Max Fuel psi???

[HammerDown]

Whats the safe max Fuel psi I can run without needing a regulator? I'm thinking 8 lbs.
Looking at a new Holly Mech pump...I belive it said between 7-9 psi.
[ May 11, 2003, 02:05 PM: Message edited by: HammerDown ]

[wsuwrhr]

7-9 is max as long as you aren't running the Baja 1000 bouncing up and down. haha. I run all mine at 7-8. Mechanical pump should be ok without a reg, but why do you want to do that?
Brian
[ May 11, 2003, 03:41 PM: Message edited by: wsuwrhr ]

[HammerDown]

wsuwrhr:
7-9 is max as long as you aren't running the Baja 1000 bouncing up and down. haha. I run all mine at 7-8. Mechanical pump should be ok without a reg, but why do you want to do that?
Brian Don't really want to plum in a regulator. And a friend has a new Holley Mech pump for me...7-9 psi, If I want it.

[Fiat48]

Holley makes more than one mechanical pump. One requires a regulator. Be sure of which one you are getting for if you try to run the one without a regulator, it will knock the needles and seats right off and flood the motor. Regulators have improved and are not as restrictive as they once were.

[Hotcrusader76]

HammerDown:
Whats the safe max Fuel psi I can run without needing a regulator? I'm thinking 8 lbs.
Looking at a new Holly Mech pump...I belive it said between 7-9 psi. That is correct, 7-9PSI. Anything more an the needle mechanism will not shut and you'll end up over-filling the bowls.
~Ty

[GofastRacer]

HammerDown:
Whats the safe max Fuel psi I can run without needing a regulator? I'm thinking 8 lbs.
Looking at a new Holly Mech pump...I belive it said between 7-9 psi. Personally, I wouldn't go over 8lbs, if you don't want to run a regulator, you can always use a bypass set at 8lbs "AFTER" the carbs!.. :cool:

[Fiat48]

GofastRacer:
HammerDown:
Whats the safe max Fuel psi I can run without needing a regulator? I'm thinking 8 lbs.
Looking at a new Holly Mech pump...I belive it said between 7-9 psi. Personally, I wouldn't go over 8lbs, if you don't want to run a regulator, you can always use a bypass set at 8lbs "AFTER" the carbs!.. :cool: Forgot about doing that. That gets rid of the regulator restriction and was a sweet deal when we used to run carbs. Never had a flooding problem. Best idea.

[GofastRacer]

Yeppp!.. :)

[Fiat48]

Been away from carbs a long time. But when I used to run pro gas flat, I did some testing with a Holley 110 pump and a regulator. The regulator caused the actual free flow fuel delivery to be cut down to 55 GPH. Plus the cheap little Holley regulators would stick and flood the engine, usually at the starting line. The bypass system solved the problem and got the fuel delivery back to what we wanted. When we went to injection, we never went back to carbs.

[HammerDown]

Educate me about the Bypass "after the Carb"...I'm lost on that one.
Thanks

[Racing Ray]

Holley does sell high pressure needle and seat units that are good to 11PSI if you are worried. They should be available at any speed shop.

[Infomaniac]

HammerDown:
Educate me about the Bypass "after the Carb"...I'm lost on that one.
Thanks I will post a pic this evening.

[GofastRacer]

Fiat48:
Been away from carbs a long time. But when I used to run pro gas flat, I did some testing with a Holley 110 pump and a regulator. The regulator caused the actual free flow fuel delivery to be cut down to 55 GPH. Plus the cheap little Holley regulators would stick and flood the engine, usually at the starting line. The bypass system solved the problem and got the fuel delivery back to what we wanted. When we went to injection, we never went back to carbs. I hear ya, that's why I'm going back to these!.. :cool:
http://www.***boat.com/image_center/data/500/12My_Crowers.jpg

[GofastRacer]

HammerDown:
Educate me about the Bypass "after the Carb"...I'm lost on that one.
Thanks This is one example of what I ran but there are other type bypasses you can get. The thing is to put the bypass after the carb(s)have been fed not between the pump and the carb!..
http://www.***boat.com/image_center/data/500/12Carb_Bypass-med.jpg

[HammerDown]

GofastRacer:
HammerDown:
Educate me about the Bypass "after the Carb"...I'm lost on that one.
Thanks This is one example of what I ran but there are other type bypasses you can get. The thing is to put the bypass after the carb(s)have been fed not between the pump and the carb!..
http://www.***boat.com/image_center/data/500/12Carb_Bypass-med.jpg Hmmmm, thanks for the pic...but dosent that show the bypass between the pump and carb? (scratching my head).
After the carb is feed, hows that? I'm not getting the picture here :confused:

[HammerDown]

OK...I'm guessing that little Gold thingy...is pre set to maybe 8 lbs. so as to only alow that much pressure through...correct?
And if so, what is it goes bad= not good!

[GofastRacer]

HammerDown:
GofastRacer:
HammerDown:
Educate me about the Bypass "after the Carb"...I'm lost on that one.
Thanks This is one example of what I ran but there are other type bypasses you can get. The thing is to put the bypass after the carb(s)have been fed not between the pump and the carb!..
http://www.***boat.com/image_center/data/500/12Carb_Bypass-med.jpg Hmmmm, thanks for the pic...but dosent that show the bypass between the pump and carb? (scratching my head).
After the carb is feed, hows that? I'm not getting the picture here :confused: The bypass is toward the tank, on the oposite end would be the line directly from the pump. That way you have full pressure to the carbs. Over 8lbs, the bypass will bleed off the extra pressure but the carb will always have full pressure. If you tee in the bypass between the pump and the carb, you may not get full pressure at the carb..

[GofastRacer]

HammerDown:
OK...I'm guessing that little Gold thingy...is pre set to maybe 8 lbs. so as to only alow that much pressure through...correct?
And if so, what is it goes bad= not good! All that is is an injector bypass with a spring and poppet set to 8lbs...

[HammerDown]

Got it...thanks.

[GofastRacer]

Glad to be of help!.. :)

[Boater Bill]

Racing Ray:
Holley does sell high pressure needle and seat units that are good to 11PSI if you are worried. They should be available at any speed shop. Hey Ray, welcome back. :D

[Infomaniac]

The two #8 fittings on the left will go to a BG bypass. Nothing in the path of the fuel to restrict flow.
http://www.***boat.com/image_center/data/504/211Fuel_Lines-med.jpg

[Hotcrusader76]

This type of bypass has been used alot on ALky set-ups. I know the oval track racers we've delt with like this set-up when useing the mechanical belt driven pumps.
~Ty

[fat rat]

I run a simular system also, my pump puts out 15 psi and my bypass is set for 8lbs. it eliminates the need for a regulator..........but I have one question, My gauge was at 15 psi, the bypass/ pressure regulator was hung up and I never flooded the motor........was I just Lucky.

[GofastRacer]

Infomaniac:
The two #8 fittings on the left will go to a BG bypass. Nothing in the path of the fuel to restrict flow.
http://www.***boat.com/image_center/data/504/211Fuel_Lines-med.jpg Yep, the only way to do it, looks nice Ron!.. :cool: