Fuel Rail modd questions
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Posts: 1,462
From: smog zone adjacent to a great lake
Re: Fuel Rail modd questions
Originally Posted by Injuneer
(I know you have the details on my system, but let me repeat them) I run a -6AN discharge line from each of two Bosch pumps, through an NOS -6AN "Y", into a single -6AN line to an SX billet fuel filter, then a -6AN line from the filter to the back of the engine. There is splits through another NOS -6AN "Y" into a -6AN line into the back of each rail. The return comes off a -6AN fitting welded to the diagonal cross-over pipe, with a -6AN return line back to a Weldon AFPR under the cowl, then a -6AN line back to the tank. This system is proven to support an 800flywheelHP engine, running a 300-shot of dry nitrous.
=============
What should I look for in a FPR?
****Look at the Weldon..... it is expensive, but reliable.
==============
What is the best method for seting up the FPR?
A. Have it REG the press prior to a Y block then running it to both sides of the rail. This would keep the heat of the ENG off the return fuel
****That is a "dead-ended" system, as used in the LS1 fuel system looks like.
=============
What should I look for in a FPR?
****Look at the Weldon..... it is expensive, but reliable.
==============
What is the best method for seting up the FPR?
A. Have it REG the press prior to a Y block then running it to both sides of the rail. This would keep the heat of the ENG off the return fuel
****That is a "dead-ended" system, as used in the LS1 fuel system looks like.
Fred, I didn't realize 'dead ended'ystem had a line back to the tank (from regulator).What is the best method for seting up the FPR?
A. Have it REG the press prior to a Y block then running it to both sides of the rail. This would keep the heat of the ENG off the return fuel
A better way, but not worth enuf extra, to change your setup for, I take?
Last edited by arnie; Aug 7, 2004 at 08:16 PM.
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Joined: Oct 2001
Posts: 1,462
From: smog zone adjacent to a great lake
Re: Fuel Rail modd questions
Originally Posted by mongse_1
This is what I ran...
Feed:
-10AN line to a Barry Grant y-block in the engine bay
-dual -8AN to fittings on the back of the rail
-dual -8AN returns to a Weldon regulator
-single -6AN return to tank
Feed:
-10AN line to a Barry Grant y-block in the engine bay
-dual -8AN to fittings on the back of the rail
-dual -8AN returns to a Weldon regulator
-single -6AN return to tank
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Joined: Nov 1998
Posts: 71,094
From: Hell was full so they sent me to NJ
Re: Fuel Rail modd questions
Originally Posted by arnie
That is a "dead-ended" system, as used in the LS1 fuel system looks like.
Fred, I didn't realize 'dead ended'ystem had a line back to the tank (from regulator).
Fred, I didn't realize 'dead ended'ystem had a line back to the tank (from regulator).A dead-end system uses a "bypass" type pressure relief valve (regulator) and dumps the excess back to the tank. In the LS1 cars (97 C5 is an exception) the bypass type regulator just happens to already be in the fuel tank, so it doesn't need a return line, it just "dumps" into the tank. But if you build a "bypass" style, dead end system, the regulator dumps the excess into a return line, without having it pass through the rails first.
Thread Starter
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Joined: Jul 2001
Posts: 310
From: California
Re: Fuel Rail modd questions
And that was my first intention until I read the direction for the AFPR. It does not have any option for installing it. Diagram shows one return outlet and two return inlets from the fuel rail. I sent them an e-mail asking if I could route it differently and got no reply.
Thread Starter
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Joined: Jul 2001
Posts: 310
From: California
Re: Fuel Rail modd questions
I ordered a set of Earyl's -6an to -10 AN reducer and it is not even close to fitting into the rail on my 4th Gen LT1. I went to the local speed shop and found -6 to -8AN reducers will fit with a little grinding or lath work, if you have one.
I found that the XRP fittings blue is darker than both Aero's and earlys fittings. I like the dark blue a lot better. And some of the fitting are cheeper than Jegs.
I found that the XRP fittings blue is darker than both Aero's and earlys fittings. I like the dark blue a lot better. And some of the fitting are cheeper than Jegs.
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Joined: Jul 2002
Posts: 292
From: Philly, PA
Re: Fuel Rail modd questions
Hows the install going? I just got my 30# injectors, and I am still debating what setup I want to do....Edelbrock for $79 has rails with 8AN fittings already in, I am most likely going to step that down to 6AN....put some pics up then when you get a chance!
good luck
good luck
Thread Starter
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Posts: 310
From: California
Re: Fuel Rail modd questions
I went to a shop today to see about cutting the ends of the rail off and open up the ends. They wanted too much money for the work. I know a few guys with a band saw so I will try and make the cuts myself for free. I think it would be a lot easier to buy rails that already have the fittings. It would also be cool to have both rails the same size. I may have to look into that for ease of maintenance and looks.
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Posts: 784
Re: Fuel Rail modd questions
Unless you plan on making well over 650RWHP the mods in this thread are expensive and overkill.
A single Racetronix in-tank pump system, BAP and adjustable FPR are more than enough for most sane street HP levels.
A single Racetronix in-tank pump system, BAP and adjustable FPR are more than enough for most sane street HP levels.
Thread Starter
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Posts: 310
From: California
Re: Fuel Rail modd questions
You are correct. It is expensive and over kill. But it looks cool and it eliminates the fuel leak from the schrader valve test port I have. It may also help keep my fule press the same on both side of the rail.
