Originally Posted by jkingof9561
yes am rebuilding my 87 camaro,and am planning on swapping the original 350 engine v-belt block stock bore that already gave everything it had... for a 1991 350 2 bolt main block bored 40 over with hyperutectic flat top piston approx. 10.3:1 compression ratio with 64cc, and dress it up with original tune port injection,and my question is...??? the compression ratio would go up and boost a little more power to at least 10-20hp with a double roller timing chain...??? is it going to be more fuel efficient...???any suggestions...???
Efficiency goes up about 4-5% for every ratio gained in compression. Fuel cost per gallon goes up about 9% between regular and premium. Just messing with the numbers looks something like this:
If the 8.3 to one engine gets 15 mpg, then the 10.3:1 engine then gets 16.2.
20 gallons of regular at $3.75 a gallon costs 75 dollars and the car goes 300 miles.
20 gallons of premium at 3.95 a gallon costs 79 dollars and the car goes 324 miles.
Dividing all this gobblety gook out; you get a per mile cost of 25 cents with 8.3:1 compression and regular gas, while it only costs .24 cents per mile with 10.3:1 compression and premium gas.