zt260

I'm building a 540 tall deck with a whipple quad rotor 2.2L EFI. What do you think of the AFR 357cc CNC heads? Any suggestions for the cam and injector size would also be welcome.

Beak Boater

We used the 325 AFR CNC heads on a pair of 540s with a single Whipple. Crane 741 Hyd roller, and 50 lbs. injectors. JE reversed dome pistons. 7 pounds of boost. Idles at 750 rpm and the motors pull hard all the way up to 5600 rpm. Heads are first class. Dont know if they got caught up. It was about 4-6 week wait for a set. Good luck with your quad setup.

zt260

We have a set of AFR 357's on the bench ready to go if they are the real deal. I was thinking of a crane 741 with 83Ibs injectors. I plan to run 110 octane and 13Ibs of boost. The goal is 1200HP, or 1000HP on 93 octane.

paradigm shift

Well I think the 741 is a good cam but not sure it is enough for what you are trying to build. I know nothing though.

Turbojack

I think you will be on the short side with 83 lbs injectors if you are going for 1000-1200 HP.

cstraub69@comcast

What is the bore, stroke, rod length on this 540 combo, I will figure the air needed to do so.. .but I think your going to fall short if this is to be a reliable power plant.

chris

jspeeddemon

Everthing I've seen on the AFR's has been super positive, will be my next head purchase. 83 lb injectors will cut it by turning up the fule pressure, every 10 psi gives another @7lb rating, so just start with extra 10 psi over where they are rated, probably 43 psi, for that kind of HP.

zt260

bore 4.50 stoke 4.25 I don't recall the rod length, I will check. It will be 8.25:1 compression.

I'm not sure how reliable any 1000+Hp motor really is...

cstraub69@comcast

Assuming it is a 6.385" rod, and target rpm is 5400 max, you need a maximum head flow of 349.87 CFM.

Chris

zt260

These heads are solid lifters with stud girdles. The max will be 6500rpm.