What's wrong with AFR's exhaust port?
05-25-2015 | 04:54 PM
#201
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From: Olmsted Falls,Ohio Marblehead,Oh
Whos to say the guide clearance wasnt simply too tight , from a quality control standpoint ? Without physically checking it, you're taking someone's word for it.
While it certainly may or may not be the root cause of the failure, I certainly wouldn't write "improper guide clearance " off as a possibility, because someone else ran Afr heads with no issues. They need to be checked imo plain and simple, as well as the valve jobs.
Exact reason why Id rather buy my heads bare, and have my machine shop assemble them.
While it certainly may or may not be the root cause of the failure, I certainly wouldn't write "improper guide clearance " off as a possibility, because someone else ran Afr heads with no issues. They need to be checked imo plain and simple, as well as the valve jobs.
Exact reason why Id rather buy my heads bare, and have my machine shop assemble them.
05-25-2015 | 04:57 PM
#203
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From: bel air, md
Anybody can look at the top of that piston and see detonation. You have carbon in the center and shiny all around the outside of the piston I highly doubt this was such a detailed build that you manage to push all the fuel to the center of the piston and ignite it. It's detonation see it all the time there are many reasons it happens timing is one of them...
05-25-2015 | 05:03 PM
#205
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From: Traverse City MI
Tim so sorry to hear about your issues.
NONE of us deserve this to happen
Let's hope OSO can constructively help give ideas and pointers instead of 100% confidently diagnose an engine issue through a picture! Lol
NONE of us deserve this to happen
Let's hope OSO can constructively help give ideas and pointers instead of 100% confidently diagnose an engine issue through a picture! Lol
05-25-2015 | 05:04 PM
#206
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From: Olmsted Falls,Ohio Marblehead,Oh
[ATTACH=CONFIG]541411[/ATTACH]not bad timing at all....
Anybody can look at the top of that piston and see detonation. You have carbon in the center and shiny all around the outside of the piston I highly doubt this was such a detailed build that you manage to push all the fuel to the center of the piston and ignite it. It's detonation see it all the time there are many reasons it happens timing is one of them...
05-25-2015 | 05:14 PM
#209
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From: Moultonborough NH
Just an idea Tim, but I know you had some intake sealing issues with these motors initially. What are the possibilities that you had an intake leak from the valley on that cylinder? You might not see it on the wideband if it is only one cylinder running lean. Are you running widebands on both banks or only one per motor? I really can't imagine a tight guide seizing the valve that quickly, and if it was tight guides I would imagine you would see the failure on an exhaust valve first.
