Author Topic: Fuel pressure issue  (Read 2629 times)

Offline old cars

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Re: Fuel pressure issue
« Reply #15 on: September 21, 2021, 09:53:29 AM »
There are advantages to fluid filled fuel pressure gauge. Just keep temperature ( heat soaked ) in mind.
Obviously mounting matters. If you can't figure it out then read it cold.

Offline old cars

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Re: Fuel pressure issue
« Reply #16 on: September 23, 2021, 09:11:57 AM »
Installed one of these yesterday on a BBC . 7 PSI  Edelbrock 1722

Offline Too Fast

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Re: Fuel pressure issue
« Reply #17 on: October 01, 2021, 02:15:20 PM »
I emailed Holley about this pump and told them to give me some straight talk.  2 weeks ago.  No response.  So, it is still on order.  I am still having the issue.  Hot weather, the pressure tanks to 0, sometimes at the top of first gear, other times in 2nd.  IDK what I am gonna do yet.  I might return it, or try to install it, maybe run all new lines too.  Maybe mount an external noisy pump with a regulator. 

My fuel pressure gauge has a sending unit plumbed into the 3/8 fuel line, 8" before the carb, with the gauge itself in the car.

Offline Too Fast

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Re: Fuel pressure issue
« Reply #18 on: September 15, 2022, 02:19:07 PM »
Update on this fuel pump.  I had some frustration with fuel leaking at the top seal on the gas tank.  When I dropped the tank to inspect, everything looked ok until I took the pump out. The top of the tank sheet metal was warping around the seal area.  My final fix was to weld a reinforcement ring I made from a piece of sheet metal.  No I didn't die or explode haha.  With an X-ring instead of the foam mat the pump came with, I have no more leak.

Also, the pump itself has been reliable, and my hot fuel pressure issue is resolved.

4 weeks ago I installed  a Tremec TKX 5-speed,  and what a transformation to the car I've had since 1999.  If anyone is on the fence about a TKX conversion,  I say go for it. 

Offline lightning boy

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Re: Fuel pressure issue
« Reply #19 on: September 16, 2022, 01:12:44 PM »
I would eliminate the mech pump altogether and install a new tank with an electric pump with larger lines. be sure to run a dedicated return line with the regulator after the carb. Instead of using the Holley pump you would be much better off with a pump meant for a production car. A Bosch 044 or a pump from a mid-90's Supra would feed anything to 700HP. When people talk about noisy pumps what they are hearing is the pump cavitating. Don't put big filters before the pump or mount it on the frame, the suction head will be too low. That's why the factory put them in the bottom of the tank. There they have about .5 PSI at the pump inlet. If if you're not careful with the install  the suction head goes negative ,which is what you don't want.

Offline Too Fast

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Re: Fuel pressure issue
« Reply #20 on: September 21, 2022, 01:19:39 PM »
^^^ I plan on eliminating the mechanical pump after this electric setup proves reliable.  So far, so good but the pressure does drop to about 4 psi at the top of 2nd gear, but so far no lower.