Take a look at this block cylinder 1 good or bad?

[phyregod]

Tighten it to 134 ft lbs and stake it with an old flat head screw driver and a hammer on the outer edge, into the little square indent. Should look like this:

 

[phunky.buddha]

thats looks like valve cleareance issue to me. Plug is in the middle of the head. The dings are on both outer sides of the piston.

i would say his valves were improperly installed on that chamber.

You can separate the plug tip from the plug body with a good bit of detonation- a bad tune or just one bad bang could have done that.

 

[Taco15]

yeah but look at the rest of the cylinders. not to big of a difference but there is a difference unless they cleaned the other cylinders.

i see what your saying though. Plenty of things could have happened

 

[5speed]

well i asked the owner, and he said he has no idea what it is either, he had it built and put together, then he took it to tune at 15 psi. Afterwards he ran it at the tracks, he then pulled it out and part out his motor, he then noticed that the cylinders and pistons looked like that. So he has no idea what could've done it. I dont think he had a clearance problem but the pistons do look pretty bad.

 

[phunky.buddha]

yeah but look at the rest of the cylinders. not to big of a difference but there is a difference unless they cleaned the other cylinders.

i see what your saying though. Plenty of things could have happened

I don't see anything wrong with the other cylinders- just machining marks on the tops of the pistons and carbon buildup.

 

[vtecsir1]

looks like detonation maybe, spark plug tip too but here is a pick from a head i pulled off a friends itr motor that had 2 tips break off in. the pistons didnt look like the one you showed but the tips turned into little bb's and bounced around so maybe that is what your piston had happen to it. Just odd it didnt hit anywhere else but those sides.

Did you actually see his head that he pulled off?

also is just me or did anyone notice the outer cylinder looks like its cracked at the top in the pic with the bad piston?

 

[illinSI]

i would slap the head on it and go. doesn't look all that serious. some debris got in the cylinder. doesnt look like it came from the piston or block so it should be fine. see if he still has the head and snap a pic of that cylinder