k5383

iTrader: (10)

Im doing a "budget" build... ha

The plan is a lq4/9 in my 84 K5 blazer, I'm wanting to retain the EFI. For simplicity cost effectiveness i'm going to use a corvette filter/regulator.

The questions there enlie what pump should I use? I read somewhere 60 psi minimum? Therefore my holley blue wont work..

Could I use a intank pump from a TBI truck? Or do those not have a high enough psi out put?


Or am I going to need to suck it up and buy a legit nice aftermarket pump?

BMF_Racing

iTrader: (6)

really depends on you HP goals. Alot of people use a intank 255 pump or even two 255's, the second one activated by a hobbs switch at a few psi of boost (if forced induction). TBI pump will not support much HP.

k5383

iTrader: (10)

So with my dreams of a heads cam 6.0 I'll need a better pump..

wantsum410

iTrader: (5)

Walbro 255lph will support 450-500rwh with the right injectors.LS motors require 59psi at the rail.

thewhizkidnumerouno

Not to hi-jack your thread, but I also have a fuel pump question. Will this fuel pump last? http://www.summitracing.com/parts/TFS-25004P/ I have really only heard about Walbro fuel pumps on here. Is it just because they are the most reliable pumps? The pump above puts out more pressure, the same flow and costs $40 less than the Walbro I am thinking about buying. Do I get what I pay for in this instance? Is there any reason I should not run this pump? I do understand that you get what you pay for, but I don't think that a big brand like Trick Flow would put out something that they know is going to immediately fail. Some feedback on this would be greatly appreciated.

CBAR02SLP

I'll share my experience with you...excuse me if I go a little long, but this is a subject close to my heart.

Have a neat '02 SLP vert with a few mods, but my hotrod is a '93 TBIRD SC with a built 32V, Vortech, 6 spd etc, etc...just under 600 RWHP.

I went with an inline Aeromotive Tsunami (supports 700? HP). Everything worked perfectly until the outside ambient went above apprx 90 F. Then the pump with it's speed (yes, I had a speed controller based on RPM), in concert with the tank heat soak from the pavement, would "boil" the fuel, cavitate and shut the car down. Drove Aeromotive crazy (they were great in their support). Chased this problem forever and finally went with an intank Aeromotive 340 (same size as a 255, Weldon has one as well...both excellent...apprx $350). PROBLEM SOLVED!

Of course I thought I was crazy, as did everyone else and then at last year's Power Tour, in FL at 103 ambient, look at the guys pulled over with the exact problem....then to top it off, "Truck You" has a 30 minute show detailing the exact problem!!

Do yourself a favor, spend a couple of extra bucks and go intank at whatever level you need to support your est HP

Good Luck!

i r teh noobz

iTrader: (4)

I run a Walbro 255 on my 5.3 with the Corvette filter.

G-Body

iTrader: (4)

The TBI pump is not going to work at all. I don`t even think it will push enough pressure, but if it did it would not last long.

The walbro 255 is used frequently however, I have heard about them burning out prematurely. From what I read this is caused by the metal rotor vanes that they used. The metal vanes are stronger and flow more than the plastic vanes used in most pumps, but they HATE to be run out of fuel. I read that if the pump hits air even once (IE: low fuel level and then on a corner it hits air) you could possibly wound the pump and get less fuel slow out of it. They are one of the higher flowing pumps out there.

Another popular pump especially if your not going forced induction is the AC Delco EP381. It was used in the mid-late 90`s vortec trucks. You can pick them up for ~50 on the internet. Watch out for generic replacement brand copies though. Some people on a turbo buick board tested several replacement pumps and found that they had a bit less flow than the actual AC Delco brand pump.