ok so my v8 has been running for a bit as many of you know, but it wont run right becouse i cant get the fuel pressure down. it the holley pressure regulator that archie sends with his kit and no matter what i do when the fuel pump comes on the gauge pegs at like 20 psi. idling it will bounce from 20-12 psi. the regulator screw is all the way out becouse i was playing with it. it lowered the pressure but not enough. Also from the regulator it goes to 1/8 npt to the gauge and carb. ------------------
[This message has been edited by hiller21c (edited 04-28-2005).]
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03:02 PM
PFF
System Bot
GKDINC Member
Posts: 1813 From: East Tawas MI Registered: Dec 2001
I believe so. The 4 cylinder pump only produces about 9psi, where the v-6 is over 30. Someone else with more experience will chime in soon I'm sure. Good Luck Thanks Gary
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03:42 PM
p8ntman442 Member
Posts: 1747 From: portsmouth RI Registered: Sep 2003
well that makes alot of sence. im contimplating just getting a better pressure regulator from mallory that will handle the pressure, rather than buying a 4cly pump then droping the tank and instaling it.
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03:48 PM
Master Tuner Akimoto Member
Posts: 2267 From: South Florida,USA Registered: Jul 2003
Yes. You need to run the 4 cyl pump or get a bypass regulator. You can also make a bypass like I did:
I ran the line from the pump to a tee, then ran one side of the tee to a regulator, then the carb and the other side of the tee to a needle valve, then the return line back to the tank. I adjust the needle valve until I get about 10 psi to the regulator, then I adjust the regulator down to about 6. The rest of the fuel is returned to the tank just like in a fuel injection setup.
Sounds complicated, but it sure beats dropping the tank!
------------------ 1986 SE 350 V8
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03:55 PM
hiller21c Member
Posts: 401 From: hopkinton, MA Registered: Apr 2002
ok thanx for the info guys now i just gata figure out what route i wana go. better regulator of new fuel pump. ok well now i got another option as i was typing the one sentince above how did u route the fuel back into the tank?
[This message has been edited by hiller21c (edited 04-28-2005).]
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03:56 PM
GKDINC Member
Posts: 1813 From: East Tawas MI Registered: Dec 2001
For my own information, Is it a good idea to install the FPR direct to the carb like that or does it matter???? Seems to me that it might soak up allot of heat. Thanks Gary
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04:04 PM
hiller21c Member
Posts: 401 From: hopkinton, MA Registered: Apr 2002
ya i think i might be moving the regulator. i didnt think about the heat when doin it but it made a nice transition from the fuel line to the carb so i did it that way.
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04:07 PM
PFF
System Bot
jelly2m8 Member
Posts: 6254 From: Nova Scotia, Canada Registered: Jul 2001
The V6 pump has the ability of pumping 80+ psi of pressure, the 4 cylinder one 30 psi or so. The regulator probably cannot control that amount of pressure comming from the V6 pump.
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05:18 PM
buddycraigg Member
Posts: 13606 From: kansas city, mo Registered: Jul 2002
You can use the regulator and the pump you have if you plumb it right.
Take the supply line and install a T. 1 path goes to the carb, the other to the inlet of the regulator. The outlet of the regulator goes back to the tank. This makes your regulator a bypass type and it can easily be regulated down to and maintain 4psi without any pressure creep even with a V8 TPI fuel pump.
