Stock fuel system limits
Thread Starter
Racer
Joined: Jun 2012
Posts: 492
Likes: 1
Stock fuel system limits
Aside from injectors, whats a ball park for the limit of power one can make with the stock fuel system on an LS6? I'm talking pumps, lines, rails, and regulator. What about with a boost a pump? I ask because I'm curious if it can handle 500-600whp with simply larger injectors and a good tune and at what point the other components would need upgraded.
AKA "The CLOWN"
Joined: Feb 2010
Posts: 6,261
Likes: 13
From: Chicago South Suburbs
Stock pump and a BAP will hold you to 650 or so, after that, plan on a good secondary fuel system
Melting Slicks
Joined: Jul 2008
Posts: 3,002
Likes: 216
From: Houston Texas
2018 Corvette of Year Finalist
2017 C5 of Year Finalist
Fuel delivery is one of the most important things to pay attention to when pushing for more power.
To be very conservative I would rank it like this for 93 octane fuel:
1. 500 to 525rwhp: No meth, stock fuel system, Hot wire kit, 60# injectors.
2. 525 to 550rwhp: Meth, stock fuel system, Hot wire kit, 60# injectors.
3. 550 to 575rwhp: Meth, stock fuel system, 60# injectors, Hot wire kit, BAP.
4. 575 to 650rwhp: Meth, stock fuel system, 60# injectors, Hot wire kit, BAP, return line, 1:1 regulator.
5. 650 to 700rwhp: Dual Nozzle meth, stock fuel system, 80# injectors, Hot wire kit, BAP, return line, 1:1 regulator.
6. 750+rwhp: Install a secondary fuel pump and correct size injectors.
Notice I recommend an injector change to atleast 80# when trying for 700 rwhp. I also personally wouldn't try to make over 750rwhp without a second fuel pump.
These ranges will depend on many variables such as how much meth you are using, what type of A/F ratio you are trying to achieve, supercharger vs. turbo. It also depends on what type of engine modifications are installed for more air flow.
The list above is very conservative. People have surpassed these values. I'm very conservative and tend to err on the side of too much fuel capacity. It gives you a little bit of cushion in case something happens. Fuel upgrades are usually way cheaper than replacing and engine.
To be very conservative I would rank it like this for 93 octane fuel:
1. 500 to 525rwhp: No meth, stock fuel system, Hot wire kit, 60# injectors.
2. 525 to 550rwhp: Meth, stock fuel system, Hot wire kit, 60# injectors.
3. 550 to 575rwhp: Meth, stock fuel system, 60# injectors, Hot wire kit, BAP.
4. 575 to 650rwhp: Meth, stock fuel system, 60# injectors, Hot wire kit, BAP, return line, 1:1 regulator.
5. 650 to 700rwhp: Dual Nozzle meth, stock fuel system, 80# injectors, Hot wire kit, BAP, return line, 1:1 regulator.
6. 750+rwhp: Install a secondary fuel pump and correct size injectors.
Notice I recommend an injector change to atleast 80# when trying for 700 rwhp. I also personally wouldn't try to make over 750rwhp without a second fuel pump.
These ranges will depend on many variables such as how much meth you are using, what type of A/F ratio you are trying to achieve, supercharger vs. turbo. It also depends on what type of engine modifications are installed for more air flow.
The list above is very conservative. People have surpassed these values. I'm very conservative and tend to err on the side of too much fuel capacity. It gives you a little bit of cushion in case something happens. Fuel upgrades are usually way cheaper than replacing and engine.
Thread Starter
Racer
Joined: Jun 2012
Posts: 492
Likes: 1
With a power level planned to be at or under 600whp, what would be best: a boost-a-pump or a walbro 255? (01 so easy pump swap) Currently also have 72lb injectors. I'll also be adding a hotwire kit. Any real advantage to going to 1:1 at this power level?
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Melting Slicks
Joined: Feb 2006
Posts: 2,163
Likes: 5
From: Houston
Fuel delivery is one of the most important things to pay attention to when pushing for more power.
To be very conservative I would rank it like this for 93 octane fuel:
1. 500 to 525rwhp: No meth, stock fuel system, Hot wire kit, 60# injectors.
2. 525 to 550rwhp: Meth, stock fuel system, Hot wire kit, 60# injectors.
3. 550 to 575rwhp: Meth, stock fuel system, 60# injectors, Hot wire kit, BAP.
4. 575 to 650rwhp: Meth, stock fuel system, 60# injectors, Hot wire kit, BAP, return line, 1:1 regulator.
5. 650 to 700rwhp: Dual Nozzle meth, stock fuel system, 80# injectors, Hot wire kit, BAP, return line, 1:1 regulator.
6. 750+rwhp: Install a secondary fuel pump and correct size injectors.
Notice I recommend an injector change to atleast 80# when trying for 700 rwhp. I also personally wouldn't try to make over 750rwhp without a second fuel pump.
These ranges will depend on many variables such as how much meth you are using, what type of A/F ratio you are trying to achieve, supercharger vs. turbo. It also depends on what type of engine modifications are installed for more air flow.
The list above is very conservative. People have surpassed these values. I'm very conservative and tend to err on the side of too much fuel capacity. It gives you a little bit of cushion in case something happens. Fuel upgrades are usually way cheaper than replacing and engine.
To be very conservative I would rank it like this for 93 octane fuel:
1. 500 to 525rwhp: No meth, stock fuel system, Hot wire kit, 60# injectors.
2. 525 to 550rwhp: Meth, stock fuel system, Hot wire kit, 60# injectors.
3. 550 to 575rwhp: Meth, stock fuel system, 60# injectors, Hot wire kit, BAP.
4. 575 to 650rwhp: Meth, stock fuel system, 60# injectors, Hot wire kit, BAP, return line, 1:1 regulator.
5. 650 to 700rwhp: Dual Nozzle meth, stock fuel system, 80# injectors, Hot wire kit, BAP, return line, 1:1 regulator.
6. 750+rwhp: Install a secondary fuel pump and correct size injectors.
Notice I recommend an injector change to atleast 80# when trying for 700 rwhp. I also personally wouldn't try to make over 750rwhp without a second fuel pump.
These ranges will depend on many variables such as how much meth you are using, what type of A/F ratio you are trying to achieve, supercharger vs. turbo. It also depends on what type of engine modifications are installed for more air flow.
The list above is very conservative. People have surpassed these values. I'm very conservative and tend to err on the side of too much fuel capacity. It gives you a little bit of cushion in case something happens. Fuel upgrades are usually way cheaper than replacing and engine.
I made 750rwhp on a blower setup (more parasitic loss) with AFR in the high 10's using an m10+m15 nozzle without issue. -6an return line, 97-98 rails, kb bap, walbro 255 in tank, and 83# injectors. No sign off issues. I think it would have done 800.
Burning Brakes
Joined: Oct 2004
Posts: 999
Likes: 9
From: Floyds Knobs Indiana
right now mine car is sitting at 707hp with a walbro 400, #60's, BP, and meth. injectors are at 80% and fuel pressure is holding 60psi to red line. some times she drops to 58psi at red line but not often
next fuel system plan is the RSI twin pump, 1:1, and #100 injectors for my e85 system
next fuel system plan is the RSI twin pump, 1:1, and #100 injectors for my e85 system
