h.o.ls1

iTrader: (2)

just put a sbc in a 96 v6 car and im wondering a couple things about my fuel delivery ... i still have the stock mechanical pump on the motor and was wondering if i let the in tank factory pump push fuel from the tank to there will it over fuel the mechanical one? or if i get a fuel pressure regulator will i be able to turn down the fuel pressure from 65 psi or whatever it is stock to the 8 psi i need to get to the carb?

ZONES89RS

iTrader: (25)

To the mech pump, it will burn the factory pump up, a regulator to 6 PSI operating range...will burn the factory pump up. Some return style regulator out there MIGHT work, but i havent found one yet that can manage that much bypass without damaging the higher pressure pump or the regulator.

raped 95Z

the stock in tank pump pushes far too much pressure and hes right regulating it to 6psi will fry the stock pump. your best bet is to buy like a holley blue pump and regulator put a fitting in your stock tank and let it rip. tune your fuel pressure to 6.5-7PSI at the carb. should be golden

1 FMF

iTrader: (1)

maybe i am missing something, but how can you hurt the intank electric pump by putting a regulator upstream of it? doesn't the intank pump already have a regulator on it?
from the intank pump's perspective, having a regulator dropping pressure to 6psi just before the carb is no different than the fuel being stopped at the fuel rails and injectors when the engine is idling, or not running at all. I fail to see how you would burn up the intank pump by adding a regulator, or anything for that matter, upstream of the intank pump or at least upstream of the regulator in the system maintaining the stock 65 psi.

ZONES89RS

iTrader: (25)

The problem is, the regulator is made to convert from 14 PSI down to 3 lbs on up to 12 or so, dropping from 50 or more PSI is really straining things, not intended for that. It will work, but for how long? Not long at all i think.

1 FMF

iTrader: (1)

let me ask this, cause i'm not familiar with the specific system the original poster is talking about,

provided that the regulator is on the intank pump, which is what allows that intank pump to maintain the 65psi.... or, if there is not a regulator on the intank pump then it would be located somewhere upstream like just before the fuel rail in which case there would be a return line sending that excess fuel back to the gas tank so the intank pump doesn't burn up. Now, if you add anything after wherever that original regulator is located, how can you hurt the intank pump? This is just rephrasing my original question.

regarding adding a regulator, unless you are supplying it with 1000+ psi of pressure you aren't going to hurt it, certainly not with < 100 psi. They are simple spring loaded regulators, there limit is really whatever the metal body and threaded fittings can withstand, and there is nothing special inside them.
i'm talking about something like this jegs 2-port adjustable for $25

TooLateVTEC

iTrader: (2)

I thought stock they were like 45 psi?

Is this a DD, weekend cruiser, or what?

If its not a DD, I would just stick this FPR on it:
http://store.summitracing.com/partde...5&autoview=sku

You have one inlet for the fuel line, and 3 outlets. One outlet to the carb, one for the return line, and one capped off/put a fuel pressure gauge on it.

I did this on my 87 IROC when I went from TPI (38psi) to Carb'd.

ZONES89RS

iTrader: (25)

I dropped the tank and mounted a external holley blue after removing the in tank pump.

h.o.ls1

iTrader: (2)

figured it out just had the line that goes to the stock fuel pump cut and a new metal line brazed on with a filter in line and it just sits on the bottom of the tank...works perfect!

ZONES89RS

iTrader: (25)

That is pretty much what i do.