Help any ideas?
Help any ideas? A few years ago after I built my 99 FRC I took it to Speed Inc. to be tuned. Result= 415 rwhp and an afr of 12.5 across the board. Today with only change being a ti Z06 cat back (now) vs a Borla(then) 350 rwhp with an afr of 15 !!!!!!! I know the differences between dynos (dynojet vs mustang) and the like but what could cause the afr? When I say no other changes the car still has the same plugs in it! I figured with the old plugs and more restrictive exhaust (maybe) it would be richer not majorly lean!!!! No ses lights or anything car runs fine I just thought something might be up because I could swear I heard some detonation but everyone said I was crazy, guess not. Thanks guys.
Staging Lane
Joined: Jun 2007
Posts: 95
Likes: 0
From: Tuscon AZ
lol...thats pretty strange. You're right, it should have went richer with the different exhaust.
The only thing I can think of is the altitude of the dyno...did you dyno in Colorado the 1st time and Miami the 2nd time??? lol...jk
The only thing I can think of is the altitude of the dyno...did you dyno in Colorado the 1st time and Miami the 2nd time??? lol...jk
Fuel pump or a fuel issue of some sort.
I had the same thing happen; should have been 340 HP, Dynoed at 270 HP and AFR was 15.1. I was logging fuel pressure and found the pressure dropped to 35 PSI and did not recover.
Dyno again and watch your fuel pressure.
I had the same thing happen; should have been 340 HP, Dynoed at 270 HP and AFR was 15.1. I was logging fuel pressure and found the pressure dropped to 35 PSI and did not recover.
Dyno again and watch your fuel pressure.
Agreed....check your fuel pressure...something is way wrong there.....dont get on it either...dont want to hurt it! Do any tuning on a mustang dyno....A lot better to have a load on the car than just the free spinning well...real street type testing for a street car
A little update. Checked the fuel pressure 58-60 and no drop during a neutral rev. Checked with a scanner and no codes were found. I took the MAF off and there was a film of something on it? I have a dry blackwing filter don't know what could be on the MAF? I cleaned it so we will see.
