headgasket blew and now a bad piston

[Mugsy]

well my buddy just got a new setup on his car, 20g with exxternal gate and bigger injectors, now we took it to a shop close by we here is really good. while hes tunning it the gasket blows, so we take it home and tear it down, replace the gasket and we start it up, theres alot of blowby, thought it could be because it had huge injectors and wasn't set at idle right or hoping something simple, we take it back to the shop, then while tunning it losses a cylinder aka sounds like a wrx, then we get it home.....again, tear it down, take the pistons/rods out and the number 2 cyl had some detonation, side of the piston chipped off with a hole through the piston farther down. now the machine shop guy said it could be when the head gasket blew it hydrolocked, but that doens't make sense unless it chipped some before then getting on it again it finished off? and the shop owner says we should check the injectors cause it could be its not flowing right. What do you guys think?

 

[Whitetalonb16g]

that sounds just like what mine did, headgasket blew we fixed it then find blowby, low vacumme and then a bad misfire. We pulled it apart, found a bad balancer belt, did the eliminator kit and the car still misfired. Did a compression test and found 0 in the #4 cyl. Pulled the head, 1 piston was melted and it killed the block.

Still to this day I don't know what caused it.

 

[Mugsy]

thats reashuring, well hes prolly gonna get new pistons and the block bored, on this one, its more of like a chip on the side and it looks scored on the side a little then a hole about where the rings are

 

[Whitetalonb16g]

ask him if he could get a pic, I would like to see if its almsot the same damage. look at my profile gallery and see mine

 

[Mugsy]

ill get one asap, but i dont see the pic of a piston in your prof, only car pics

 

[Whitetalonb16g]

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[Mugsy]

looks exactly the same to me, same area at the top side as on this one

 

[trbotaln]

that piston definately looks like it was a victom of detonation. detonation is usually cause by a motor with the incorrect air/fuel ratio or back vacuum.