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Cam and valvetrain longevity....??? low duration high lift...

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Old 09-30-2016 | 09:35 PM
  #811  
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From: Traverse City MI
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Sorry Tim we are all here for you, no matter if we all like each other or not.

You have lots of time to think and plan.......for forced INDUCTION BABY!
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Old 09-30-2016 | 09:41 PM
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Originally Posted by offshorexcursion
Well when I worked with Bob he COMPLETELY FORGOT to calculate my exhaust into the build until the engines were finished, then explained that I needed new big tube headers to get the results he promised. F*** Bob and his cat!
Now how do you know Bob's not a Vee guy??
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Old 09-30-2016 | 09:47 PM
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I would be very interested to wait and see if both engine show the same wear patterns, At this point I would suggest to remain level headed, do your due diligence, and it should lead you do the smoking gun/root cause. Was this the engine that was run for a short time with the high spring pressures?
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Old 09-30-2016 | 09:49 PM
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From: Lees Summit ~ LOTO 10MM
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Originally Posted by Full Force
He's got 572's big difference lol
I hear ya there. Still may be worth some discussion To help in the quest for more power.

Don't worry, I'm taking good running motors out of my boat after next weekends fun run to chase down more power. This is a disease I swear🤑🙈🇺🇸✡
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Old 09-30-2016 | 09:51 PM
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Originally Posted by phragle
Now how do you know Bob's not a Vee guy??
I always enjoy your sense of humor!
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Old 09-30-2016 | 10:01 PM
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Heads being tore into . She gonna need a valve job for sure.

Glad I pressed Tim really hard to pull those intakes and take a look at stuff. Pretty confident, it would have got ugly had he tried to squeeze another season out of these things.

Lifters going back to Johnson for a rebuild/inspection. Randy at Johnson saw the cam issues, and suggested that. Rightfully so.

Sucks when you buy 900 dollar lifters, good pushrods, 500 dollar billet cams, AFR heads, etc , and end up with crap after 65 hours, in a engine thats supposed to be a pleasure combo, to go have fun with bar hopping and having fun. Of course, Im sure the maintenance interval sales pitch was in the ''250 plus" hour range before touching anything.

Overall, nice combination of crap.
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Old 09-30-2016 | 10:45 PM
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Originally Posted by Full Force
tim,i have been following but not getting involved.is this your block with the cam from bob and on your invoice does it state [8620 core].
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Old 09-30-2016 | 10:54 PM
  #818  
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From: Olmsted Falls,Ohio Marblehead,Oh
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Don't remember why one had the high pressures...

Originally Posted by abones
I would be very interested to wait and see if both engine show the same wear patterns, At this point I would suggest to remain level headed, do your due diligence, and it should lead you do the smoking gun/root cause. Was this the engine that was run for a short time with the high spring pressures?
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Old 09-30-2016 | 11:00 PM
  #819  
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Thanks a ton for help and advice... Gonna redo heads up... Not happy but it is what it is.. The person who helped vintage's build will be involved along with Joe and my buddy Scott... In the end I will most likely see better results... This is where I should hate started last time....

Originally Posted by MILD THUNDER
Heads being tore into . She gonna need a valve job for sure.

Glad I pressed Tim really hard to pull those intakes and take a look at stuff. Pretty confident, it would have got ugly had he tried to squeeze another season out of these things.

Lifters going back to Johnson for a rebuild/inspection. Randy at Johnson saw the cam issues, and suggested that. Rightfully so.

Sucks when you buy 900 dollar lifters, good pushrods, 500 dollar billet cams, AFR heads, etc , and end up with crap after 65 hours, in a engine thats supposed to be a pleasure combo, to go have fun with bar hopping and having fun. Of course, Im sure the maintenance interval sales pitch was in the ''250 plus" hour range before touching anything.

Overall, nice combination of crap.
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Old 09-30-2016 | 11:02 PM
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Looks like the lobes have some tracking issues on the opening side. I think that would mean, either the lifter acceleration rate if too steep , too much spring pressure, or simply, the heat treating of the lobe is no good. Even with solid roller spring specs, to do that to a billet cam, whether 8620, 8660, etc , shouldnt be happening. We arent talking 1000 lbs of open pressures like some engines run.

Im sure theres a reason companies like comp, crane, lunati, howards, arent doing .400 lobe on a 241 degree cam. But from the other cams ive seen come from haxby, mer, another diy guy, and now tims, it looks to me, like theres a serious heat treating process on these custom ground lobes.

But im no cam grinder. It be interesting to send the cam out and checked for hardness. Im gonna forward these photos to Mike Jones, and see what his take is on them. He actually grinds cams, heat treats them, etc in house.
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