Do I really need the FMU??

Stang_Crazy · 08-17-2002, 08:16 PM

I need to buy injectors for the Novi but I was thinking of buying bigger injectors and scraping the FMU. Would 30# be enough without the FMU? or should I go with 36#? Also, I'm going to be using a 255 in-tank fuel pump. Thanks for the help!

speedytang · 08-17-2002, 08:58 PM

If you are at the 8lb of boost level 36lb will work but if you have no way of adjusting fuel levels for idle and wide open throttle leave the FMU to have a good idle and a rich top end. No damage that way.

Stang_Crazy · 08-17-2002, 09:10 PM

Well, the blower isn't on just yet. I'm waiting until winter, or until I run a 13.9 to put it on. For now, I'm trying to get all the parts together so I won't need to get anything while I'm in the middle of the install. I won't be at 8# with the basic setup but I plan on swapping crank pulleys so that should put me close to 8#.

exgmguy · 08-18-2002, 04:34 PM

Go with no FMU (FCU Paxton calls it) and get 36 lb injectors. Also have your meter "supercharger" calibrated when you do the injectors.

FMU's do tend to run rich up top, and too rich is slow. I have been through the whole Novi 1000 thing, so any questions I can probably answer.

Stang_Crazy · 08-18-2002, 10:15 PM

What is the difference between having the meter calibrated for 36#'ers and "supercharger" calibrated?? Is there a difference?

RdRunnr · 08-18-2002, 10:31 PM

The SC calibrated meter runs 15% richer across the board. Haven't you guys ever run bleeder valves on your FMU's? With a bleeder valve the FMU will NOT run rich up top.

Hozer 88GTConv · 08-19-2002, 08:26 AM

Are you going to have a chip burned?
My setup (in progress right now) deletes the FMU in favor of a custom chip (Johnson Motorsports).
Also, at 8lbs wouldn't 42# injectors ensure proper fuel delivery and eliminate potential detonation.
I'm setting up a Vortech SQ at 8 lbs...

08-17-2002, 08:16 PM	#1
Stang_Crazy It's never clean enough! Join Date: Jan 1999 Location: Shaler, PA Posts: 1,542	Do I really need the FMU?? I need to buy injectors for the Novi but I was thinking of buying bigger injectors and scraping the FMU. Would 30# be enough without the FMU? or should I go with 36#? Also, I'm going to be using a 255 in-tank fuel pump. Thanks for the help! __________________ ~Dan 2001 SVT Lightning 89' GT : Taking up garage space and waiting for a buyer... Rice Hater's Club - Member #11

08-17-2002, 09:10 PM	#3
Stang_Crazy It's never clean enough! Join Date: Jan 1999 Location: Shaler, PA Posts: 1,542	Well, the blower isn't on just yet. I'm waiting until winter, or until I run a 13.9 to put it on. For now, I'm trying to get all the parts together so I won't need to get anything while I'm in the middle of the install. I won't be at 8# with the basic setup but I plan on swapping crank pulleys so that should put me close to 8#. __________________ ~Dan 2001 SVT Lightning 89' GT : Taking up garage space and waiting for a buyer... Rice Hater's Club - Member #11

08-18-2002, 04:34 PM	#4
exgmguy Registered Member Join Date: Feb 1999 Location: Utica, Michigan Posts: 2,631	Go with no FMU (FCU Paxton calls it) and get 36 lb injectors. Also have your meter "supercharger" calibrated when you do the injectors. FMU's do tend to run rich up top, and too rich is slow. I have been through the whole Novi 1000 thing, so any questions I can probably answer. __________________ 1988 Mustang GT stock bottom 302, C4 10.9 @ 128 with 8 psi of Novi 1000 boost!----STOLEN 1989 Mustang notchback Warmed up 306 with a Procharger.

08-18-2002, 10:15 PM	#5
Stang_Crazy It's never clean enough! Join Date: Jan 1999 Location: Shaler, PA Posts: 1,542	What is the difference between having the meter calibrated for 36#'ers and "supercharger" calibrated?? Is there a difference? __________________ ~Dan 2001 SVT Lightning 89' GT : Taking up garage space and waiting for a buyer... Rice Hater's Club - Member #11

08-18-2002, 10:31 PM	#6
RdRunnr Registered Member Join Date: Dec 1999 Location: Newark,DE Posts: 98	The SC calibrated meter runs 15% richer across the board. Haven't you guys ever run bleeder valves on your FMU's? With a bleeder valve the FMU will NOT run rich up top. __________________ Eric 1990 Mustang GT 10.46 @130.97 ClickClickracing Forums

08-17-2002, 08:58 PM	#2
speedytang Registered Member Join Date: Oct 1999 Location: Marengo, Ohio.USA Posts: 135	If you are at the 8lb of boost level 36lb will work but if you have no way of adjusting fuel levels for idle and wide open throttle leave the FMU to have a good idle and a rich top end. No damage that way.

08-19-2002, 08:26 AM	#7
Hozer 88GTConv Registered Member Join Date: Feb 2002 Location: Jacksonville, FL Posts: 706	Custom Chip? Are you going to have a chip burned? My setup (in progress right now) deletes the FMU in favor of a custom chip (Johnson Motorsports). Also, at 8lbs wouldn't 42# injectors ensure proper fuel delivery and eliminate potential detonation. I'm setting up a Vortech SQ at 8 lbs... __________________ 1988 GT Convertible 331 10:1 TW heads, GT-40 intake, MSD, TRW flattops, B Cam w/ 1.7's, MAC exhaust, 24's, 70 TB, 76 MAF, 3.73's, Pro 5.0, Koni's, Anderson PMS, Wideband 02, yatta, yatta... One week with new motor, two speeding tickets...joy