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Fuel pressure question....

Reply #30 –
Does running 19 lb/hr injectors with heads flowing at or similar to GT40 head rates go above 80% duty cycle? I have 19's in the red car and a GT40 setup, the silver cougar I used to have had that as well. Never had any fuel starvation issues. Red car is speed density, the silver one was mass air. That's all with stock 100k+ mile fuel pumps as well. Not to mention that I'm considering WOT usage here, where you would actually max out the injectors potentially. 1/2 throttle or less, even the S.O. 14-lb/hr injectors would probably function and give the car enough fuel to just putt around town.
1987 20th Anniversary Cougar, 302 "5.0" GT-40 heads (F3ZE '93 Cobra) and TMoss Ported H.O. intake, H.O. camshaft
2.5" Duals, no cats, Flowmaster 40s, Richmond 3.73s w/ Trac-Lok, maxed out Baumann shift kit, 3000 RPM Dirty Dog non-lock TC
Aside from the Mustang crinkle headers, still looks like it's only 150 HP...
1988 Black XR7 Trick Flow top end, Tremec 3550
1988 Black XR7 Procharger P600B intercooled, Edelbrock Performer non-RPM heads, GT40 intake AOD, 13 PSI @5000 RPM. 93 octane

Fuel pressure question....

Reply #31 –
You need adequate fuel delivery to make HP. We go through this every day. Guys build all kinds of engines and all kinds of combinations and run stock fuel pumps with reduced voltage. This is NUTS!!! The very first thing you need to do is install a good aftermarket pump. The 255 comes to mind with adequate voltage. I never have a problem delivering a good voltage supply to my PUMPS. That is the beauty of a trunk battery. You can slave out a relay controlled by the stock feed wire to activate the relays Mounted in the trunk and feed the contacts from the trunk battery. This way you have no voltage DROP whatsoever. There is more to a trunk mount BATTERY than meets the EYE!!! A one volt drop in applied voltage to a pump reduces it 's delivery capability by 14-18%. Thanks

NOTE using the stock fuel pump feed wire to activate the trunk mounted slave relays keeps all safety devices in OPERATION and that is a good thing!!

I spend money I don't have, To build  cars I don't need, To impress people I don't know

HAVE YOU DRIVEN A FORD LATELY!!

Fuel pressure question....

Reply #32 –
Quote from: ZondaC12;419422
Does running 19 lb/hr injectors with heads flowing at or similar to GT40 head rates go above 80% duty cycle? I have 19's in the red car and a GT40 setup, the silver cougar I used to have had that as well. Never had any fuel starvation issues. Red car is speed density, the silver one was mass air. That's all with stock 100k+ mile fuel pumps as well. Not to mention that I'm considering WOT usage here, where you would actually max out the injectors potentially. 1/2 throttle or less, even the S.O. 14-lb/hr injectors would probably function and give the car enough fuel to just putt around town.

@ what fuel pressure????????? They are very close to being at 90-95% i would think @ stock fuel pressure and delivery of the shiznitty stock pump!! Very questionable because you did not say if you have an UP-DATED pump and or stock Fuel pressure Thanks

NOTE low voltage at the pump also reduces it's life span by the same percentages APP 15%
I spend money I don't have, To build  cars I don't need, To impress people I don't know

HAVE YOU DRIVEN A FORD LATELY!!

Fuel pressure question....

Reply #33 –
I have a 255 lph pump. I have been so busy I haven't had time to get back under the hood and do some gauge checking or anything else. Saturday, I will. A battery will NOT go in my trunk. I like a clean, empty trunk.
'88 Sport--T-5,MGW shifter,Trick Flow R intake,Ed Curtis cam,Trick Flow heads,Scorpion rockers,75mm Accufab t-body,3G,mini starter,Taurus fan,BBK long tube headers,O/R H-Pipe, Flowamaster Super 44's, deep and deeper Cobra R wheels, Mass Air and 24's,8.8 with 3.73's,140 mph speedo,Mach 1 chin spoiler,SN-95 springs,CHE control arms,aluminum drive shaft and a lot more..

Fuel pressure question....

Reply #34 –
Trunk battery was not the issue. I just pointed out that there is more reasons to mount one in the trunk. There is other ways to increase or should i say decrease voltage drop. I like an engine without holes in the top of my pistons rather than an  EMPTY  TRUNK !!!!!!!!!!!!! But if you are having fuel delivery issues and low volume or pressure i would fix that pr0nTO. Thanks!!
I spend money I don't have, To build  cars I don't need, To impress people I don't know

HAVE YOU DRIVEN A FORD LATELY!!

Fuel pressure question....

Reply #35 –
I hope to know more Saturday. Doing the work that I do, and 12 hour shifts leaves little time for the Sport during the week. I'll report in with some news tomorrow.
'88 Sport--T-5,MGW shifter,Trick Flow R intake,Ed Curtis cam,Trick Flow heads,Scorpion rockers,75mm Accufab t-body,3G,mini starter,Taurus fan,BBK long tube headers,O/R H-Pipe, Flowamaster Super 44's, deep and deeper Cobra R wheels, Mass Air and 24's,8.8 with 3.73's,140 mph speedo,Mach 1 chin spoiler,SN-95 springs,CHE control arms,aluminum drive shaft and a lot more..

