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Discussion Starter #1
I am trying to figure out the best way to set up my fuel system:

Scenerio #1:
HKS fuel rail, -6 line on one side from one of the fuel pumps, -6 line on another side from the other fuel pump and a -6 return line fromt he center of the rail (I know this is offset) to the regulator.

Scenerio #2:
HKS fuel rail, -8 line on one side from both fuel pumps, center (I know this is offset) capped off and then a -6 on the other side of the rail going to the regulator. I was told this might be good because of the turbulence that might get caused from doing it the other way.

If there are any other suggestions on the setup, please post it. Thanks for all the input.
 
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#1 seems to be the standard Supra community fuel set-up. it works. Its simple to do.

#2 has NOT been widely used and people tend to shy away from the unknow, although I am using it, but with a -8 into the fuel pressure regulator, then just connecting into the factory return.

H.
 

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Discussion Starter #3
MACH1nTTcoupe said:
#1 seems to be the standard Supra community fuel set-up. it works. Its simple to do.

#2 has NOT been widely used and people tend to shy away from the unknow, although I am using it, but with a -8 into the fuel pressure regulator, then just connecting into the factory return.

H.

Do you think that you could get away with a -6 into the regulator since your return line isn't a -8?

Do you happen to know the exact size of the stock lines?

Have you ever had any idle problems with the way you have yours done or anything like that and are you running single turbo?
 

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I have the same set up as option #2. The only difference is that I have -8 into the fuel filter then a -6 out of the fuel filter into one end of the fuel rail. I figured that there would be some pressure drop across the fuel filter anyway. The other end of the rail goes to the fuel pressure regulator then goes to the stock return line. This configuration is prety simple with minial number of AN hose ends. Good luck.
 
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Do you think that you could get away with a -6 into the regulator since your return line isn't a -8? YES

Do you happen to know the exact size of the stock lines? I think its METRIC, but just about smaller then -6AN

Have you ever had any idle problems with the way you have yours done or anything like that and are you running single turbo?

No IDLING problems and I have the SP63 turbo/ cast manifold

H.
 
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I run #1 setup. Whatever you do, don't "T" feeds off both pumps together inside the tank, that defeats the purpose. Run line directly from each pump to each end of the rail, from center return to regulator, then use stock return line from there. Keep all the tank vent lines and stuff too.

Do you guys draw power (12v, IGN) off the factory gas tank harness, or all the way from the front of the car (battery - w/inline fuse, ECU harness)? Just wondering how you do your wiring......i run latching relay in the back, 30Amp Bosch, and have been debating running power directly off battery.
 
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that is true, the "T" defeats the purpose, inside or outside the tank... I run the # 2 set-up that was mentioned , 2 pumps in tank, 2 new 3/8 lines out (-6AN) , THEN into a -6 Y block and -8 out into 1 Paxton fuel filter, then into the back of the HKS rail.

I am also working on a fuel bracket where the Y will be inside the tank , and will have only one -8 line out into the filter.

H.
 
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MONSTER said:
I run #1 setup. Whatever you do, don't "T" feeds off both pumps together inside the tank, that defeats the purpose. Run line directly from each pump to each end of the rail, from center return to regulator, then use stock return line from there. Keep all the tank vent lines and stuff too.

Do you guys draw power (12v, IGN) off the factory gas tank harness, or all the way from the front of the car (battery - w/inline fuse, ECU harness)? Just wondering how you do your wiring......i run latching relay in the back, 30Amp Bosch, and have been debating running power directly off battery.
I run 2 10gauge wires from the battery to 2 Bosch relays. I get the relay signal from the factory harness. 12volt mod done...

Monster,
Remember me from TwinTurbo.net?
You tried to buy my Nismo 555 inj from me..
I'm not sure if I asked you that before, but good to see you on this forum...

BTW, MachTwinTT (aka Henry, aka IG) is the man w/fuel systems, and his upgraded fuel pump brackets are second to none.. Highly recommended...
 
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Whats up Roberto, of course I remember you. I see you even kept your old screen name :)

Thanks for the wiring tips, I am not sure how to do that, since I hate doing electrical shit myself. Could you email me your number or something to [email protected] and I'll call you to get some details on this? Or if you feel like, you can post details here, so others interested can benefit too.

I had my in-tank pump setup done by Mike Sweintek (SA, TX), and god fuckin damn, it looks like it came like that from the factory. He is helping me tune the car as well. Guy is amazing.
 

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Discussion Starter #10
MACH1nTTcoupe said:
that is true, the "T" defeats the purpose, inside or outside the tank... I run the # 2 set-up that was mentioned , 2 pumps in tank, 2 new 3/8 lines out (-6AN) , THEN into a -6 Y block and -8 out into 1 Paxton fuel filter, then into the back of the HKS rail.

I am also working on a fuel bracket where the Y will be inside the tank , and will have only one -8 line out into the filter.

