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Quote:

Originally Posted by jsand117 (Post 4487849)

Is there anyone out there that bought a set of MK cams and ended up with stout running motors that made good power??

As I mentioned in my earlier post, I bought my MK cam from another OSO member, BBCLiberator. He was running an identical cam in a 509 with stock GM rectangle port heads, Eddy Air Gap manifold, Holley 800 (or 850?) carb, Stainless Marine manifolds, IIRC. Maybe he will see this thread and chime in on how his build is holding up. Back when I bought the cam from him he was very happy with his build.

I am wondering if the MK cams that have milder lifts are going to have the same issues with valvetrain harmonics and keeping the wheel on the lobe as we are apparently seeing with some of the more aggressive designs. Mine was relatively mild lift, only about .596 and .612. Now of course that had accordingly shorter durations on the lobes - 226* and 230* on a 114 LSA. Like I said, I have been hearing an odd chirping sound that appears to be coming from the exhaust, but I have not had the time to get out there to really diagnose the damned thing. Plan is to pull the heads and take them to a machine shop to take a look at guide clearances, since I never did that when I put it together. Tim's problems have me spooked enough to do this, along with the odd sound it has developed. Hoping to head any disasters off before they happen.

In all honestly, I am frustrated beyond belief to be spinning wrenches on a boat I hardly have the time to take out anymore. Truly tempted to drop a motor out of someone's Suburban in it. :party-smiley-004:

Quote:

Originally Posted by jsand117 (Post 4487849)

Is there anyone out there that bought a set of MK cams and ended up with stout running motors that made good power??

yes.............I answered the question, don't make me out to being a cheerleader :cheer:

Budman, what rocker arms are you using? just curious.

Has anyone had any contact with Bob lately? I shot him an email the other day about my springs and haven't heard anything back.

Quote:

Originally Posted by abones (Post 4487954)

Budman, what rocker arms are you using? just curious.

Scorpion marine endurance.

Quote:

Originally Posted by Mr Gadgets (Post 4487785)

Interesting read! I have one of bobo's cams with 20hrs on it and 5 bad lobes, or was it 4.. The only reason I only have one cam of his, is because I sent the next one, that I did not order, back to him. He has hated me ever since for making him eat $350. That was in 2008. The block I ruined with that cam sits in the corner waiting for a rebuild. Too much metal in the skirts and scars on the walls to just reassemble. My loss was a motor worth 100 times more than his loss!
Some day I would like to put a big crank in it and slide it under a old Chevy cab over.. Maybe..
Hopefully others will not drink the bobo Kool aid and learn from other people's stories.

Dick

Was that a Cam Motion 8620 core?

Quote:

Originally Posted by 33outlawsst (Post 4487953)

yes.............I answered the question, don't make me out to being a cheerleader :cheer:

You have 540s too dont you? I forget . How many hours ? Any issues since built?

yes 540's around 50 hours with no issues, they have gone to a new owner so I wont have any more info to share.

mk cam,scorpion rockers.low power 454 with afr 265's. and stainless marine exhaust.not sure of hours yet will find out.thinking of looking into it just to see.no problems so far.Im one of the 385 to 500hp builds tim was talking about earlier