[l1tech]

Just a quick question here...what is the compression ratio on a 327/210? What will the compression ratio change to, if at all, with 64cc combustion chambers?

[JimM]

The "advertised" comp ratio of a 210 is 8:1 (with 76cc heads)
Going to 64cc heads will raise it to 10:1 (advertised) in both cases, reality is probably a lil lower. The new heads will also have much bigger prots and intake valves, and I know from experience they will REALLY "wake er up!"

[pdq67]

I figure 8 to 1 CR. with a 76 cc head is about right..

A 210hp/327 is only 8.75 CR. stock, but I figure it had a 70 cc chamber head on it??

Only thing is that ROSS Racing Pistons CR. calculator figures it at 8.94 CR. with .020" thick shims vs .038 composites at 8.61 CR. so I don't know?

64 cc heads with .020" thick shims create's 9.55 CR. and the .038 composites create 9.16.

Anybody else know what pistons a 210hp/327 had in it?? Flat-tops with -5 cc, 4-valve notch?? And shims or what??

I know the info is here somewhere??

pdq67

PS., info I used; 4.00"b x 3.25"s, down-in-the-hole = .025", .020" and .038" headgasket thicknesses and -5 cc valve notch volume on true flat-top pistons.

[JimM]

the 210 (and the 275) came with 4 eyebrow flat tops, -7.1 cc's.
And I think you're right, Paul, the advertised comp on the 210 is higher than the 8:1 I said, maybe 8.5? The stock heads are 76cc.

[l1tech]

You guys are just a wealth of knowledge, thanks much