|
This THREAD brought to you by... |
|
 |
Official Member
|
|
Posts: 168
Join Date: January 2006
Location: Virginia
|
|
|
injectors maxing out -
09-17-06, 11:06 AM
I'm having trouble with my 42lb injectors maxing out at high rpm and under boost, I have a 255 in the tank and a propump inline and a boost sensitive regulator, I have raised the fuel pressure to 58 with vac off and the injectors are still maxing out. It is a 302 shortblock and the rest is in my sig, Are my rails and lines too small or what's going on? I thought the stock rails could handle this type of setup?
AFM PMS, LM1 wideband,ATI PROCHARGER 9lb, 3 core intercooler, AFR 165cc, 75 mm throttle body, EGR plate, comp cam, edlebrock performer upper and lower ported,pro-m 3-inch mass air, 42lb injectors,Mallory afr, 1.6 rr, msd 6al ignition, BBK long tubes, BBK off road xpipe, flow master cat back, TKO 500, Spec stage 3+ clutch, aluminum drive shaft, 3.73s auburn pro,33 spline mosers, drag launch springs.12.79 spinning,before blower 
|
 |
Official Member
|
|
Posts: 131
Join Date: May 2005
Location: queens, ny
|
|
|
10-02-06, 06:40 PM
try adding a fmu it will bring your press up under boost and allow more fuel in during the cycle.
91 Gt Convertible
RNH Perfomance 331 dart stroker, scat 4340 crank, scat h-beam rods, afr 185 heads, s-trim, efi spyder intake, 80mm tb, 80mm mass air, 42lb injectors, 3.73's tremec 5-spd. mac 1 3/4 ceramic coated long tubes, and all the other bolt ons.......
Last edited by joeyd0730; 10-02-06 at 07:08 PM.
|
 |
Founding Member
|
|
Posts: 442
Join Date: September 2002
Location: Dudley, MA
|
|
|
10-03-06, 08:48 AM
How much power are you making, you shouldnt be even close to max... I run stock lines, stock filter, one pump in tank, and stock rails and I'm just maxing out now...
A FMU is a tuning band-aid that comes with the kit. Its not a permanent, nor a good solution.
1993 LX 5.0 T5 Notch - Twin Turbo -
(2) T04B's, (2) Tial 38mm gates, Vecco FMIC, Hallman Pro MBC, Greddy Type S BOV
Stock shortblock, E7 heads, Comp cam, GT40 intake, 42# injectors
531 RWHP, 557 RWTQ @ 16 psi
217 quarter mile runs and counting
2003 WRX (its blue obviously)
231 AWHP, 229 AWTQ @ 17 psi
|
|
Official Member
|
|
Posts: 168
Join Date: January 2006
Location: Virginia
|
|
|
10-30-06, 05:24 PM
Took a while to get a reply on this so I didn't check until now. I am supposed to be making around 500ish, hp, on my PMS screen at about 58k I max out to 100% but I don't go lean. I talked to Rick Anderson about this and he said it was okay as long as I didn't go lean. I am running about 58psi fuel pressure at max boost. I have all stock fuel rails and lines, a 255 intank and a propump inline. No fmu, don't want one.
AFM PMS, LM1 wideband,ATI PROCHARGER 9lb, 3 core intercooler, AFR 165cc, 75 mm throttle body, EGR plate, comp cam, edlebrock performer upper and lower ported,pro-m 3-inch mass air, 42lb injectors,Mallory afr, 1.6 rr, msd 6al ignition, BBK long tubes, BBK off road xpipe, flow master cat back, TKO 500, Spec stage 3+ clutch, aluminum drive shaft, 3.73s auburn pro,33 spline mosers, drag launch springs.12.79 spinning,before blower
|
 |
Official Member
|
|
Posts: 453
Join Date: December 2005
|
|
|
11-19-06, 07:35 AM
Strange the chart on the MSD web site says you can make 500hp on 36lb injectors. What size are the injectors on the GT500?
Distilling your own fuel is legal, with a free permit issued by the Federal Government. Not only that, but you will qualify for a 38 to 60 cent per gallon Tax Refund for every gallon you distill.
Feel free to PM me.
|
 |
GoldMember
|
|
Posts: 1,938
Join Date: April 2000
Location: Alabama
|
|
|
11-22-06, 04:30 PM
42# injectors max out around 480-500 on blower cars. Upgrade to some 55-60 pounders and turn your fuel press back down to around 40 psi. You will be good to go after that
www.streetstangs.net
93 Cobra.....sold
01 Cobra vert....wife's
84 SVO........new project car
03 F250
08 GT
|
 |
Official Member
|
|
Posts: 137
Join Date: January 2006
Location: Port Orchard, WA
|
|
|
11-27-06, 04:21 AM
I would say get begger injectors and bigger fuel rails!
-Red 93GT Turbo 6spd
No numbers yet 
-89 Notch 5.0 5spd. Former 4cyl auto.
|
|
Founding Member
|
|
Posts: 442
Join Date: September 2002
Location: Dudley, MA
|
|
|
11-27-06, 02:52 PM
ding ding ding we have a winner!
The stock fuel lines cant support 42's never mind bigger. If you had a gauge you could watch during the pull, I bet you're losing at least 20 psi fuel pressure by the time you hit 5 grand. This is what happens when you have stock fuel lines/rails. They just get sucked dry:
The injectors dont run out of flow, the flow to the injectors runs out. I started at 80 psi at idle, had 40 psi at 4 grand and only 25 psi by 5.5 grand (fuel pressure) with stock lines and rails.
