I have the 350 HO crate engine, and I'm thinking about swapping the XE268 cam in. The only obstacle I see is the bottom end, which I don't want to change. It consists of cast pistons & rings, cast crank, and powdered metal rods. The max rec. speed is 5500 rpm.

My questions are, about how much power can the pistons handle and, assuming I upgrade the springs, how high could I safely rev the engine? Any opinions would be greatly appreciated.

 

what are the specs on the cam? I can tell you that the max reccomended RPMs for the ZZ4 crate is 5680 and a few times I've hit almost 6500 with it without floating the valves, still tickin away......get the specs on the cam and I'm sure you'll get some good answers

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1987 Camaro SC
ZZ4 350
Demon 750
2000 RPM converter
3.73's
Outlaw Z-28 cowl

 

The specs on the cam in there right now are:
Lift: .435 I, .460 E and Duration @ .050: 212 I, 222 E.
The specs on the cam I'm thinking about putting in, the XE268 are:
Lift: .477 I, .480 E and Duration @ .050: 224 I, 230 E; with a 110* lobe seperation angle.

 

Anyone have any good guesses?

 

My 427 puts out 500hp/520lbft and I twist it to 6000 rpms all the time and that's with a cast crank, 2 bolt mains, cast pistons and stock rods (arp rod bolts).

Miles

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88 427 Big Block Camaro
(Best 1/4) 12.18 @ 113mph 1.75 60ft
(Best 1/8) 7.76 @ 94mph 1.72 60ft

Currently installing 3.73's into my 9 bolt (YES, it is a 9 bolt & YES they are 3.73's, not 3.70. I currently have 4.10 gear sets and new series 3 posi carriers for sale for 9 bolts )
www.koolmeister.com

 

Thanks for the info. That helps a lot. Looks like if I change the springs, I'll be able to add some rpms. The engine is still pulling hard at 5500 and it would be a shame not to wind it out some more .