Unless the engine is zero decked with two valve relief pistons and thin head gasket, it's probably down around 8.5-8.8 to 1 compression, could be even lower than that.
In an case, the 87 cc heads are not the "hot" ticket for the 400 right to start with. Huge runners, big cam, and low compression aren't going to produce a 1hp/cid engine with tons of low end and mid-range power.
You need at least 10 to 1, near 11 to 1 would be better, to effectively use the RAIV size camshafts. The problem with using smaller cams with the lower compression ratio, is that you are not utilizing the potential of the big runner Edelbrock heads.
+1 for the previous post. A 4.21 or 4.25" stroker kit would be the best option, IMHO. This would cover the compression ratio deal, and allow you to effectively use the cam you have already chosen......Cliff
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73 Ventura, SOLD 455, 3740lbs, 11.30's at 120mph, 1977 Pontiac Q-jet, HO intake, HEI, 10" converter, 3.42 gears, DOT's, 7.20's at 96mph and still WAY under the roll bar rule. Best ET to date 7.18 at 97MPH (1/8th mile),
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