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I got a 88LX witha 91 HO engine with a F303 cam,GT40P intake,performer RPM heads,and a powerdyne supercharger I was wondering what injector size and MAF I need the use?
 
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UMMMMMMMMMMMMMMMMM......

Doesn't injector size have a little to with the horsepower being produce by the engine......

I read that somewhere.....:)
 

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Hey OP how much you boosting and what else do you have done to your fuel system?
 

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42's are good for about 435hp @ 85% with forced induction(flywheel)..
so even though he has an alphabet cam:kooky:, the rest of the combo with 6-8psi should easily be in the 400hp+ area at the flywheel
 

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UMMMMMMMMMMMMMMMMM......

Doesn't injector size have a little to with the horsepower being produce by the engine......

I read that somewhere.....:)


He gave us everything we needed to know. We know its a stock block so hes not runnin over 500hp especially with that intake. SO that leaves him somewhere from 5-12# of boost which could vary from 36# inj to 42# inj but anyone with boost is gonna want more so 42# inj was the final answer:smartass:
 
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hmm..our sources seem to differ..i was going by this chart(scroll down a bit):

http://www.fordracingparts.com/download/charts/Fuel_Injectors_and_Adaptors.pdf

i'll agree with your chart for an N/A application though

Doesn't matter flywheel horsepower is flywheel horse power......

He gave us everything we needed to know. We know its a stock block so hes not runnin over 500hp especially with that intake. SO that leaves him somewhere from 5-12# of boost which could vary from 36# inj to 42# inj but anyone with boost is gonna want more so 42# inj was the final answer:smartass:
Ok what if he is using a FMU.......:?:

Just for the record for those who don't know me......

I know the answer to the questions that are being asked.....

I just get a perverted pleasure out of making these guys think.......:smartass:
 

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I just get a perverted pleasure out of making these guys think.......:smartass:
That is something Jay Allen would say. And back to the OP.... I got a friend with 42's and runs a vortech with the TFS top end and puts to the wheels on a stock block in the 430 range on a very safe tune and around 500 lbs of torque. This is with a custom tune burned just for him at around 10 lbs of boost.
 

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max safe hp = [ (injector size) x (total # of injectors) x (max duty cycle) ]/BSFC

The following guide is a general rule of thumb for sizing fuel injectors on an 8-cylinder engine using a BSFC of 0.50. Forced-induction engines
typically range from a BSFC of 0.55 to 0.65
, with the latter value arising from the fuel enrichment necessary to keep exhaust temperatures below 1650 deg F
and catalyst temperatures below 1700 deg F.
Naturally Aspirated: (19 lb x 8 x .85)/.50 = 258.4 or approx 258 hp @ 85% duty cycle
Forced Induction @ 0.55: (19 lb x 8 x .85)/.55 = 234.9 or approx 235 hp @ 85% duty cycle
Forced Induction @ 0.65: (19 lb x 8 x .85)/.65 = 198.8 or approx 199 hp @ 85% duty cycle
...........................

Note that at WOT, the fuel pump in the forced-induction engine must supply fuel at a higher pressure
than in the naturally aspirated engine. As mentioned in the previous section, this means that the fuel pump supplying the forced-induction engine will have a
lower maximum flow rate capability than the fuel pump supplying the naturally aspirated engine. This is a critical concept to grasp because it means that in
general, for engines with equal brake horsepower, the fuel pump supplying the forced-induction engine will need to have more capacity than the
fuel pump supplying the naturally aspirated engine!
 

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Doesn't matter flywheel horsepower is flywheel horse power......



Ok what if he is using a FMU.......:?:

Just for the record for those who don't know me......

I know the answer to the questions that are being asked.....

I just get a perverted pleasure out of making these guys think.......:smartass:

If he was using an FMU he would not be asking about the injector size to use cause the FMU would be calibrated for the injectors he MUST use.:smartass:
 
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I just get a perverted pleasure out of making these guys think.......:smartass:


That is something Jay Allen would say. And back to the OP.... I got a friend with 42's and runs a vortech with the TFS top end and puts to the wheels on a stock block in the 430 range on a very safe tune and around 500 lbs of torque. This is with a custom tune burned just for him at around 10 lbs of boost.
If he was using an FMU he would not be asking about the injector size to use cause the FMU would be calibrated for the injectors he MUST use.:smartass:

But it is working you guys are thinking and doing a fine job......

Every so often the old man tries to inspire others......:)
 

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But it is working you guys are thinking and doing a fine job......

Every so often the old man tries to inspire others......:)

Well thats what makes this place work so well. :) But right now you need to send that inspiration toward the computer techs cause the slow/mis-haps are really getting old:waveyLOL
 
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