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BOZO · 11-26-2010, 10:57 AM

Be aware of the kind of pistons you order upon rebuild. 58 cc heads can give lots of compression in a 4" bore with flattop pistons. Though the cam you have chosen will bleed off some pressure on the lower end, todays gas may tend to rattle under a load with anything more than 9.5 to 1 compression. Dropping your compression a little can mean a 40 cent reduction per gallon at the pump due to being able to use the 89 octane instead of 93. All my vehicles require 93 octane and it hurts the pocketbook to feed my old big block.

11-26-2010, 10:57 AM	#5
BOZO Old School Join Date: Jan 2010 Location: Dover,AR Posts: 185	Re: Is this a good combo for engine build? Be aware of the kind of pistons you order upon rebuild. 58 cc heads can give lots of compression in a 4" bore with flattop pistons. Though the cam you have chosen will bleed off some pressure on the lower end, todays gas may tend to rattle under a load with anything more than 9.5 to 1 compression. Dropping your compression a little can mean a 40 cent reduction per gallon at the pump due to being able to use the 89 octane instead of 93. All my vehicles require 93 octane and it hurts the pocketbook to feed my old big block. __________________ #1 Project...69 Chevy swb Fleetside (Dad's truck) #2...1983 El Camino SS (Choo Choo Custom) #3...1974 Datsun truck (4.3L V6/4L60E) #4...1951 Cadillac Limo (1975 Caddy running gear) #5...1938 Dodge M38 3/4 ton Military truck #6...1968 Sportster XLCH trail bike 5 GMC & Chevy parts trucks 68 to 72 Last but not least; My 1978 Harley Davidson Electraglide (trusted & reliable companion for the last 30 years)