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Thanks Kev…I think my intakes are sealing..and do think my rings are pretty worn …I was hoping that the low compression may have been related more towards the valves and wouldn’t have to do rings but I’m going to do some new tests tomorrow regarding the valves sealing…been getting some good direction here to even get where I’m at now..appreciate it…

Well spent day trying to figure out these exhaust valves and why they won’t fully seal…I think what’s happening is that there is so little metal left on seat or the valve face that when I try to lap them it makes a grey ring but that ring is being created by the minimal contact points left between them… when I mark up the valve face with tick marks and spin it…I never get all of the marks broken..the more I lap and repeat..less marks are broken…this is after I had cut the seats and removed all the pits and burrs..seats are nice and correct angles…so the only thing I can think is I need new valves that hopefully may be thicker as they are new..I had my valves re ground by a machine shop but have no idea how many times in 84 years they have been ground? Does this sound like a possibility? Tks

Am very confused and need a picture. The exhaust valves are OK if they still have 1/16" of an edge at the top surface. I'm wondering if somehow your valve seats in the block are not concentric with the valve guide.

I think my valves have ground too many times and they are too small in diameter to make contact with seat diameter.. I had a new exhaust valve from Kanter so I swapped it out with one of my exhaust valves.. lapped it and seals nice.. took me 2 minutes to get a solid seal.. all the others do not seal no matter how fresh the seat cut is or how many times I lap them.. they seem to just fall into seat and bottom out at margin as if they are just hanging by the lip of valve head without any interior contact

Without seeing a picture, it sounds like maybe the old valves were refaced too many times, or maybe at the wrong angle? Could also be the stem is slightly bent, but they would've picked up on that at the machine shop. Either way, if new valves solve the problem then that's an easy solution.

Thanks…getting them in Monday..hopefully solves issue..I’ll report back…

So I finally figured out that because I re cut my valve seats with the neway carbide kit..they will not seal until engine fires up..whether I lap them or not…I learned with neway the lapping is only to check margin seal line and width…I had only 30 psi in all six cylinders after cutting and lapping them but they all looked real nice and tight..anyway..threw head back on and after running it for 20 minutes..let it cool for half hour and now I’m getting 95 to 100 psi out of all cylinders..prior to valve work I had 60 in five of them and 35 in one of them so I am pretty happy with that! Thanks for all the help and patience with me here..I appreciate it..now back to the body work!

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Glad it worked out! I didn't check compression before we started the engine in the '52 we rebuilt. After starting and running it through a heat cycle, I tested when it was cold and we had good numbers. Don't forget to retorque the head after letting it cool back down. Recheck it after driving for a while too.

Tks.. yes I did torque them down again… wonder what compression was when car was new? I know it’s a 245 six with ratio of 6.39 but don’t know how that converts to psi numbers?

6.39 × 14.7 psi = 93.93

Compression ratio times 1 atmosphere (14.7 psi) equals ideal cylinder pressue