Generation IV External Engine - LS2 Fuel rail Max HP?? (do I need aftermarket ruel rails?)




AlterEgo
08-03-2012, 11:19 AM
I was wanting to buy a LS2 fuel rail to compliment my LS2 intake for my project. I and shooting for 700 hp. Will the stock LS2 fuel rail get me enough fuel to my injectors or is it too restrictive for that much HP??

What do you guys recommend??

Here is my setup.. 4.8L, low lift cam, dual springs, LS2 intake, 92MM TB. Everything else stock...


bww3588
08-08-2012, 02:15 AM
If they can feed a heads/cam Ls2/3 etc, I'm sure they can feed a little 4.8.

AlterEgo
08-08-2012, 05:20 AM
Sorry about that, I can't believe I forgot to mention that I am goin to run a 76 or an 88mm turbo with 20lbs of boost! Goal is 700 rwhp..... Will that fuel rail handle all that or are some after market fuel rails gonna be required??


LS1NOVA
08-08-2012, 07:13 AM
Mine has done 700rw at 17lbs of boost on E85 with stock LS1 returnless rails. Ive had it to 22lbs on the street.

gto_ua
08-08-2012, 11:07 AM
I was wanting to buy a LS2 fuel rail to compliment my LS2 intake for my project. I and shooting for 700 hp. Will the stock LS2 fuel rail get me enough fuel to my injectors or is it too restrictive for that much HP??

What do you guys recommend??

Here is my setup.. 4.8L, low lift cam, dual springs, LS2 intake, 92MM TB. Everything else stock...

Better get some aftermarket AN8 fuel rails and build a good return fuel system with boost sourced fuel pressure regulator. In this case you will be 100% sure that if there is some issue(s) its not affiliated with fuel system.

Also it will support like 1000 or more hp if you choose some good pump(s)

AlterEgo
08-09-2012, 07:06 AM
hmmm.. thanks for that info.. so I should be able to use the stock LS2 fuel rail without any issues to begin with...

AlterEgo
08-09-2012, 07:08 AM
Better get some aftermarket AN8 fuel rails and build a good return fuel system with boost sourced fuel pressure regulator. In this case you will be 100% sure that if there is some issue(s) its not affiliated with fuel system.

Also it will support like 1000 or more hp if you choose some good pump(s)

So depending on how much power I will want to run, will determine what fuel rails I will need... I do like the idea of upgrading to a bigger fuel setup to eliminate problems..... What rails would you or anyone recommend?? (fast?)

LS1NOVA
08-09-2012, 07:08 AM
Yes. You didnt mention E85 or gas but your good at that level with either.

AlterEgo
08-09-2012, 09:20 AM
Yes. You didnt mention E85 or gas but your good at that level with either.
I wanted to run E85 because with my turbo but not sure I want to get the 120 or bigger size injectors just to do so..

LS1NOVA
08-09-2012, 03:42 PM
You can get to around 750rw on 95lb injectors or even 80lbers with higher base pressure.

AlterEgo
08-09-2012, 04:05 PM
You can get to around 750rw on 95lb injectors or even 80lbers with higher base pressure.

That will be with regular gas right not with e85?

LS1NOVA
08-09-2012, 04:11 PM
No, with E85.

AlterEgo
08-09-2012, 04:15 PM
No, with E85.

I read somewhere I would need 120 lb injectors to run e85 maybe even larger

AlterEgo
08-09-2012, 04:16 PM
I may need to find more research on how to run e85 and what will be needed...

LS1NOVA
08-09-2012, 04:22 PM
Figure out your max power goals. If you want to just go overkill for 1000rwhp on E85, Id recommend the following:

FIC 160's hi imp
-10 feed, return, and two -8 vents
Fuel rails of choice with Oring boss fittings (not NPT)
Magnafuel regulator
Magnafuel 4303 pump

750rwhp on E85 is kind of the point where things get expensive. Im just over 700 on E with one external Bosch 044 pump, one 255 Walbro, 95 Delhi injectors on 58 base, Aeromotive 13101 reg, stock LS1 rails, -8 feed, -6 return.

