Fuel injectors/Pressure ?
 

Last year I installed 2 new fuel pumps and new injectors, one set from SAP and the other Accels. I pressurized the fuel system and it jumps to 57lbs of pressure then drops to 41 and within 5 minutes pressure is down to 30 or less. I know Dominic had this issue earleir, wondering if the SAPs are crap and are leaking.

Times at the track are down fromlast year, MPH was down 2-3mph from last year. I was running 113-114.5 vs 115-117 last year.

LGAFF
92 ZR1
#234

Re: Fuel injectors/Pressure ?
 

Tested the Inj for resistence results as follows:

2ndry= 1)12.5 2)12.4 3)12.4 4)12.9 5)12.8 6)12.6 7)6.9:jawdrop: 8)12.4


Primary= 1)15 2)15 3)15 4)15 5)14.8 6)15 7)15 8)15


Hmmmmmmmmm


LGAFF
92 ZR1
#234

Re: Fuel injectors/Pressure ?
 

Sucks, so which injector brand failed?

Re: Fuel injectors/Pressure ?
 

Change the damn injector,LOL
Did you go to Byron?


What as your 1/8 MPH
Was your 60ft the same as last time.

Did you make any changes to the car,chip tune, plugs,etc.

Pete

Re: Fuel injectors/Pressure ?
 

SAPs.... only 1 year old.......bought these off the bay. As I was nice enough to test these for the forum members please send your check or money order to Lee Gaffigan:D


Guess I know what I am buying next week.

LGAFF
92 ZR1
#234

Re: Fuel injectors/Pressure ?
 

Byron sucked.......

Started running 12.8s at 113, even realed off a 12.64. Speed was slow but that might be the injector. I think they worked out the timing issue both sides consistently sucked for me and 1/8ths seem consistent in MPH and times.

I was going to try one more run then a motorcyle engine blew just past the 1/8th....guy launched parts over the friggin fences on both sides. That was worth $25 right there. I got 8 runs in, could have done 12-15 but spent time trying to figure out what was wrong.

I might as well change the coils also. I wonder if SAP makes those

LGAFF
92 ZR-1
#234

Re: Fuel injectors/Pressure ?
 

I was running 8.3-8.4@ 89MPH on both sides fairly consistently. I was not getting the second half pull I am used to out of the car. I had the same issue when I went in early May. This also means my 391hp Dyno run was with a crap injector.

LGAFF
92 ZR1
#234

Re: Fuel injectors/Pressure ?
 

http://www.atlanticspeed.com/product...1527_thumb.jpg Accel 150121 (8) "Only $259.88" #150821 21# High Impedence Fuel Injectors. Ford 86-95 5.0L, 96-98 4.6L, GM 86-92 TPI, 93-97 LT-1, ZR1 ZR-1 Ford
Price $259.88
ACCEL 21#* High Impedance FUEL INJECTORS #150121 (Set of 8) Applications: GM V8 1986 to 1992 TPI GM V8 1993 to 1997 LT-1 FORD V8 5.0L 1986 to 1995 Ford V8 4.6L 1996 to 1998.
http://www.atlanticspeed.com/product...on_details.gifhttp://www.atlanticspeed.com/product...button_add.gif

Are these the ones I need??


LGAFF
92 ZR1
#234

Re: Fuel injectors/Pressure ?
 

Line pressure down to 30 psi in 5 minutes? The spec. in the Shop manual is only to hold pressure for 10 seconds once the fuel pumps are shut off. Per the manual, the system should show 48-55 psi while the pumps are running with the engine off. When the engine is started pressure should drop 3-10 psi.

I don't think 5 minutes is relavent here. Sounds to me like your system is just fine.

Didn't you change your tune from last year? Change it back and see how it preforms.

Hans
:cheers:

Re: Fuel injectors/Pressure ?
 

Hans,

My manual says system should drop some once pumps stop but pressure should be maintained, however look at the test on the injectors, one at 6.8 and thats cold I would imagine once heated that one is toast.

LGAFF
92 ZR1
#234