crank up the gain of the meth controller