Just received holly efi fuel pump

[motorheadmike]

You can get them with a 340lph pump too 😉

Keep going!

 

[Northernregal]

You can get them with a 340lph pump too 😉

 

[81cutlass]

You can get them with a 340lph pump too 😉

I needed two fo-fiddies (450's) for corn on 58base plus 12 for boost compensation and I'm only making 10 second power :0

 

[JAMCAR223]

It took 3 months for Holley to deliver mine. ( #12-306 ) I don't have a turbo on this car, so this pump is plenty for my mild 403 SBO.

• This in-tank fuel pump module is a high-pressure unit that flows 255 liters per hour (LPH) and is capable of supporting electronic fuel injection (EFI) engines producing up to 550 horsepower

 

[Tony1968]

I was sent a 340 for free from Holley after my 255 was dead on arrival. Well actually it sounded like muffled marbles in a can and couldn't hit 50 psi. 340 is quiet as a mouse.

 

[64nailhead]

Mine are noisy as hell, that's how I know they're workin'. They even change pitch a little when the tank gets low - I call it the 'low fuel alert'.


Kidding aside, a 255 or 340 is plenty of pump for 95% of the builds out there that want to use a stock tank with an in tank pump. A single 340 will handle just about any streetable, NA build. and a 255 isn't far behind it.

Regarding replacements, if these pumps are genuine, or at least the same dimension, as a 340 or 255 Walbro, then replacements are readily available and economical. Way to go Holley on making a direct fit part.

 

[64nailhead]

I had no idea that even existed..

Have to stop surfin' the lemonade stands for yellow bikinis to find items like these

 

[Streetbu]

I needed two fo-fiddies (450's) for corn on 58base plus 12 for boost compensation and I'm only making 10 second power :0

If you need that much pump and power for 10's something isn't right...

 

[melloelky]

Have to stop surfin' the lemonade stands for yellow bikinis to find items like these

 

[64nailhead]

If you need that much pump and power for 10's something isn't right...

Jake's right, a single 450 is very difficult to get a 3500+lb vehicle into the 10's with more than 10 psi of boost. NA it could be done, but the boost deal requires more pump. At least imho. One thing that is often overlooked in these calculations is the additional fuel pressure needed to maintain the same amount of fuel delivery as an NA vehicle requires to make the same BSHP. The pumps become less efficient as the pressure increases.

This is a quite common situation that's well documented as illustrated above. It is the main reason to not run a stock GM regulator at 58 psi if you have an engine management system that tune for a lower base pressure.