1993 LX 5.0 T5 Notch - Twin Turbo -
(2) T04B's, (2) Tial 38mm gates, Vecco FMIC, Hallman Pro MBC, Greddy Type S BOV
Stock shortblock, E7 heads, Comp cam, GT40 intake, 42# injectors
531 RWHP, 557 RWTQ @ 16 psi
217 quarter mile runs and counting
2003 WRX (its blue obviously)
231 AWHP, 229 AWTQ @ 17 psi
Last edited by VG30DE; 11-27-06 at 02:53 PM.
|
|
GoldMember
|
|
Posts: 1,938
Join Date: April 2000
Location: Alabama
|
|
|
11-27-06, 03:52 PM
Quote:
|
Originally Posted by VG30DE
ding ding ding we have a winner!
The stock fuel lines cant support 42's never mind bigger. If you had a gauge you could watch during the pull, I bet you're losing at least 20 psi fuel pressure by the time you hit 5 grand. This is what happens when you have stock fuel lines/rails. They just get sucked dry:
The injectors dont run out of flow, the flow to the injectors runs out. I started at 80 psi at idle, had 40 psi at 4 grand and only 25 psi by 5.5 grand (fuel pressure) with stock lines and rails. |
I have to disagree. I have run both 42's and 60's with stock fuel rails with no problems whatsoever. If you lose 20 psi during a pull than there is something else wrong in the fuel system. If you lost a lot of fuel psi on your combo with 42's, it was due to a faulty pump.
I could possibly see a fuel rail upgrade around 700rwhp and up but not any power level below that.
Which brings me to another question. Why in the world would you have your psi at 80? That kills injectors having that much pressure on the back side of them.
www.streetstangs.net
93 Cobra.....sold
01 Cobra vert....wife's
84 SVO........new project car
03 F250
08 GT
Last edited by LEE93COBRA; 11-27-06 at 03:58 PM.
|
|
GoldMember
|
|
Posts: 1,938
Join Date: April 2000
Location: Alabama
|
|
|
11-27-06, 04:02 PM
another thing..
When I was blown and at the power level you reflect in your graph, I had 60# injectors, stock rails, stock lines, 255 intank and a KB BAP. At WOT my car would hit 50 psi of fuel and hold while maintaining low injector duty cycle.
I actually had started out with 42's but they were not enough injector for 525-530rwhp
|
 |
Official Member
|
|
Posts: 623
Join Date: September 2005
|
|
|
01-03-07, 11:58 PM
check fuel pump, filter or put a in-line extra pump at least 67GPH!
88 LX Hatch
347 10.5 CR, typhoon intake ported, 70mm TB, 75mm maff, 30 pounds injectors, aeromotive FPR, 190LPH holley pump, AFR 185's, 1.6 RR's, Complete comp cams valvetrain, Mac 1 3/4 LT's 2.5 Xpipe flows and 3" tailpipes, stock T5, 3.90 gears.....
|
|
Founding Member
|
|
Posts: 880
Join Date: July 1999
Location: Marengo,Ohio,US
|
|
|
01-04-07, 12:02 AM
I make 535 rwhp with stock rails it sounds to me you have a weak FP or a voltage drop. Have you went with a 130a alternator yet to support the voltage drain.
TwinTurboIntercooler(TTi)
|
|
Official Member
|
|
Posts: 131
Join Date: May 2005
Location: queens, ny
|
|
|
01-22-07, 04:11 PM
by any chance are you running a c&l mass air meter?
91 Gt Convertible
RNH Perfomance 331 dart stroker, scat 4340 crank, scat h-beam rods, afr 185 heads, s-trim, efi spyder intake, 80mm tb, 80mm mass air, 42lb injectors, 3.73's tremec 5-spd. mac 1 3/4 ceramic coated long tubes, and all the other bolt ons.......
|
|
Member
|
|
Posts: 31
Join Date: February 2007
Location: mass
|
|
|
02-28-07, 05:41 PM
iImake 538 rearwheel with 36 pound injecters and i'm safe on the dyno also dont run the fmu
Last edited by lvboost; 02-28-07 at 05:43 PM.
|
 |
Founding Member
|
|
Posts: 1,784
Join Date: May 2002
Location: MI (Lansing/Howell/Farmington Hillls)
|
|
|
03-01-07, 07:27 AM
Quote:
Originally Posted by lvboost
iImake 538 rearwheel with 36 pound injecters and i'm safe on the dyno also dont run the fmu
|
You may be safe on the dyno but by no means is it recommended. Your likely pushing those injectors past 100% duty cycle and your fuel pressure has to be way high to compensate for your improper sized injectors.
1989 lx 5.0 (notch)
TFS Track Heat heads, 1.7 rr's, f303 cam, Megasquirt ecu, twin .60/.48 turbos@8psi, Tremec 3550, 42lb injectors, 255 fuel pump, 24x12x3 intercooler, Edlebrock Performer Intake, Nitto 275 40 17's, 3.27's, AJE Tubular k-member/A-arms, UPR Lowers, Ford Uppers, 99 Disc Brake Conversion
Best 1/4: 11.67 @ 127.84mph 489rwhp/527rwtq
http://videos.streetfire.net/video/3...ea0150d4a0.htm
|
|
Member
|
|
Posts: 31
Join Date: February 2007
Location: mass
|
|
|
03-01-07, 05:41 PM
your right and i'm going to do a fuel system asap but this is going on mt 4th season with this set up "and i do kill my car"and it takes it like a champ
|
| Thread Tools |
|
|
| Display Modes |
 Linear Mode
|
Posting Rules
|
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts
HTML code is Off
|
|
|
|
|
