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Just got the motor out, had a crane 741 cam in it, those are supposed to pull pretty good rpm in a 509 with a blower?? Guess maybe it had valvetrain stability issues??

Quote:

Originally Posted by Daytona25 (Post 4671717)

Just got the motor out, had a crane 741 cam in it, those are supposed to pull pretty good rpm in a 509 with a blower?? Guess maybe it had valvetrain stability issues??

I don't know any of the crane numbers. See if the valve locks are stuck bad and take a look at the valve shims that can tell you a lot if it was not stable.

Quote:

Originally Posted by Daytona25 (Post 4671717)

Just got the motor out, had a crane 741 cam in it, those are supposed to pull pretty good rpm in a 509 with a blower?? Guess maybe it had valvetrain stability issues??

If nothing else, that’s the easiest cam to sell if it’s in good condition.

The 741 has a little more overlap than a norm blower cam,ital work and make the power,mine has a little tracking from low port velocity, but prob the reason i can run more boost on 93, the cam company's should have a good marine blower cam. also would call Kip at Cam Motion, he was making some big power on the old (HotRod mag)Pump gas drags, I would think that would carry over to marine blown on 93 etc. I wouldn't run a solid roller, just harder to adjust the lash with headers,Ive ben running solids on street cras/race cars awhile, really dont see much change in valve adjustment,but i do spend the extra running the Crower stuff,helps a buddy thats WD with Crower to.
You should beable make 800's easy with the heads your talking about,My Scarab motor /494.8/71,2 1050's,innercooler made 828 at 7200 w/ hyd roller, Crower lifters,All Crower guts.
My Hustler is 500efi,741 cam,I ported the stock steel heads myself,whipple 3/3 etc, it made 840s at 6-6100, 8.5 boost, Last rebuild went with new Dart block,no other change except dyno w/ 93 ethanol fuel made 883 at 6000.thats crane 741,crane gen 6 style 500efi hyd lifters,gold rockers, 1 step above 929 spring,

If ya get to radical on cam etc the idle gets worse, docking,

I didnt read the hole thread, not sure your carb or fuel inj, just my 2 cents.

good luck with your combo,
Rob

I ended up goin with the afr 315cc fully cnc ported heads, a Lunati 245-250 duration at .50 blower cam, hyd roller comp short travel lifters, crower stainless shaft mount rockers, 8.2 static compression gonna try to run 8lbs boost below intercooler, also it’s carbureted I have 2 980cfm Nickerson carbs. Hoping to make 850hp??

Probably could of gave it little more cam but think you will get your 850.

I was afraid to over cam it and have a motor that didn’t idle well, seems people have seen 62-6400 rpm with the 651 crane cam and this one is about the same size just a touch less lift, so I thought it would be plenty of cam??

The 651 is on a 114 lsa the Lunati I picked is on a 112lsa

im curious to see what you make
i just did a 502(575sci rebuild), 7.5:1 compression, AFR 315 heads, 741(525) cam, 8-71 and small ass TBI. made 775hp at 4psi. so im sure you can reach your 850 with ease