Guys I'm building a pretty comprehensive buildup.

My block is a standard B18C5 short block with oversized CTR pistons.

Where can I find information to calculate the compression ratio? I know about http://www.c-speedracing.com, but I found it to be a little inaccurate.

I want to be running close to a 12.5:1 or higher compression ratio. I don't want to mill my head. So the other option is to run a thinner head gasket. Toda makes some thinner headgasket. Their thinnest one is rated at 0.6mm. Are there any recommendations for a thinner head gasket? How does the stock 1 layer headgasket hold up to the abuse? My engine will be equipped with ARP Head Studs by the way.

Sorry to keep jumping around with the questions, but about the CTR pistons. Is it safe to leave those sharp edges on the tip? It looks like some casting imperfections right in the center. Could I use a dremel tool and lightly take some material out?

Thanks in advance,

The n00b.

 

0.6mm is stock OEM basically. As for the pistons, I would have a machine shop sand/machine down the lumps in the middle and balance them.

 

I too had these "imperfections" U just had the machine shop remove them and then re-balance the pistons. You'll be close to 12.5:1 compression with these pistons in your block.

 

i jus reacently bought ctr like 2 days ago and
hmo told me that my c/r would be 12:1
i have a 95 coupe with B-18c already high comppersion

 

Well you said B18C5 short block. What head? If you are running a PR3 head then 11.8:1 w/ O/S PCT's w/ stock valves, unmilled head, stock gasket etc....

 

get your head milled a little too, then you should be 12:1