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Mtuned 06-08-2013 05:46 PM

Fuel Rail?
 
Looking for fuel rail options for my gen 6 502.

looked on here, searched google.


The rail only has 1/4 inlet... a little bit of a waste to run -8 line to that restriction. There has to be a better rail out there?


Or can I run two inlets to the rail in the front and back, and use the middle return? Or will this over run the return line? What is everyone else doing?

GPM 06-08-2013 07:29 PM

Is that the fuel rail you were running when the piston melted ?

Mtuned 06-08-2013 08:15 PM

Yes. I am not sure exactly what the deal was, but previous owner said the fuel rail was bored out?

articfriends 06-08-2013 09:05 PM

4 Attachment(s)
I dual fed my stock fuel rail at one point in the middle and the front, couldn't use rear real easy becuase it was so close to dist cap, this worked fine at the 700 or so hp level, my return regulator was close to where the inlet hoses split to feed the rail. Later I built twin rails as hp went up, Smitty

Mtuned 06-08-2013 09:16 PM


Originally Posted by articfriends (Post 3939532)
I dual fed my stock fuel rail at one point in the middle and the front, couldn't use rear real easy becuase it was so close to dist cap, this worked fine at the 700 or so hp level, my return regulator was close to where the inlet hoses split to feed the rail. Later I built twin rails as hp went up, Smitty



I think you and i think the same :) When it comes to fueling i hate cheaping out. You by no chance have another set of rails? or know where i can get some do you? There is no way there is enough volume in stock rail to safely support this 10psi pulley.

Mtuned 06-08-2013 09:21 PM

http://www.ebay.com/itm/8-AN-Fuel-ra...item4173c31d87

Something like this would need to be done?

articfriends 06-08-2013 09:40 PM

1 Attachment(s)

Originally Posted by Mtuned (Post 3939545)
8 An Fuel Rail Blank Extrusion 350mm Long | eBay

Something like this would need to be done?

Thats pretty much what I did, I bought blank rail stock, took a stock rail to a machinist to use to lay out the spacing and took him two pieces which he punched out perfect. I have since built my own small machine shop in back of my business which includes a brideport mill and I plan on doing this kind of stuff myself from here forward but I just recently overextended my mill table and fragged the scale that runs my DRO's and also need to buy a injector boring tool so I couldn't do it in a timely fashion right now or I would hook you up. When I had it done locally though the guy only charged me 80 or a 100$ anyways and I'm sure pretty much any small shop local to you could punch rails, Smitty

Mtuned 06-08-2013 09:46 PM

Right now mods on the boat are:

Stock Comp 509 Block
Nickerson Charger Cam
Ported heads
Valve Job
Roller rockers
Stainless marine EXH
Extrude honed intake manifold
M3 Charger with 6 psi pulley
Intercooled
Mefi4 ECU tuned by AZ speed.

What do you think its making now?

And once i put the 10 PSI pulley on? Im just guessing for fuel needs?

articfriends 06-09-2013 05:40 PM

Lets assume you are making 550hp from the motor itself, going to 14.7 psi of boost would theoretically double the hp minus any friction or resistance it takes to turn supercharger, my guess is it takes about 10 hp or so for every pound of boost to turn your procharger (I was going to actually dyno mine with supercharger pumping air thru enough restriction but disconnected from motor when I did both a N/A tune and blown tune to see what it really took but never did while on the dyno) . Anyways if going to 14.7 psi of booost effectively doubles your hp minus friction then that would be a 550hp gain, so divide that by 14.7= 38 hp per psi of boost. 6 psi of boost would give you a gain of about 228hp, if it took lets say 50 hp to turn the supercharger you would have a net gain of about 175, add that to 550 and puts you at about 725 or so, using the wag method here though becausse we are making a assumption of what your motor makes on its own. If my numbers are correct then 10 psi would give you about 380hp, minus the 100 it took to turn the S/C which is a net gain of about 280,plus 550 would put you around 830 hp. I made 945hp a while back on mine at about 11-12 psi with a 540. I made 1115hp at 14psi or so of boost last time on the dyno, motor made 650 or so on its own, at that rate my numbers are close, 44.2hp per lb of boost x 14= 620 hp gain, 620+ base 650=1270hp, if supercharger took 140 hp to do it would put me at 1130 and I was at 1115 so numbers are somewhat close, Smitty

articfriends 06-09-2013 05:49 PM


Originally Posted by Mtuned (Post 3939552)
Right now mods on the boat are:

