EFI High Fuel Pressure

[DwarF]

For you guys running a higher pressure efi setup, did you just put the fuel pump in the fuel line outside of the tank, close to the tank? I have read that you will have flow problems if your tank doesn't have a sump? I am eyeying one of the multipoint systems that require a fuel pressure of 40+psi, and am curious what all beyond the base system I am going to have to get to make it work well.

Thanks in advance,

 

[Hossbaby50]

I have had my TPI running for about 2 months now. I run an MSD pump outside my tank (stock 85 nonbaffle tank). It is mounted to the bottom of the body near the rear tire. It is higher then I would like it but it works for me. No problems yet.

You CAN run a nonbaffle tank. Just don't wheel at high angle with less then 1/4 tank of gas. I have run my truck down to 1/8 tank before and had no real problems. I *think* I did start to strave the pump once at 1/8 tank when I hit a corner real sharp and jumped on the gas. It stuttered for a second then caught. Not sure if it was fuel or not.

Harley

p.s. TPI is a 45PSI system if you didn't know. The MSD pump I run is only $85 shipped from summit or jegs. Works well sofar. it is just really loud. If you have a decent stereo then no worries.

 

[BurbinOR]

Like Harley, I used an external (Bosch in my case) pump for over 2 years in all conditions, all weather and never had a problem. Lots of folks have commented over the years that in-tank is the only way to go, but I went external anyway and never regretted it. Same as a friend of mine, who's now done over 145 TPI conversions, all with external pumps, Bosch and otherwise. 43.5 psi is the pressure TPI 'requires' so I suggest plumbing a new hard line (3/8") and of course you must have a return line (5/16"). I don't recommend using the existing factory hard line/rubber combo for safety reasons.

I too used a non-baffled tank, again without trouble. What I would recommend is getting one tho, from an '87-91 rig just to be on the safe side. Here's a pic of the setup on the K5. The braided stainless covered hose is the return line FYI.

 

[HarryH3]

Another satisfied external pump user here. /forums/images/graemlins/cool.gif Mine's also a Bosch and is very quiet. Harley, do you have yours isolated from the frame? Mine is mounted to a custom bracket that then mounts to the frame via rubber isolators so no vibration is transmitted to the frame rail. The isolators have a rubber center with screw threads sticking out of each end. The original application was as an exhaust system hanger in an old Saab; around 1970 I think. /forums/images/graemlins/cool.gif

 

[Hossbaby50]

Mine is actually mounted to the underside of my body not my frame. It is hire then I would like but is the best place I could find close to the tank because my framerail is cluttered with gas and brake lines. The pump came with mounts that had rubber pads in them to hold the pump. I can't complain. The price was right. I can deal with the whine of the pump. Just turn the stereo up another notch or two.

Harley

 

[dyeager535]

I paid about $35 for a stock high pressure Delco pump for my in-tank TBI sender. If you can get the stock TBI fuel lines off of the same year truck, you might be able to use some or all of it.