ioTus

iTrader: (5)

I'm almost sold on the Mallory 4305M regulator, which does 30-100psi adjustability.

Are there any others I should be considering?

Also wondering what gauges are working well, or rather, which gauges are NOT working well for folks. I'm inclined to get a $20 inline gauge, but I would rather not have it break and leak.

Starfox07

I'm using a Mallory 4309 in my carb setup, and I'm pleased. It's built very well. I'm using some cheapo $12 gauge in line, but mine only sees maybe 3psi. I'd say go for the $20 gauge. I doubt it will break, although the accuracy might not be great.

ioTus

iTrader: (5)

Yah I had the 4309 on my blowthrough, loved it.

TheDriver216

iTrader: (2)

been using and aeromotive 13301 for my carb set ups... no issues, comes with a 3-20 psi and 20-65 psi spring

ioTus

iTrader: (5)

The thing is I need to know specifically for EFI as they deal with a vastly different fuel pressure, 30-100psi range.

TheDriver216

iTrader: (2)

the 20-65 psi spring is for efi... its a return style regulator good for carb AND efi with boost reference... for NA why would you need 100psi anyways...

j9fd3s

iTrader: (3)

one of the things i wanna try in an NA is running higher fuel pressure

ioTus

iTrader: (5)

i didn't catch the 20-65 spring part, my bad. The stock EFI system puts out around 75psi i believe, @ the injectors it sees anywhere from 38psi to 70psi depending on throttle position, load, etc.

fidelity101

iTrader: (11)

Yeah I run this one too, should I ever go back to EFI I just swap the spring!

ioTus

iTrader: (5)

I mean no disrespect but I'd need to hear that from some folks who actually have experience w/ aftermarket rotary EFI builds and FPR

FullFunctionEng

iTrader: (13)

We really like the Fuelab mini FPR's.

fidelity101

iTrader: (11)

Yes, I have actual experience in this.

ioTus

iTrader: (5)

Ah excellent, my bad I misunderstood.

So 60psi is enough to handle full load WOT? The engine has stock s5 injectors and a large streetport, Haltech F9 fuel computer

Pettersen

iTrader: (1)

Isn't the stock fpr around 38psi above manifold pressure?

j9fd3s

iTrader: (3)

yep, so 38psi + 0 = 38psi, so 65 should be fine :P

TheDriver216

iTrader: (2)

plus if you need 65lbs fuel pressure i think its time for bigger injectors... the pump will be screaming and not flowing as much either...

ArmyOfOne

iTrader: (12)

I run the 4309 with 1/2" lines. No problems at all.

diabolical1

iTrader: (3)

question on the 4305m ...

i'm finally at the point where i'm setting mine up and i'm curious. for you guys that are running one, how did you setup the return line(s)?

1. did you run the stock return into regulator's return (using a "Y" or similar method)?

or

2. did you dead-end the stock return and just use the regulator's return?


on a total sidenote, holy **** these AN fittings really add up!

peejay

Never run an inline pressure gauge, they always break, even the expensive ones.

Get a remote mount, or put a -4 male fitting on a tee. Install a GM fuel pressure gauge on it when you want to check/change pressure, and cap it off the rest of the time.

Awful nice of GM to make their fuel pressure test ports -4 AN, wasn't it?

ArmyOfOne

iTrader: (12)

I had my return T into the fuel spout vent line since it is a -8