Re: Ken's 1937 120 Touring Sedan

Posted by Ken_P On 2020/8/18 7:15:41

To knurl or not to knurl...

So, I have a set of piston expanders, and they look good. I also found a guy who can knurl the pistons... but ... he doesn't want the block in his shop (because it has a car attached!!! ) and I'm concerned about having him knurl the pistons without the block to compare it to. Thoughts?

I also ordered the piston rings, then noticed in the shop manual where it specifies a different type of piston ring (specifically the top ring) when piston expanders are used. It is an expansion type ring with a groove on the inner diameter of the top of the top ring, to aid in sealing. So, if I can find a set of those rings, I'll probably run the expanders. If I can't, I might risk knurling, knowing some hand work would be required if he takes a piston too far.

Anyone with more experience have any suggestions or good ideas? Not planning on making any decisions until I get back from my valve grinding excursion this weekend.