Fuel pressure question....

Reply #36 –
I know the feeling Vinnie those 12 hour days are tough. Good luck!!
I spend money I don't have, To build  cars I don't need, To impress people I don't know

HAVE YOU DRIVEN A FORD LATELY!!

Fuel pressure question....

Reply #37 –
Quote from: TOM Renzo;419431
@ what fuel pressure????????? They are very close to being at 90-95% i would think @ stock fuel pressure and delivery of the shiznitty stock pump!! Very questionable because you did not say if you have an UP-DATED pump and or stock Fuel pressure Thanks

NOTE low voltage at the pump also reduces it's life span by the same percentages APP 15%

Stock non-adjustable fuel pressure regulators and in both cases, a stock original fuel pump with at least 100k miles on it. I'm well aware that the stock pumps are barely adequate for 200 HP or so, I haven't had a problem yet so I haven't bothered to upgrade :hick: LOL. My black cougar with an entire Trick Flow top end setup and 24 lb injectors may or may not have an aftermarket fuel pump. Are they all louder than a stocker? When I click the key to IGN, the thing sure as hell sounds like a wimpy stock pump. How that car pulls like it does and doesn't cut out altogether is beyond me. The logical explanation would have to be an upgraded pump. Someday maybe I'll be REAL bored and drop it to find out...
1987 20th Anniversary Cougar, 302 "5.0" GT-40 heads (F3ZE '93 Cobra) and TMoss Ported H.O. intake, H.O. camshaft
2.5" Duals, no cats, Flowmaster 40s, Richmond 3.73s w/ Trac-Lok, maxed out Baumann shift kit, 3000 RPM Dirty Dog non-lock TC
Aside from the Mustang crinkle headers, still looks like it's only 150 HP...
1988 Black XR7 Trick Flow top end, Tremec 3550
1988 Black XR7 Procharger P600B intercooled, Edelbrock Performer non-RPM heads, GT40 intake AOD, 13 PSI @5000 RPM. 93 octane

Fuel pressure question....

Reply #38 –
i couldnt agree more on the voltage drop issue,,
stock layout for fuel pump power integrates three connectors plus the wire.. lots of opportunity for a resistance.

im going to for the helavit check my voltage to my pump,,

keep in mind i just found out the design of electric fuel pumps are based on Alternator volatage,,, 13.5v float voltage, not 12v,,, with such a low voltage every volt means soooooooooooo much.

Fuel pressure question....

Reply #39 –
I've been busy around here. Not much time for the Sport. I did check the gauge. At idle, it's holding on about 28psi. I am going to swap the FPR when I can (probably Friday due to my work schedule), and we'll see what happens. Fuel pump check after that if need be.
'88 Sport--T-5,MGW shifter,Trick Flow R intake,Ed Curtis cam,Trick Flow heads,Scorpion rockers,75mm Accufab t-body,3G,mini starter,Taurus fan,BBK long tube headers,O/R H-Pipe, Flowamaster Super 44's, deep and deeper Cobra R wheels, Mass Air and 24's,8.8 with 3.73's,140 mph speedo,Mach 1 chin spoiler,SN-95 springs,CHE control arms,aluminum drive shaft and a lot more..

Fuel pressure question....

Reply #40 –
Jay always remember the closer you get to the work the More Efficient things work. Example having a trunk mount battery brings more current and voltage to the pumps. Simple deduction less wire less voltage drop. Just an example. Thanks
I spend money I don't have, To build  cars I don't need, To impress people I don't know

HAVE YOU DRIVEN A FORD LATELY!!

Fuel pressure question....

Reply #41 –
I thought that point was already made, and, I already stated, no battery is going into my trunk.
'88 Sport--T-5,MGW shifter,Trick Flow R intake,Ed Curtis cam,Trick Flow heads,Scorpion rockers,75mm Accufab t-body,3G,mini starter,Taurus fan,BBK long tube headers,O/R H-Pipe, Flowamaster Super 44's, deep and deeper Cobra R wheels, Mass Air and 24's,8.8 with 3.73's,140 mph speedo,Mach 1 chin spoiler,SN-95 springs,CHE control arms,aluminum drive shaft and a lot more..

Fuel pressure question....

Reply #43 –
could measure your actual voltage drop to see if its a problem, then upgrade throughe wires going to the relay...
Quote from: jcassity
I honestly dont think you could exceed the cost of a new car buy installing new *stock* parts everywhere in your coug our tbird. Its just plain impossible. You could revamp the entire drivetrain/engine/suspenstion and still come out ahead.
Hooligans! 
1988 Crown Vic wagon. 120K California car. Wifes grocery getter. (junked)
1987 Ford Thunderbird LX. 5.0. s.o., sn-95 t-5 and an f-150 clutch. Driven daily and going strong.
1986 cougar.
lilsammywasapunkrocker@yahoo.com

Fuel pressure question....

Reply #44 –
In my view there is nothing more UGLY than an UNDER HOOD BATTERY. Just me
I spend money I don't have, To build  cars I don't need, To impress people I don't know

HAVE YOU DRIVEN A FORD LATELY!!