Okay.... I have built a few engines in my life, and I have a close friend that is 30 year man in the engine building business. I, nor him have ever heard of anyone doing that. I am not saying you can't do it..... but pistons aren't necessarily just a round plug...... and in fact most aren't. Not to mention cutting in the ring lands and what not to accomodate the loss of outer diameter.

I fail to see how that would be cheaper than .020" pistons if you were stuck on that bore size.

Anyone else?

 

Yeah, that's just bat-**** crazy IMO.

 

Wow, that's different.

 

Everyone buys .030 pistons. He could have sold those without losing much $$, and bought the .020 over ones. It would be tough to machine those, they aren't the same size down the skirt. (From what I have heard, I have not measured them)

 

If anyone ever questions why I bag on the local "experts" for my part of the world...... Well read the opening post, lol. Local large engine "performance" and dyno shop that builds engines as well as doing custom tunig. Yeah..... and you wonder why I do everything myself. That was only the first problem on the list with that guys particular build.

 

Bingo. And you mean to tell me some hillbilly local shop is going to exactly match all the original dimensions and tolerances of that piston after shaving everything an even .010"...... I'm sure. Even if they did, they would charge more than the new pistons are worth to do it for setup alone.

 

what alot of people fail to realize is .030 over is only .015 off the cylinder wall

you dont machine the block per piston size you machine the block to clean up the bore make them round again. I never order pistons til i know what size the block will take

 

Radius must really confuse some people you know then and honestly that's not the issue here anyway. It is fairly easy to determine once you measure the block and find how out of round it actually is what you will likely need to straighten. It's math, not rocket science. Now if it specs out good to start with you might only need 0.020", or even 0.010"...... Still a lot of people just go with the seeming standard 0.030" overbore regardless because of simplicity of parts, even if it cleaned up at 0.010". But that's not even remotely the point of the discussion.

His cylinders were straight at 0.020".... they wanted 0.020"..... Engine kit came with 0.030" pistons which the shop decided to make into 0.020" pistons. That is where I went

 

.. ITS LIKE WTF?? They wanted .020 but did not take the time to make sure the kit was .020??? Thats where the problem is if you ask me besides the oh you can turn down those pistons and make em work

Now on the othe rhand .. if I ordered .020 and it came .030 then someone is shipping my **** right overnight!!!

 

Usually I order pistons last, after the block has been prepped. That way we know the bore size and deck height on the block.

I have never heard of anyone machining pistons to turn them down.
But what do I know.