inline fuel pump ???'s
 

i got an '87 silverado with 5.7 tbi, i will be taking the motor/tranny and putting it into my '70. i don't want to have the fuel pump in the tank, so what is the gph and/or psi do i need for an inline pump i can mount on the frame rails? also, what do i do for the internal in the tank? thanks.

Re: inline fuel pump ???'s
 

A 10 psi inline will do the trick.

Re: inline fuel pump ???'s
 

hmmmm, i don't know abouy tbi systems, but that sounds low(10 psi). i've done lots of tpi, and efi, and they always run 35-50 psi with 140 - 190 gph. 10 psi is what i run to my carb. but like i said, i'm not really familar with the tbi system. as for the existing pumps, i left mine in (mainly for the filter) and i see no resitance from pumping through. i have 84 with twin tanks, twin in-line pumps, on a switch(no tank switch) just a fuel check valve(one way flow only) in each line, so i can switch tanks by switching pumps. it's kinda getto, but it does the trick, and matches my getto truck, lol.

Re: inline fuel pump ???'s
 

I believe 10 psi is the norm for tbi. Fuel systems vary on required pressure, many direct fuel injectors require 65+psi, many carbs can run on 6psi, etc. I would actually say that an electric pump in the 25psi range with a quality regulator would be the best route, but a 10 psi in line is commonly used for tbi conversions.

Re: inline fuel pump ???'s
 

Looked it up while I was in the shop earlier, 9-13 psi is what is called for.

Re: inline fuel pump ???'s
 

You need about a 15psi pump with a regulator for TBI.

Re: inline fuel pump ???'s
 

FYI... The stock tbi has a regulator in it. Also why Are you agaist having the fuel pump in the tank... Its really is the best place for it

Graham

Re: inline fuel pump ???'s
 

TBI Fuel Pump

Stock TBI system runs 12 to 15 PSI. You also will need to install return line from TBI injector body back to the gas tank which will require a triple outlet sending unit or alterations with gas tank itself. Be very careful working on gas tanks!!
First outlet is used to draw gas from gas tank, second outlet is used for charcoal canister evaporation control and third outlet used for fuel return. You should not use a dual outlet sending unit since charcoal canister evaporation control line has a built in restriction.
Furthermore, for TBI system to be happy a fuel tank must be equipped with baffles to keep fuel pick-up submerged at all times. Otherwise, TBI would run out of fuel during hard cornering, acceleration or braking. One way to get around un-baffled tanks is to use a small surge fuel tank (about 1/3 Gallon) inline with main gas feed line along with a secondary low pressure pump.

See diagram below for details. I am actually working on this type of conversion for my ‘75 except that I have dual tanks to deal with!!!

TBI (HP Pump) can be found at AZ or ?? Master E8153 or higher performance Carter P5001 (www.summitracing.com) both have similar supply pressure rating 12-20 psi and can supply up to 50GPH.

//RF