H.
I have one question on this:

Why would you do a -8 out when the HKS fuel rail is a -6 all the way through? I think that the SP fuel rail is a -8...are you keeping in mind that you might upgrade sometime?
 
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I'm thinking about running a -10 line(getting a fuel cell with -10 fittings) and running it to one end of the rail and a -6 line out the other side of the rail and back to the cell. Hopefully that'll work out well. I guess we'll see.......
 

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I just ordered SPs rail. The threads are 3/8" NPT with a 3/8 to -6 connector. Easy to find a 3/8 to -8 if you want that instead. That's what I'm doing.
 

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Discussion Starter #13
supra400hptt said:
I just ordered SPs rail. The threads are 3/8" NPT with a 3/8 to -6 connector. Easy to find a 3/8 to -8 if you want that instead. That's what I'm doing.
How much did the rail cost you?
 

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I got the rail, 750cc injectors, o rings and injector clips for $900. Saved about $100 over the HKS, greddy 720cc. PHR has this for $999. I really wanted -8 at the feed and from what I've read trying to get the right fitting for the HKS rail is almost impossible. I guess it has weird threads. The SP uses 3/8 NPT like I wrote earlier. Easy to put what ever dash size you want since these fittings are very common. I'm using -8 going up, dual walbros and -6 back to the stock filter. Rest of the way back I'm using the stock feed line since it's almost -6 in size. Should be plenty big for the return flow and easier since the fittings already go into the tank. Will only need to install a -8 bulkhead fitting in the tank cover and the necessary electrical. I'm doing a simple, in one end and out the other. The SP does have a center return if you want to go that route. And from what I've been told, the HKS has a center return but it comes out between 5 and 6. Not really a center. I believe it's not necessary to feed both ends if the system is a good design. But before I upset someone since a lot of people go this route, it can't hurt anything. I just didn't want the extra complication. I plan to stay below 600rwhp and the normal in/out has been sufficient for a lot of high hp cars using 720cc injectors. If I was going 700 or more I'd probably do a dual feed. Which at that point bigger injectors would probably be needed.
 

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Anyone running a PHR Stage 1 or 2 Fuel system? How do you like it? I'm in the process of buying a PHR Stage 1 Single Turbo Kit from Dusty at MVP and will eventually go to Stage 2 as soon as I decide on a fuel system. How does SP and PHR compare? Hope someone can answer these questions.
 

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Discussion Starter #16
supra400hptt said:
I got the rail, 750cc injectors, o rings and injector clips for $900. Saved about $100 over the HKS, greddy 720cc. PHR has this for $999. I really wanted -8 at the feed and from what I've read trying to get the right fitting for the HKS rail is almost impossible. I guess it has weird threads. The SP uses 3/8 NPT like I wrote earlier. Easy to put what ever dash size you want since these fittings are very common. I'm using -8 going up, dual walbros and -6 back to the stock filter. Rest of the way back I'm using the stock feed line since it's almost -6 in size. Should be plenty big for the return flow and easier since the fittings already go into the tank. Will only need to install a -8 bulkhead fitting in the tank cover and the necessary electrical. I'm doing a simple, in one end and out the other. The SP does have a center return if you want to go that route. And from what I've been told, the HKS has a center return but it comes out between 5 and 6. Not really a center. I believe it's not necessary to feed both ends if the system is a good design. But before I upset someone since a lot of people go this route, it can't hurt anything. I just didn't want the extra complication. I plan to stay below 600rwhp and the normal in/out has been sufficient for a lot of high hp cars using 720cc injectors. If I was going 700 or more I'd probably do a dual feed. Which at that point bigger injectors would probably be needed.
Are those the Accel injectors you have? If so, do you know what the part number is?
 
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Tony,
about that HKS rail having a -6 fittings is true, I had the rail widened and welded -8 fitting on both ends of the rail.

H.
 

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>Are those the Accel injectors you have? If so, do you know what the part number is?

Not sure which injectors. I just trusted Larry at SP that what he is selling is good. They are 750cc he said. I'll post as soon as they get here.
 

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Discussion Starter #19
MACH1nTTcoupe said:
Tony,
about that HKS rail having a -6 fittings is true, I had the rail widened and welded -8 fitting on both ends of the rail.

H.
Did you widen it because you thought that you would not have enough fuel flow through the -6? Do you happen to know what the max hp is through the HKS fuel rail without doing anything to it? Thanks for your help...it is very appreciated.
 
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The only reason that I had it widened is so I could do the -8 fuel line. And, I only had the ends widened so I could use the new -8AN fitting, otherwise the rest of the internals stayed untouched. the rail looks wide enought to support the power combo of the 720cc injectors.
It is also possible to replace the -6AN fittings with -8AN that come on the HKS rail, I just didnt want to wait a month to have them. Paisley might sell them (some metric fitting to -8AN that I needed).

H.F.
 
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