Injector size for 355CID @ 450hp+? And other question.
12-02-2005, 10:08 PM
#1
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Injector size for 355CID @ 450hp+? And other question.
What size injectors do I need and do I need to run a higher preasure fuel pump to handle 450-500hp 355CID? Also, I'm having a hard time finding a fuel injected intake that the runners will match up to my Dart Pro 1 cylinder heads. Anyone have any suggestions without having to spend a grand.
Last edited by 1BadZ95; 12-02-2005 at 10:12 PM.
12-02-2005, 11:41 PM
#3
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Re: Injector size for 355CID @ 450hp+? And other question.
I run 30 lb SVO's with my setup. Only at 15 on the pulse width on the injectors at WOT. And I have right at 400 RWHP N/A.
HVY SS
HVY SS
Last edited by hvyss; 12-02-2005 at 11:47 PM.
12-02-2005, 11:46 PM
#4
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Re: Injector size for 355CID @ 450hp+? And other question.
For 500 flywheel HP, you should be running at least a 36# injector. Unless you have a very efficient tune, you will be over 90% duty cycle on a 30# injector, even allowing the 5% extra capacity in the SVO's at 43.5psi fuel pressure.
If you're talking 500rwHP, you'll need the 42's.
If you're talking 500rwHP, you'll need the 42's.
12-04-2005, 12:07 PM
#7
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Re: Injector size for 355CID @ 450hp+? And other question.
Originally Posted by MyShibbyZ28
Here is a good formula for finding out...
lbs/hr = (max HP) x (brake specific fuel consumption) / (no. of injectors)
I think that is right...
ShibbyZ
lbs/hr = (max HP) x (brake specific fuel consumption) / (no. of injectors)
I think that is right...
ShibbyZ
(flywheelHP x BSFC) / (# cylinders x duty cycle)
Example:
(500 HP x 0.46 #/HR/HP) / (8 cyl x .85 DC) = 230 / 6.8 = 33.82 #/HR
A BSFC of 0.46 #/HR/HP would represent a fairly efficient tune. Some sites recommend a BSFC of 0.50 for NA engines and 0.60 for blower and (dry) nitrous engines. 0.50 is a bit conservative.
12-04-2005, 02:21 PM
#9
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Re: Injector size for 355CID @ 450hp+? And other question.
Originally Posted by Injuneer
It's not quite right... it ignores duty cycle.
(flywheelHP x BSFC) / (# cylinders x duty cycle)
Example:
(500 HP x 0.46 #/HR/HP) / (8 cyl x .85 DC) = 230 / 6.8 = 33.82 #/HR
A BSFC of 0.46 #/HR/HP would represent a fairly efficient tune. Some sites recommend a BSFC of 0.50 for NA engines and 0.60 for blower and (dry) nitrous engines. 0.50 is a bit conservative.
(flywheelHP x BSFC) / (# cylinders x duty cycle)
Example:
(500 HP x 0.46 #/HR/HP) / (8 cyl x .85 DC) = 230 / 6.8 = 33.82 #/HR
A BSFC of 0.46 #/HR/HP would represent a fairly efficient tune. Some sites recommend a BSFC of 0.50 for NA engines and 0.60 for blower and (dry) nitrous engines. 0.50 is a bit conservative.
12-04-2005, 06:07 PM
#11
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Location: Hell was full so they sent me to NJ
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Re: Injector size for 355CID @ 450hp+? And other question.
Is your nitrous system wet or dry? You don't need larger injectors for a wet nitrous system. You would size your injectors based on the engine's NA HP. Given the mods you list, you probably should have something larger than a 24# injector..... although I'm not sure a "214/224 comp cam" is "huge".
12-04-2005, 10:23 PM
#13
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Re: Injector size for 355CID @ 450hp+? And other question.
Originally Posted by crAzy95z28
im osrry the cam thats in the new 355 is a 238/242 565/579 lift
What kind of milage did you get with the 210/224?
12-05-2005, 03:01 PM
#15
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Re: Injector size for 355CID @ 450hp+? And other question.
10-12 mile drop from the whole tank? That is like a 1 mpg drop. Good to know what is going to roughly keep the same milage. I plan on doing a 224/224 .525/.525 ZZ409, if those are the right specs....hopefully I'll have some good milage still.