When I purchsed my a12 in Feb., the motor was rebuilt and blueprinted but never installed in the car or fired (since 1986!). By luck, when I wrote the OK DMV, a copy of the receipt was in with the rest of the paperwork. But there are no specs. Just shows new pistons, cam, bearings, balance and head work.

Anyways, I'm going to install a Bob K. cam that I have and a set of new springs, seals, and lifters. When I pulled the heads and checked the depth of the .030 pistons, they seem to be averaging around .102 deep.

I've done an ameature check of the CC's on the heads and though they have been milled (not sure how much), I get roughly 85cc's. They are the original 906's.

So now the questions:

1) Should I use the stock MP Hemi springs or C-Cams 993?
2) I do have a new set of SS valves that will lesson the CC's since they are not concaved. Should I go ahead and do this and install hardened seats?
3)Should I use a steel head gasket, felpro blue, or ???.
4) I'd like somewhere around 9.5 compression.

5) This car won't see much racing, but I'd like to get in the high 12's. It will be completely stock, except Bobs cam. Which is near stock and legal.
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you have your deck height and head cc's . plug that into kieth blacks cr calculator & see where you're at. http://kb-silvolite.com/calc.php?

It appears that you will be somewhere in the low -mid 8 range.I would install the valves and hard seats.The MP springs will work fine.Thin gaskets if you can find some.I would like to see the comp ratio at at least 9-1 or close to that.Possibly some head and or block milling (expensive but only way to raise the comp ratio).With a very good set up on the car 12's can be run.Good cyl heads will help alot.No less than good int port match,exh port clean up and bowl job.

Put the thin steel head gaskets. they're good for 1/2 point in compression.

Using the numbers you provided with a steel gasket C/R is 8.95 with a comp gasket 8.65
If you really have 85cc 906's the've been cut about .020 you could cut another .020 off & get them to around 80cc which would get you a 9.3 C/R

BTW if you do this the intake surface of the head needs to be cut .058

the bob k. cams are engles. i'd use an engle 833 spring. the 833 will allow for more lift, which most of the engles have, without a pressure compromise. as stated, be sure and check retainer to guide clearance.