Return fuel system ?s

[99COBRA2881]

I'm putting a return style fuel system on my American Iron race car, I'm tired of blowing out frps and dealing with the annoying fuel cutout that the return less system has. I have to shift very slowly or else the damn car cuts out.

I'm not doing this for hp but hoping to cure driveability problems due to the return less system pressure spikes from me constantly being at wot and off the throttle the car never sees part throttle cruise. Warm up laps and cautions being the only exception.

So far my setup is a gss342 pump, -6 supply and -6 return lines.

Is it ok to run the same size supply and return lines?

I'm plumbing it to be a flow through setup that Ys off then goes to the back of each aeromotive rail, fuel goes through the rail to a 180* fitting and flows back to the aeromotive regulator. Then back to the tank.

 

[01yellercobra]

Have you tried having your tuner fix the hesitation? It's not that hard really.

I don't remember you're full engine set up, but it's not stock correct? The -6 should be sufficient since it's the same size as stock. I've heard the larger return line is better because it helps keep the fuel flowing easier and keeps it cooler. I'm no expert on return style, but your system sounds good to me.

 

[99COBRA2881]

Yeah info about the engine would help huh?

Stock cubes, 11:1 compression, ported heads and ported stock intake. Fr500 cams and lt headers. Car put down 372/314 a few years ago. I'm porting on a stock intake now hoping it will square my hp and Tq numbers up closer to how stock flywheel numbers are. 340/337 would be awesome.

I figure the hesitation will be cured once I get the SCT flip chip off the car and use a handheld to tune the car. I'm keeping the frps installed cause I read over at mod fords it helps modulate injector pulse width. Then with the return system I won't be fighting pressure spikes anymore.

Interesting that the return line should be larger that counters my thinking the I should run -8 supply and -6 returns instead of -6 on everything. Keeping the fuel cool is a priority over a 40 minute race.

 

[01yellercobra]

Leaving the FRPS also makes it possible to watch the pressure while datalogging and you can adjust the pressure without having to adjust the tune.

I should have said larger relative what's normally used. As in instead of going -6 feed and -4 return making them both -6. I was going to suggest a -8 feed to the Y block and -6 feeding the rails and a -6 return. IMO the larger lines make it easier for the pump to push the fuel around, which in turn keeps the pump from getting as hot. Which should keep the fuel a little cooler while making it's trip around. This is just my thoughts. I'm no engineer or anything.

 

[99COBRA2881]

I was planning to run -6 on both supply and return. Interesting to know that about adjusting fuel pressure and not the tune.

I'm afraid I'm overthinking this and should just get the sob put together already!

 

[01yellercobra]

I'm sure -6 will be fine for your set up. I was looking into return style but I found out my pumps weren't as maxed as I thought.

But if you don't have the stuff yet I'd have the tune adjusted. I had the shift hesitation even after the PPRV delete. Once I adjusted the pressure in the tune it was fine.

 

[99COBRA2881]

Interesting to know it can be fixed via the tune. Ive already got everything short of a few fittings, just saw the flow through setup the other day and decided to go with that. The other routing I was going to use seemed like it would deliver more fuel to the pass side rail.

With the flow through setup Im planning to Y off to the back of each rail. Even had the thought to use the same length of hose to the pass side rail that I will use to reach the driver side rail. Over thinking but with this car everything has to be overthought and over built.

Just went and looked and lethal supplies -06 line for their budget 4v return system. So -06 it is.