DopeFedZ

iTrader: (34)

I finished my build on my FRC recently and was wondering if my numbers seem about right or if I should pulley down the blower to get the max impeller speed up closer to what the blower can support.

List of mods
iron block 5.7 forged internals 10.5:1 compression
AFR 205 / ls6 intake and stock tb
arun jam cam
kooks 2" headers / 3" xpipe which drops down to 2.5" at axleback
fic1300 injectors/ dual walbro 450 pumps / E85
8" innovators west balancer
4.25" blower pulley
procharger f1a

Car made right at 800hp on 19lbs. I was thinking I could get closer to 850-900. Just wondering if I should swap pulley to either a 4" or I think the other size was a 3.90.

SELLSZ06

iTrader: (12)

Those are really good numbers! You have to try both sizes so buy both, run them to see how much it makes then sell the one that doesn't work, they sell pretty quick.

Detoxx03

iTrader: (14)

I would pulley down. That blower can make 900 easily.

BCNUL8R

iTrader: (2)

DopeFedZ

iTrader: (34)

Only pic I took.

NitrOmm

iTrader: (1)

Nice numbers. Wish we could see the TQ curve.

8" crank pulley with 3.9 SC pulley @ 6,500 engine RPM = 72,005 RPM impeller speed.
74,000 is the recommended max.... so you are good to go on that side.
Belt slip may become an issue ?? but the F1A can support the RPM if that is your concern.

Love that Jam Cam !

DopeFedZ

iTrader: (34)

Yeah thats what I was thinking about doing. I called dallas performance for the pulleys. They told me with the smallest id be at like 25lbs just wondering if thats too much and im getting greedy.
Yeah i probably will.
Ill see if i can get a better pic of the graph.
Gonna see if i can get a better graph pic. Thats kinda what i came up with with the impeller speed. Just wondering if 24-25 psi of boost is asking for trouble. I think ill be ok with belt slip i have a 10 rib setup and a&a secondary drive

DopeFedZ

iTrader: (34)

Last pull

Detoxx03

iTrader: (14)

It’s built and on e85 I wouldn’t worry about anything. Hell mine isn’t built and I pump 18psi through it and plan to pulley down again. If the tune and octane is on point let it eat.

BCNUL8R

iTrader: (2)

Looks like an excellent setup as it is for the street.