Stock Comp 509 Block
Nickerson Charger Cam
Ported heads
Valve Job
Roller rockers
Stainless marine EXH
Extrude honed intake manifold
M3 Charger with 6 psi pulley
Intercooled
Mefi4 ECU tuned by AZ speed.

What do you think its making now?

And once i put the 10 PSI pulley on? Im just guessing for fuel needs?

as far as fuel needs (Injector size) figure your bsfc at .55, max pw at 80% and use about 850hp as your magic number then calulate backwards using one of the online injector calulators like:

https://www.injector.com/injector_selection_guide.php
A 60lb injector turned up in pressure will do it but not much extra margin and your creating problems with fuel pump trying to get good output at a higher pressure
a 80lb injector will easily do it with plenty of extra
a 96lb would have lots of room for growth later BUT you start getting the pw pretty short to get it to idle at all
The Siemans/Deka injectors have proven themselves to be about the best high impedance injector out there and guys have ran them to as much as 100 psi supply without them acting up which is just about unheard of with most injectors, Smitty

GPM 06-09-2013 06:52 PM


Originally Posted by articfriends (Post 3939788)
Lets assume you are making 550hp from the motor itself, going to 14.7 psi of boost would theoretically double the hp minus any friction or resistance it takes to turn supercharger, my guess is it takes about 10 hp or so for every pound of boost to turn your procharger (I was going to actually dyno mine with supercharger pumping air thru enough restriction but disconnected from motor when I did both a N/A tune and blown tune to see what it really took but never did while on the dyno) . Anyways if going to 14.7 psi of booost effectively doubles your hp minus friction then that would be a 550hp gain, so divide that by 14.7= 38 hp per psi of boost. 6 psi of boost would give you a gain of about 228hp, if it took lets say 50 hp to turn the supercharger you would have a net gain of about 175, add that to 550 and puts you at about 725 or so, using the wag method here though becausse we are making a assumption of what your motor makes on its own. If my numbers are correct then 10 psi would give you about 380hp, minus the 100 it took to turn the S/C which is a net gain of about 280,plus 550 would put you around 830 hp. I made 945hp a while back on mine at about 11-12 psi with a 540. I made 1115hp at 14psi or so of boost last time on the dyno, motor made 650 or so on its own, at that rate my numbers are close, 44.2hp per lb of boost x 14= 620 hp gain, 620+ base 650=1270hp, if supercharger took 140 hp to do it would put me at 1130 and I was at 1115 so numbers are somewhat close, Smitty

How much fuel were you burning at 1115 hp ?

articfriends 06-09-2013 07:15 PM


Originally Posted by GPM (Post 3939804)
How much fuel were you burning at 1115 hp ?

No return fuel meter on Crocketts dyno to measure fuel and calculate bsfc when running efi back then but if I was doing it today I would just return extra back to pump suction while dynoing and put meter on pump suction but I did not think of it then, Smitty

Mtuned 06-09-2013 07:25 PM

Ordered fuel rail stock today! Hopefully it ships tomorrow. Will post up pics once finished :)

GPM 06-09-2013 07:37 PM


Originally Posted by articfriends (Post 3939812)
No return fuel meter on Crocketts dyno to measure fuel and calculate bsfc when running efi back then but if I was doing it today I would just return extra back to pump suction while dynoing and put meter on pump suction but I did not think of it then, Smitty

Just curious, did you do any data logs on the dyno, what size injector, what pulse width at peak torque ?


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