bought a rebuilt b16 block from a friend all assembled and ready to go
he's not entirely sure of the exact cr either...he also bought it like this and lost the spec sheet.
just wanted to see what some experienced engine builders (obviously, i am not one) think the cr is around.
its going to get a stock b16 head (and internals) for now but i also have some s2s2 cams and valvetrain on standby if it is deemed safe to run such.
any ideas?
block has b16 supertech pistons (was told will yield 12.5:1 with b16 head), eagle rods, arp, etc..
some told me from pics that these look higher than claimed.
on supertech's website the highest ots pistons for a b16 is 11:1
so i take that these are custom ordered then?
any help/input is appreciated
i dont expect a definitive answer. just maybe confirmation that these aren't super crazy pistons like 13 or 14:1 lol

 

They look 12:1 - 12:5 to me...

 

cool. thats 1.
thank you for your response
anyone else agree or disagree?

 

Without a part number for those pistons its impossible to tell by looking. CTR pistons look similar to that installed and they would be 11:1. Other than that you'd have to CC chambers with the head on.

 

They could be custom.
http://www.supertechperformance.com/custom_pistons.html

Dome look similar to Wiseco K593.

 

Battle -even w/ a good tune u may still have to worry about using pump gas.

 

Actually, your totally right. That was just a complete guess what i give.

 

bingo! one of my buddies actually said they do look like PCTs too.
its my first semi-built engine (im more of a stock-with-bolt-ons kinda guy) so im a little apprehensive lol
thanks for your input fellas

 

Those are not ctr's.

 

11.4789-1 visually.

 

looks kinda high bro. just clay it to be sure.

and use the s2s2 cams, or if you can find a pro1/rm m21 better try to use those instead, you will be happy to use cams with big primaries on the circuit with a b16a

 

on a b16 they dont go past 11....remeneber ctr pistons yield 10.8 compression on a b16b...and 13+ on a gsr

 

CTR pistons do not yield 13+ on a GSR. Ask me how I know. Plese don't just spout stuff you don't know.

 

hey joel!
thanks man. i'll look into all that.
just looking for consensus these aren't crazy high slugs lol

 

They have a pretty high dome, as suggested, definitely check your clearances with clay. They aren't crazy looking tho, only thing you can really do is CC it and see what you're working with. Also, remove them and check on the underside for a Part Number.

 

lol 13+?
more like 11.5 in a p72 dude

 

much appreciated

 

The shorter deck height of the B16a gives it a higher compression ratio that is around 11.5:1, using those pistons.

On a GSR with a P72 head, you'd be in the high 12's (12.5-12.9:1) range and wouldn't go into the 13+ unless you were using the LS block/crank/rods.

No one said they were. It was acknowledged that CTR pistons have a similar dome and would look similar when installed. That's why guessing what the compression ratio would be by visually looking at the crowns isn't very accurate.

 

high 12s on a gsr to low 13:1 isnt a big difference....but its defitnetly not 11:1.....but those pistons are less than 11.5 :1 on a b16 unless its a stroked block...so you should be safe...you need some custom pistons for 13+ on a b16...

 

Clay it already.... This guessing **** is getting old..

*Edit*. I do realize that I sound as though someone pissed in my corn flakes this morning.. but my message is clear