Speaking of rails, do you guys make and sell fuel rails?
I alsredy have your LT1 series 2 kit.
Oh before I forget. I once e-mailed you guys about blowing a 20Amp fuse when on the dyno. I found that the wire that runs down behind the alternator came in contact with the #2 primary on the header and shorted/melted the wire. I'm sure it will work fine once I repair the wire and route it else where.
Speaking of rails, do you guys make and sell fuel rails?
I alsredy have your LT1 series 2 kit.
Oh before I forget. I once e-mailed you guys about blowing a 20Amp fuse when on the dyno. I found that the wire that runs down behind the alternator came in contact with the #2 primary on the header and shorted/melted the wire. I'm sure it will work fine once I repair the wire and route it else where.
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Joined: Oct 2001
Posts: 784
Re: Fuel Rail modd questions
Originally Posted by supermo26
You are correct. It is expensive and over kill. But it looks cool and it eliminates the fuel leak from the schrader valve test port I have. It may also help keep my fule press the same on both side of the rail.
Speaking of rails, do you guys make and sell fuel rails?
I alsredy have your LT1 series 2 kit.
Oh before I forget. I once e-mailed you guys about blowing a 20Amp fuse when on the dyno. I found that the wire that runs down behind the alternator came in contact with the #2 primary on the header and shorted/melted the wire. I'm sure it will work fine once I repair the wire and route it else where.
Speaking of rails, do you guys make and sell fuel rails?
I alsredy have your LT1 series 2 kit.
Oh before I forget. I once e-mailed you guys about blowing a 20Amp fuse when on the dyno. I found that the wire that runs down behind the alternator came in contact with the #2 primary on the header and shorted/melted the wire. I'm sure it will work fine once I repair the wire and route it else where.
An imbalance on the F-LT1 rails is not usually a factor unless you are making big HP.
We do not make / sell pre-made rails.
Good to hear you found your problem with the harness. Make sure you solder the connection if required and cover it with heatshrink. This will help prevent future problems.
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From: Hell was full so they sent me to NJ
Re: Fuel Rail modd questions
Originally Posted by Racetronix
Unless you plan on making well over 650RWHP the mods in this thread are expensive and overkill.
A single Racetronix in-tank pump system, BAP and adjustable FPR are more than enough for most sane street HP levels.
A single Racetronix in-tank pump system, BAP and adjustable FPR are more than enough for most sane street HP levels.
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From: Buffalo, New York
Re: Fuel Rail modd questions
Originally Posted by Injuneer
The LT1's I described are/were making anywhere from 800flywheelHP (my lowly nitrous stroker) to 1,125flywheelHP. I really don't think "RWHP" is the proper way to size fuel systems, since the fuel requirements would vary extensively from a manual trans "all motor" setup, to a power adder engine running a TH400 and a very loose convertor. Feel free to disagree
Rich
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Joined: Oct 2001
Posts: 784
Re: Fuel Rail modd questions
Most people are running the 700.
Since most tuners use a chassis dyno it is easier for customers to relate to these numbers.
Most people have no idea what their true FWHP is.
Either way a 15-20% loss is pretty standard.
Quoting these numbers works for 99% of our customers.
There are very few people who are in the 800RWHP range and this is not a market we generally cater to.
We receive daily inquiries from people who supply a shopping list of go fast parts asking us what fuel system to use.
Sometimes they quote pie in the sky HP numbers. (ie motor 400HP + blower 200HP + N2O 200HP = 800HP.... NOT!)
Some people have no clue what their HP will be.
The reality is that many people rarely come even close to their inflated HP numbers and that the Racetronix single in-tank system is more than enough for them.
Since most tuners use a chassis dyno it is easier for customers to relate to these numbers.
Most people have no idea what their true FWHP is.
Either way a 15-20% loss is pretty standard.
Quoting these numbers works for 99% of our customers.
There are very few people who are in the 800RWHP range and this is not a market we generally cater to.
We receive daily inquiries from people who supply a shopping list of go fast parts asking us what fuel system to use.
Sometimes they quote pie in the sky HP numbers. (ie motor 400HP + blower 200HP + N2O 200HP = 800HP.... NOT!)
Some people have no clue what their HP will be.
The reality is that many people rarely come even close to their inflated HP numbers and that the Racetronix single in-tank system is more than enough for them.
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Joined: Dec 1999
Posts: 53
Re: Fuel Rail modd questions
quick comment with using a dead-ended setup...by running the FP before the fuel rails and letting the excess bleed off before it goes to the engine can cause vapor lockup. I've seen it first hand. When running normal slow bumper to bumper driving, the excess fuel bled back to the tank continues...the fuel sits in the rails until it's used up, it can heat up and boil on hot days since it's just sitting there waiting to be used...not enough cool fuel enters to keep it cool.
The stock setup runs the fuel through one rail out the other then through the FP to keep constant flow...it can heat up your fuel overall though you may have less issue with vapor lock.
J
The stock setup runs the fuel through one rail out the other then through the FP to keep constant flow...it can heat up your fuel overall though you may have less issue with vapor lock.
J
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Joined: Jun 2000
Posts: 1,542
From: Long Island, NY ; Norfolk, VA
Re: Fuel Rail modd questions
I said fug it and went w/a entire weldon sys. Their pump, regulator, and dial a flow. It was friggin' expensive.. Youngs Performance Makes' a really nice machined y block.. I picked one of those up as well.. I"ll be running a dual feed setup on my lowly 355..
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