Possible fuel problems.
Thread Starter
Burning Brakes
Joined: Oct 2008
Posts: 1,109
Likes: 0
From: Morgantown WV
Possible fuel problems.
Car is a Z06 with a Novi 1500 on 4lbs and meth. I just got it on the road this week and did a couple 3rd gear pulls. 1st and 2nd pull fine throught the RPM range but in 3rd gear it falls on its face hard @ 6K. I wasnt looking at the AFR's so I did one more pulll to make sure they were good and the meth was spraying. Had a green light for the meth and AFR's were around 13.5. YIKES!
The car has an MSD regulator, 60# injectors, and I believe a KB BAP. My best way to troubleshoot is to add a fuel pressure gauge right? Anyone experienced something similar? I read the other active thread regarding pressure but I havent read anyone describing my issue. Why would it not fall on its face in 1st-2nd or maybe I am just not noticing it as much? I am a noob to most of this so any advice is appreciated.
The car has an MSD regulator, 60# injectors, and I believe a KB BAP. My best way to troubleshoot is to add a fuel pressure gauge right? Anyone experienced something similar? I read the other active thread regarding pressure but I havent read anyone describing my issue. Why would it not fall on its face in 1st-2nd or maybe I am just not noticing it as much? I am a noob to most of this so any advice is appreciated.
Last edited by D-Rod; Jul 20, 2012 at 06:03 PM.
Pro
Joined: Feb 2003
Posts: 745
Likes: 136
From: Detroit MI
Yes, start by verifying fuel pressure all the way up to redline under boost, preferably in 4th gear since this will be the most taxing on the system. (Unless you find yourself pulling 5th gear for standing mile or longer races)
BTW, who needs meth with only 4psi? Sheesh. Your fuel system should be able to handle this without the methanol as long as nothing's broken.
BTW, who needs meth with only 4psi? Sheesh. Your fuel system should be able to handle this without the methanol as long as nothing's broken.
Thread Starter
Burning Brakes
Joined: Oct 2008
Posts: 1,109
Likes: 0
From: Morgantown WV
BTW- the DIC said I was averaging 40mpg on a 30 mile interstate trip. I pulled a couple plugs last night......
http://www.youtube.com/watch?v=g_I64oMxcZo&feature=plcp
http://www.youtube.com/watch?v=g_I64oMxcZo&feature=plcp
Instructor
Joined: Jan 2011
Posts: 214
Likes: 0
From: Des Moines, Iowa
Man, seems like everyone is having fuel pressure issues lately. I agree that's the first thing to check, get a fuel pressure gauge on there.
However, I think a Z06 pump and BAP should easily keep up with 4psi. I'm running the same pump and BAP on 5.5psi and E85 without pressure drop.
While 13:1 AFR is pretty lean, I wouldn't think this is lean enough to make it fall on its face. Maybe something else is contributing as well.
However, I think a Z06 pump and BAP should easily keep up with 4psi. I'm running the same pump and BAP on 5.5psi and E85 without pressure drop.
While 13:1 AFR is pretty lean, I wouldn't think this is lean enough to make it fall on its face. Maybe something else is contributing as well.
Pro
Joined: Feb 2003
Posts: 745
Likes: 136
From: Detroit MI
Nope. It's not. Try again by comparing miles traveled (odometer) vs gallons purchased at the pump and you'll see something completely different. If you have 60#/hr injectors in there, the tune has some amount of scaling in it to make it work and this results in a skewed calculation for MPG.
Racer
Joined: Jul 2011
Posts: 417
Likes: 0
Nope. It's not. Try again by comparing miles traveled (odometer) vs gallons purchased at the pump and you'll see something completely different. If you have 60#/hr injectors in there, the tune has some amount of scaling in it to make it work and this results in a skewed calculation for MPG.
