Originally Posted by MILD THUNDER (Post 4308441)

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.

Originally Posted by Full Force (Post 4308442)

How was I detonating with 12.2:1 and 32 degrees timing, i don't see detonation here

Originally Posted by Full Force (Post 4308444)

Crap blew into intake and went I to each cylinder there is stuff all over

Originally Posted by Black Baja (Post 4308446)

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...

Originally Posted by Full Force (Post 4308450)

[ATTACH=CONFIG]541411[/ATTACH]not bad timing at all....