[SeventyNova]

I have a 383 in my nova with a 150 shot on it. With the old holley mech pump I was dropping to 3 psi fuel pressure at wot without the juice being hit. I added a holley blue pump by the tank to boost the pressure and set the regulator to 7-8psi at idle. When I run it up it still drops to 4 psi without the juice.

I am considering a few things to try as I want the pressure at 6 or above consistantly:

1) I have it running through the mech pump still, should I bypass it?

2) increase the pressure at the regulator

3) add a return line and set the fuel pressure with it in place

What would you guys reccomend? The car had 3/8" fuel line right now.

Thanks

Jon

 

[luepke75]

Try bypassing the mech. pump. I have used the Blue for years on motors and it shouldnt be dropping like that. Im not a Nitrous guru but many on here can tell you if the Blue will work for both and keep preasure.

 

[SeventyNova]

Anyone else have any ideas before I start changing stuff?

 

[Pro19Nova67]

I would bypass your original pump. I've never heard of anyone using both an electric and mechanical pump. That's at least a free and easy try.

I have to say, I'm not a big fan of Holley fuel pumps. I could never get one to last more than a year before it developed a leak or just stopped working altogether. I've been really impressed with my Mallory fuel pump.

 

[novaray64]

I would try bypassing the mech pump and check the fuel lines for any restrictions. There might be a screen on the draw straw in the tank that could be plugged. Have you checked your fuel filter? The holley blue pump shouldnt have any problems feeding your engine

 

[D-Man]

Yeah......bypass the mechanical pump first and give it a shot.
Is the 3/8" line the factory line? It's VERY possible it might have a kink or restriction somewhere that's limiting the flow.:yes: Bypassing the mechanical will be telling... :yes:

 

[slickman]

Bypass the mech pump.

 

[hotrod69nova]

bypass the mechanical pump.and if it still doesn't come up enough go to a black pump.

 

[SeventyNova]

The 3/8" line isn't stock, its relatively new and so is the pickup, the fuel filter is also new.

I will try bypassing the mech pump

 

[The Big Al]

bypass the mechanical pump.and if it still doesn't come up enough go to a black pump.

I agree.

Also Moroso makes a check valve spring that ups the pump pressure.
Moroso # 65770
Boost the output of your electric fuel pump.
These Moroso fuel pump springs are designed to increase the pressure of your Holley electric fuel pump. They are made of high-strength stainless steel and will increase pressure over stock. The springs will also increase overall fuel volume while maintaining your fuel pump's reliability.


I have used Holley for years and never had a problem. Had to rebuild a few after sitting during the winter.

Purchased a High Dollar Aeromotive and it let me down at pinks! So back in with the Holley Blue! (Aeromotive did correct the pump N/C) I have also used Aeromotive pumps on Boats without any issue for long hours!!


Al

 

[underatree]

Yeah......bypass the mechanical pump first and give it a shot.
Is the 3/8" line the factory line? It's VERY possible it might have a kink or restriction somewhere that's limiting the flow.:yes: Bypassing the mechanical will be telling... :yes:

X2.I had the same problem.Installed a new pump and all kinds of stuff.Still not enough pressure.Turns out the fuel line had a bunch of crud in it.No matter how new it is still may have some crud in it....

Just a suggestion.It would have saved me ALOT of trouble and money had I found it sooner!