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Injector formula is:

(bhp x bsfc) / (No. injectors x DC)

bhp = peak crank horsepower (note this is PEAK power at crank not whp, not average, etc.)

bsfc = which is the 'brake specific fuel consumption"; basically .50 for blown engines, .45 for NA

No. of injectors is 4 for most of us

DC = duty cycle which should be .85

so...

(bhp x .5) / (4 x .85)

should give you to lbs/hr fuel injector size (always ROUND UP to nearest available size).

My guess is you will want to keep your 30's or maybe go to 36 but you will need a good estimate of the amount of hp you are pulling at the crank which you should be able to derive from your upcoming dyno run.
 

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Assuming you have a manual with OEM clutch, I think the consensus is 15% loss though I do not have any real data for that number, so chp = .85 x whp.

If you have auto the loss is more like 25%.

If you have getrag or something similar you may be down around 10%. these are all just off the cuff though.
 
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