Fuel system plumbing! Which option to choose?

Spectra1

Member
So im trying to decide on the plumbing for my new fuel system and I have come up with multiple options based on my research. I will be running 880 injectors with a single walbro (will likely go bigger injectors and dual walbros in the future) on 91-94 pump gas with water/meth injection. I have come up with 5 options and am pretty sure I know which one I want to go with but I figured I would post them up for more experienced people to discuss just to be sure im not missing something. Look at each pic carefully as each has subtle but important differences. Let me know what you guys think and why. Thanks for having a look.

Dead head with dual feed to rail. For this one I do not want to put a third port in the middle for a return as that would defeat the purpose of this particular design. This is the option im leaning towards.
dualfeeddeadheadfuel_zpsbda00679.png


Dead head system option A
DeadheadfuelOptionA_zps7c5e43da.png


Dead head system option B
DeadheadfuelOptionB_zps91f6fcac.png


Traditional option A
TraditionalOptionB_zps5ea370dc.png


Traditional option B
TraditionalOptionA_zps1f96a626.png
 

phattyduck

New member
I would avoid the dead-head style setups. Fuel at the 'dead' side of the rail/setup would sit in the engine bay and get heated more than necessary. Its a good system for OEMs trying to save money and meet emissions regulations, but not for an ideal performance setup.

Can you do a dual (end) inlet and center outlet to the FPR for the most balanced option? What rail/etc. are you going with?

How big a nitrous shot are you going with? That will also dictate how much of an effect that will have on the fuel flow through the system.

-Charlie
 

Spectra1

Member
I would avoid the dead-head style setups. Fuel at the 'dead' side of the rail/setup would sit in the engine bay and get heated more than necessary. Its a good system for OEMs trying to save money and meet emissions regulations, but not for an ideal performance setup.

I was reading about the dead-head over on mr2oc and it was explained that running 100% of the fuel constantly through the rail would heat it even more and using a dead head would help to keep fuel temps down. They also pointed out the warmer fuel was better at idle and lower rpm and when I opened it up the heated fuel would be used up quickly and cooler fuel would begin to flow. I dont know if I explained that very good but I think you get the point

Can you do a dual (end) inlet and center outlet to the FPR for the most balanced option? What rail/etc. are you going with?.

I have a Hux tffr that is installed and I was trying to avoid having to take it off to drill and tap a center outlet port. I think I will consider this a little more and that may be what I will do. I was kind of hoping for a few more people would weigh in so that I could get a better idea of what would be best.

How big a nitrous shot are you going with? That will also dictate how much of an effect that will have on the fuel flow through the system.

Not a very big one probably on 50-85
 

phattyduck

New member
I assume the main thread you are talking about is this one?

http://www.mr2oc.com/showthread.php?t=298400

I'd lean more towards believing Wolfkatz on these things than RickyB. That said, any of the options would 'work' - which one is the best is the question. I *personally* would lean towards having more constant fuel temps for better tuning consistency - and in my mind that means FPR after the fuel rail. My assumption here is that the pump heats the fuel more than the rail does. If the fuel sits in the rail though (idling, etc.) it can heat up more. I didn't get far enough into the thread to get to any final answers, if they ever got to a consensus.

Let's hear some other opinions!

-Charlie
 

l0ch0w

New member
Option B is probably the cheapest in regards to a non-deadheaded rail because there will be less fittings to purchase...

Deadhead is nice for simplicity's sake, but for initial start-up its kind of a bitch because all of the air in the rail must be evacuated, Id recommend some sort of Schrader type bleeder valve on one end of the rail to let you bleed the air out of the rail before you try to start it up otherwise air bubbles could introduce themselves and create a lean event.

I was also thinking something like this instead of just plugging the end of your rail... this would allow you to bleed air off for initial install or if ever you ran out of gas.

http://www.summitracing.com/parts/ear-2 ... /overview/
 

klue

New member
I run a dead head set up on my car. goes like this Fuel pump- coarse filter- fine filter(oem)- FPR- fuel rail
The return line is obviously off the FPR

Never had any fuel issues, heating issues. My car doesnt make to much butter, but I have used this exact style on customer cars up to 550hp. after that we usually end up running dual pumps, dual feed on the rail and shit gets crazy.

Dead head style is nice because the fuel DOES NOT get heated by circulating through the heat sink of a fuel rail. Only the fuel in the rail gets warm, and its going into the engine anyway.

Dont worry about air getting trapped or lean conditions . Thats all going to be gone once you get the car to run. If your anal make some valve or crack the plug at the end of the rail. All of which I never do, and we stay boosting.

.02
cheers
 

Spectra1

Member
Option B is probably the cheapest in regards to a non-deadheaded rail because there will be less fittings to purchase....

After all the money I have spent on this car cost is really not much of a factor I just want to do it right.

Deadhead is nice for simplicity's sake, but for initial start-up its kind of a bitch because all of the air in the rail must be evacuated, Id recommend some sort of Schrader type bleeder valve on one end of the rail to let you bleed the air out of the rail before you try to start it up otherwise air bubbles could introduce themselves and create a lean event.

I was actually wondering about this. I was not sure if it would be an issue or not

I run a dead head set up on my car. goes like this Fuel pump- coarse filter- fine filter(oem)- FPR- fuel rail
The return line is obviously off the FPR. Never had any fuel issues, heating issues. My car doesnt make to much butter, but I have used this exact style on customer cars up to 550hp. after that we usually end up running dual pumps, dual feed on the rail and shit gets crazy.

Dead head style is nice because the fuel DOES NOT get heated by circulating through the heat sink of a fuel rail. Only the fuel in the rail gets warm, and its going into the engine anyway.

Perfect this is what I was looking for, I can appreciate some real world experience instead of just theory's. I like the sound of dual pumps feeding each side of the rail.....That may be my next move.

Thanks for all your ideas guys, ill post up what I finally end up doing with some pics in the next few weeks when the system is all put together. In the mean time everyone feel free to keep the ideas coming.
 

klue

New member
cheers, but if you dont need dual pumps for your power level dont use them.
your adding heat, points of failure, current draw, and complexity. If hit 500awhp on a single pump. When it goes, the engine wont run and I will know. but if you had dual pumps you probably wont figure it out until its to late

Check out those aeormotive pump controllers. fancy bits,
 
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