HELP....stupid question.
Thread Starter
Melting Slicks
Joined: Jun 2004
Posts: 3,413
Likes: 278
From: NC
HELP....stupid question.
Friend of mine has a 402 stroker built and it made 517 rwhp and 465 tq down south at 4 to 5 thousand ft above sea level.
Got it to a dyno today here in NC and it made considerable less hp.... 489/442 running really lean up top so we couldn't spray the 150 shot.
My question is simple... how much hp can the stock injectors support NA?
I thought the stock injectors were good up to 500 rwhp and am wondering how the builder/ tuner of the 402 got 517 rwhp????? Not sure wether to call
or maybe the higher altitude helped the stock injectors....
His car was running real lean from the mail order tune that he got from the motor builder. His initial tune was very rich while he was breaking in the motor. Just trying to figure out how to get him back up to his original numbers......
Thanks guys....
Got it to a dyno today here in NC and it made considerable less hp.... 489/442 running really lean up top so we couldn't spray the 150 shot.
My question is simple... how much hp can the stock injectors support NA?
I thought the stock injectors were good up to 500 rwhp and am wondering how the builder/ tuner of the 402 got 517 rwhp????? Not sure wether to call
or maybe the higher altitude helped the stock injectors....His car was running real lean from the mail order tune that he got from the motor builder. His initial tune was very rich while he was breaking in the motor. Just trying to figure out how to get him back up to his original numbers......
Thanks guys....
Team Owner
Joined: Jul 2002
Posts: 36,985
Likes: 68
From: This city NEVER sleeps! Frank's back yard!
Originally Posted by nextphasemarko
NA hp is different than FI hp (from what i have heard)..... I made just over 500 rwhp w/ my h/c procharger and needed larger injectors.....
Anyone else?
Anyone else?
Melting Slicks
Joined: Mar 2002
Posts: 2,931
Likes: 2
From: Tx
Originally Posted by DDSLT5
hp is hp. fuel is fuel. The stock injectors can only deliver so much of it, N/A or no.
As an example
27lb injectors will get you to 500 na rwhp. Under FI, you would need 37lb.
Here is a worksheet with some formulas you can usehttp://www.rceng.com/technical.htm
One more thing, the heat of the fuel can have a big impact on the fuel pressure and the pump. I would start with the pump and worry about the injectors if the duty cycle goes to high.
I don't know what blows up more FI ls1s, hot fuel related pressure issues or oil from an improperly setup PCV.
Last edited by QuickSilver2002; Feb 3, 2006 at 12:22 AM.
Melting Slicks
Joined: Apr 2005
Posts: 3,418
Likes: 1
From: Chicagoland Area IL
Originally Posted by QuickSilver2002
Not true. The BSFC (Brake specific fuel consumption) is much higher on FI engines. The reasons for this are pretty obvious if you think about it, unless you can come up with that "free power" fi system (it would have to be driven externally).
As an example
27lb injectors will get you to 500 na rwhp. Under FI, you would need 37lb.
Here is a worksheet with some formulas you can usehttp://www.rceng.com/technical.htm
One more thing, the heat of the fuel can have a big impact on the fuel pressure and the pump. I would start with the pump and worry about the injectors if the duty cycle goes to high.
I don't know what blows up more FI ls1s, hot fuel related pressure issues or oil from an improperly setup PCV.
As an example
27lb injectors will get you to 500 na rwhp. Under FI, you would need 37lb.
Here is a worksheet with some formulas you can usehttp://www.rceng.com/technical.htm
One more thing, the heat of the fuel can have a big impact on the fuel pressure and the pump. I would start with the pump and worry about the injectors if the duty cycle goes to high.
I don't know what blows up more FI ls1s, hot fuel related pressure issues or oil from an improperly setup PCV.
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Team Owner
Joined: Jul 2002
Posts: 36,985
Likes: 68
From: This city NEVER sleeps! Frank's back yard!
Originally Posted by QuickSilver2002
Not true. The BSFC (Brake specific fuel consumption) is much higher on FI engines. The reasons for this are pretty obvious if you think about it, unless you can come up with that "free power" fi system (it would have to be driven externally).
As an example
27lb injectors will get you to 500 na rwhp. Under FI, you would need 37lb.
Here is a worksheet with some formulas you can usehttp://www.rceng.com/technical.htm
One more thing, the heat of the fuel can have a big impact on the fuel pressure and the pump. I would start with the pump and worry about the injectors if the duty cycle goes to high.
I don't know what blows up more FI ls1s, hot fuel related pressure issues or oil from an improperly setup PCV.
As an example
27lb injectors will get you to 500 na rwhp. Under FI, you would need 37lb.
Here is a worksheet with some formulas you can usehttp://www.rceng.com/technical.htm
One more thing, the heat of the fuel can have a big impact on the fuel pressure and the pump. I would start with the pump and worry about the injectors if the duty cycle goes to high.
I don't know what blows up more FI ls1s, hot fuel related pressure issues or oil from an improperly setup PCV.
Hm. Interesting.
Racer
Joined: Sep 2005
Posts: 341
Likes: 2
That is great information regarding an FI engine's increased fuel needs, BUT I still can't believe that his engine, producing about 600hp (517 at the wheels), is able to run at WOT with stock injectors.
I would have thought stock injectors would go static way before the 600hp mark!
Learn something new everyday I guess
Tommy
I would have thought stock injectors would go static way before the 600hp mark!
Learn something new everyday I guess
Tommy