Leave the compression ratio as is. It's never more than 8.5:1, often 8:1, okay with mild boost. If you want 9 or 12 pounds, then go for the thicker composite gasket.
You can even go for a fairly agressive 264 or less than 280 degree cam to blead off pressure. Tip. Some older drag racers were able to bolt 6/71 blowers with 12 pounds of boost on SuperCobra Jet 428 V8's...because they had screamer long duartion cams which allowed 11.7:1 cmpression ratios without detonation. Documented evidence in a very well know 32 Coupe article in an 88 Hot Rod mag.
Tip 2:The cast iron log is heated by the exhast manifold. Murder on the incoming fuel air mix, and possibly creates a need for 93 octane in some cars, rather than 87. Any intake heating on a blow through turbo is bad. The Clifford port divider would be a brilliant addition, along with henium coating the exhast ports in the head, and then water injection as a last ditch option.
If you ever get into the engine, 0 deck the block, or add 1.58" pistons with a thicker composite gasket. In stock form, the 30 to 50 thou gap between the block face and the piston heats the ridge around the top of the cylinder wall gets hot, and possibly increases the need for a higher octane number gas.
People like Mustang Geezer and others have found they don't have to use octane boosters even with over compression ratios of about 9.3:1, althoug they did have to buy 93 octane.
Stacking gaskets is bad on an engine which has small margins around the bores. Stock, they have a minor gasket problem in long suffering engines. Modified with boost and stacked gaskets, its a dead certainty that the gaskets will blow.
The exhast closing event creates effective compression. This can create detonation under high boost conditons. The stock head breaths poorly, the stock exhast ports create backpressure, and hurt performance. On a modern, free flowing head big cams are nasty with turbos, not so the six!
Import Killer and Does 10's...no major mods, just boost!
