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mrflames
11-07-2005, 11:56 AM
as some of you know i have moved the fuel cell to the bed of my truck. i got a new in line fuel pump its a msd that runs about 40 pounds of pressure. i did not make any adjustments to anything on the motor. when i started it up it started fine but there seams to be alot of fuel that is not getting burn . there seams to be alot of fumes coming out the tailpipes now. the only thing i could think of was its way to much fuel pressure and i need to put a reguater on it. and bring it down some. what do you all think? could this be my problem and what would i need to set it at?



keep in mind i have a 383 with a holley 670 tbi . thanks all

CKTA
11-07-2005, 12:08 PM
You need to back that WAY down to about 15 or 16 #'s as a starting point. 40 is WAY to much.

no2guncntrl
11-07-2005, 12:11 PM
From a post over at an S series forum, a member there stated
the Holley will push some serious fuel through it's injectors. He
has one. Have you tried adjusting the fuel press down a bit ?
In fact what IS your fuel press ? Did you pipe in an external
reg like an Aeromotive unit ? It may be that the ECM is doing
all it can to control fuel, but is limited by it's programmed
fuel trim. Is there any chance the fuel return is blocked a
bit and not returning fuel like it should ?

Far as fuel press, I think anywhere from 13.5 to 15-16 #
would work out pretty good. Here is a nice little reg
from AM that would do the trick..>
http://store.summitracing.com/partdetail.asp?autofilter=1&part=AEI%2D13301&N=4294925239+4294839053+4294880914&autoview=sku

In fact here is one on E-Bay. I had one on my ride at one
time. Worked great. Comes with two different springs.
One for 3-20 the other for 20 to 60. >
http://cgi.ebay.com/Aeromotive-universal-fuel-pressure-regulator-13301_W0QQitemZ8012954063QQcategoryZ33553QQssPageN ameZWDVWQQrdZ1QQcmdZViewItem

mrflames
11-07-2005, 01:25 PM
thats the one i was looking at getting from summit

91s104x4
11-07-2005, 04:16 PM
TBIs come from the factory set between 9-13 psi. 12-13 is a good pressure for most TBIs.

The_Ogre25
11-08-2005, 12:38 PM
I would get a xternal regulator to bring it down to like 20 and then fine tune it at the tbi regulator. if you have one.