DietCoke
08-09-2012, 04:27 PM
I read somewhere I would need 120 lb injectors to run e85 maybe even larger

At 602rwhp I'm only at 47% duty cycle with 1000s @ 7300 rpm (95 LBs) at 58 psi. You wont need injectors that large. I'd go with 850cc/80lbers for a 700rwhp goal.

AlterEgo
08-09-2012, 08:30 PM
Figure out your max power goals. If you want to just go overkill for 1000rwhp on E85, Id recommend the following:

FIC 160's hi imp
-10 feed, return, and two -8 vents
Fuel rails of choice with Oring boss fittings (not NPT)
Magnafuel regulator
Magnafuel 4303 pump

750rwhp on E85 is kind of the point where things get expensive. Im just over 700 on E with one external Bosch 044 pump, one 255 Walbro, 95 Delhi injectors on 58 base, Aeromotive 13101 reg, stock LS1 rails, -8 feed, -6 return.

I dont think I will need 1000rwhp on my street car. I do not want to make a track only car, thats no fun in my eyes.. I want to be able to drive it several hours away from my house and back without any problems, with plenty of power to play around with if needed..

How much more fuel do you burn running e85 vs running regular pump gas? I really do not want to run an external fuel pump due to overheating issues in stop and go traffic.

AlterEgo
08-09-2012, 08:32 PM
At 602rwhp I'm only at 47% duty cycle with 1000s @ 7300 rpm (95 LBs) at 58 psi. You wont need injectors that large. I'd go with 850cc/80lbers for a 700rwhp goal.

how much more fuel do u burn running e85 over pump gas??

I still want my rwhp to reach anywhere in the 700 range.. I will be happy with that.. Nothing more...

409CISecondGen
08-09-2012, 09:17 PM
how much more fuel do u burn running e85 over pump gas??

I still want my rwhp to reach anywhere in the 700 range.. I will be happy with that.. Nothing more...
http://www.injectordynamics.com/HPCalculator.html

Exidous
08-09-2012, 10:55 PM
It's somewhere along the lines on 25-30% more to run E85

LS1NOVA
08-10-2012, 07:40 AM
For your goals, Id use two Aeromotie 340's in the tank, a -8 feed, a boost referenced regulator, the LS2 rails you have, the stock feed as the return, and a good fuel filter such as a big Magnafuel or a Kinsler Monster Mesh.

DietCoke
08-10-2012, 09:57 AM
how much more fuel do u burn running e85 over pump gas??

I still want my rwhp to reach anywhere in the 700 range.. I will be happy with that.. Nothing more...

30-35%. I'm running e85.

AlterEgo
08-10-2012, 10:39 AM
For your goals, Id use two Aeromotie 340's in the tank, a -8 feed, a boost referenced regulator, the LS2 rails you have, the stock feed as the return, and a good fuel filter such as a big Magnafuel or a Kinsler Monster Mesh.

ouch! those aeromotives are $175 each! hope I can find some lightly used... I just bought the aeromotive 13109 regulator.. I hope it will work with it..

now, I gotta find some inexpensive 80lb or 95lb injectors... I wish 60 would be big enough.. I found some on CL for 300 brand new in box. I gotta find a stock feed line, the one I have was cuz pulling the 4.8 out of the donor tahoe.

AlterEgo
08-10-2012, 10:41 AM
30-35%. I'm running e85.

30-35% more fuel! I gotta read up on e85 again to see WHY it is good to run it over pump gas with a boosted motor... GEEZ!! I will be driving gas station to gas station.

DietCoke
08-10-2012, 11:50 AM
Alcohol burns cooler, in addition to the higher octane and larger amount of raw fuel being injected (Again, lowers temps) benefits a boosted motor greatly.

Nasty N8
08-10-2012, 01:45 PM
10.2to1 air fuel for E85 verse 14.7to1 for gas gives about 33% more fuel volume. 700hp will need about 1000hp worth of fuel. Give us a call we can help you spec out your exact system for your needs.

Nasty N8
08-10-2012, 01:54 PM
Oh and to the original question stock fuel rails start to become a restriction about 600whp.