I bought a set of CP pistons flat tops for a 406 build-up. They were purchased on auction from a closed out speed shop. The auctioneer didn't know they were for SB2 heads and I failed to check them out myself. My question is can I still use these pistons if I use 23 degree heads? My reasoning is a true flat top would work with the small cam I am using, so valve clearance is not a issue. I'm questioning whether the different valve cut-outs would cause quench or terrible combustion turbulence if used with a 23 degree head?

 

being flat tops i'd say use them, but what i'd really do is contact the piston maker and ask them instead of listening to what i have to say on the net.

 

I did just that with no reply yet. I figure a lot of responses would be better than just mine.

 

My mistake! Actually the piston is a dished piston. Attached is a photo and information. Now how convoluted will the combustion process be ??? And here's a thought, G1 or G2 Trickflow twisted wedge heads have the intake valves at different angles and they don't require a special piston. Trickflow sells a special piston but they don't require one. Maybe I'm just talking myself into using these

 

That is one WEIRD looking piston, my friend. Doesn't look much like a SBC piston at all. Not only are piston/valve clearances something I'd check, I'd also check for piston deck height with whatever rods/crank you're using as well as CC the dish to figure out how much you've got there and then calculate your compression.

I'd hate for you to find out that the piston is sitting way down in the bore or popping up above the block's deck with your particular combination of stroke and rod length. Pistons for an SB2 heads on a 400 block........ I just dunno about that. Sounds odd to me.

There are alarm bells going off in the back of my brain when I look at that piston. Something is NOT RIGHT here, but I'm not putting my finger on exactly what in this post, I'm sure. You better measure the snot out of every possible measurement before you put them into your 400.

In short- DANGER, WILL ROBINSON! DANGER!

Seriously, something is whacked here. I can feel it in my DNA. This is WRONG somehow.

 

Good suggestion, Damon. CP has verified that the pistons are SB2 by the label on the side and by the pictures I have sent them. They are a custom run they do for a NASCAR team. They offered to check out the pistons for free to be sure all dimensions are consistent with that on the label. All I have to do is ship. Make's me feel good about how some companies handle potential customers when there is nothing in it for them right off. If they are as labeled, they will work with a 3.75" stroke and a 6" rod in a 4.135" bore. That's a 400 block that is bore and honed to .010 over. That was an important consideration for me in that I have a very low mileage 400 block that will clean up .010.