SStressin

iTrader: (5)

so im getting ready to bite the bullet and purchase my headunit. im looking for a max boost at around 18lbs on my 403 with an f1a this is on an fbody with the procharger fmic, big red bov and aster bracket. going to use the procharger 7.65 crank pulley.

my setup is looking like this

ls2 aluminum block. depending on staying 4.000 or go to 4.005
weisco/diamond pistons, compstar rods, dragonslayer crank
frankenstein porter castings trickflow cnc heads. should be in the 227cc range
shooting for 10. to 1 compression.
custom speced cam by martin or geoff at eps
brian tooley .650 dual spring kit with titanium retainers
ported fast 102 by chris frank and 102 nw tb
kooks 2 inch x 3 headers into there newly designed 3 inch y into a cut out and magnaflow catback

Detoxx03

iTrader: (14)

How much power are you shooting for?

SStressin

iTrader: (5)

Im hoping for 900rwhp to 950 at 18lbs for big events. Id be content to pulley it down to 12-14lbs for cruising around town going to car shows. Maybe if i can get it to 700 rwhp on 12-14lbs

Detoxx03

iTrader: (14)

Don't worry about the psi number too much. It's only a measurement of restriction. If the setup is efficient it can make 900 on 15-16psi or 18-22psi. Just depends on intake, heads, cam, exhaust flow, etc.

Just throw a 4.2 or 4.0 on it and see if you hit your goal. If not throw a bigger or smaller pulley on it depending on which way you need to go.

SStressin

iTrader: (5)

i will probably make my goal on around 16 pounds im figureing. with frankenstein trickflows, a ported fast 102 and some 2 inch headers. im building this setup with the best of the best so it should be pretty efficent. i was curious as to how high i can crank up the boost without overspinning a f1a when i turn it up or should i get a bigger blower.

Blown06

iTrader: (32)

Beside a few small details I'm running a similar motor in my truck, but with an F2. So I say sell your F1a now and buy an F2. lol

Bob@BruteSpeed

iTrader: (16)

F-1A has a 74,000 rpm rating

To determine the impeller speed, the following formula is used:

Maximum impeller speed = crankshaft pulley diameter (N1) divided by supercharger pulley diameter (N2),multiplied by the step-up ratio (4.10 for the P-series/D series - 5.40 for the F series), multiplied by engine rpm at redline.

7.65 divided by 3.90 x 5.40 x 6800 rpm = 72027 rpm

A 3.90 pulley is what I would go with. Bob

Detoxx03

iTrader: (14)

Yea just make sure what max rpm you plan on revving to and go from there but Bob has the right idea.