Cam and valvetrain longevity....??? low duration high lift...
#813
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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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#816
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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.
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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#817
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#818
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Don't remember why one had the high pressures...
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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#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....
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.
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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#820
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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.
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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