Need Help With Cylinder ID

[Mifintifin]

I hate playing detective, maybe someone can help. I'm trying to figure out what P&C's are in my 82 SC 3.0L without tearing it down. The top side of the cylinder base show the usual tolerance and height stamps, but no manufacturer stamp. The bottom side of the cylinder base have an M10 stamp. (rough drawing below). They have a slight magnetic draw so they must be Nikasil. I know that this engine was rebuilt by the PO at 85K miles. I don't think these are the original P&C's. Can anyone ID them for me?

Thanks

Mifintifin

82 SC Coupe
83 SC Cab

[Bill Verburg]

The #s left to right(1 is missing!!) are;

• Manufacturers ID(MIA)
• Tolerance group for cyl. diam. (3 for Mahle or KS = 95.021 - 95.028, the pistons will have different tolerences depending on manufacturer)
• the 5 in the triangle is the cylinder height tolerance in this case 85.400-85.425

[Mifintifin]

Thanks Bill,

Your first comment is correct, the manufacturer's code is missing! The 3 and the 5 are the tolernace and height codes.
Given that my 82 will run rings around my 83, I suspect that these may be either 98mm or 100mm, not the original 95's.

I was hoping that someone would have seen the same markings and would know what size they are. I have been trying to come up with a way to measure the pistons "in situ" but haven't had any brilliant ideas. I have measured the stroke and it is 3.0L.

Thanks,

Mifintifin

82 SC Coupe
83 SC Cab