Help on 408 build
Kudos for your quick help, 67ac! OK, yes, those HAVE been milled a bunch... .040 or .050" from stock. The OP's original number of 11:1 SCR is close; I get 11.4 with the head gasket, chambers, pistons, and true .000" deck height). And DCR is around 9.4 so that explains it. DCR of 8 or under is a reasonably safe number for iron head, and open chambers.
Options:
- Head gasket; would have to be in the range of .125" thick to get this under control. Cometic does make them that thick.
- Cam: Even with an advertised duration of 300 degrees and wide LSA, the DCR is still in the mid 8's so unless this is a pretty serious race-only engine with an even bigger cam, that is not going to do it.
- Pistons: the probable choice at this point
OP, what is you planned use for this car/engine? That will drive the general cam selection which will drive the piston selection and SCR/DCR.