Matt if you ever do put together a full kit let me know. I like the set up but I don't want to have to the R&D.

Are the ports / valve stems shrouded. It's hard for me to tell but the combustion chambers look very deep and those where the FU / smog head.

I understand that he is all red and hangs out with horned beasts but he brought me a sheet metal bending brake so he's OK by me.

We're cooking up a bunch of Italin food for Christmas Eve so the holiday is off to a good start

Hopefully everyone else is enjoying themselves.

Happy Chanukah, Merry Christmas, Buon Natale, Feliz Navidad & Mele Kalikimaka to you all.

That sounds about right, I erred on the larger end of spec just to be safe.

I wish I could offer definitive advice; I'm with some of the other guys on detonation, my experience with it has always been melted pistons and busted ring lands.

Note I also use a ring spreader tool to install them.

SW Motorsport had them at a decent price I was planning on ordering them but they became available from Rockauto.

a12dato120y I'm running 38 degrees of total timing but I use 100 octane fuel.

Dave they are 6.5mm deep.

I'm going to give up some power over buying another set of flat tops from JE (probably 5-6) but as these were on $99 I'm willing to live with it. I have to check but I also may be able to go back to running 91 octane pump gas. I'm expecting the motor to be around 95hp at the wheels.

I just got a set of A15 pistons, ITM # RY6119 and can confirm that the dish volume is 10cc. Note this is the offset dish style.

Since this question comes up from time to time I'm posting this so people can find it in a search.

Also note the compression ratio with a GX head (29cc chamber) & GX .8mm thick gasket will be 9.89-1.

I've run 12-1 compression & 8200 rpm in the A15 and 11.8 compression & 8600 rpm in the A12. I've never had a ring break.

Something isn't right; either the ring end gaps or as rgrinder mentioned it snagged when the piston was installed.

I'm also not using any fancy rings just standard Hastings or other known brands.