Why is everyone so damn cheap and wants to run on piss gas. How many miles do you put on these hot rods. 1,000 miles 2500 miles a year? Let's say 1,000 miles. $3.00 dollars per gal. 87 or $4.00 per gal. 93 I'll try with some basic numbers 15 mpg, 67 gallons so $67.00! give me a break. 2500 miles $170.00 a year. Now let's see what some real power might cost you, 10.5 -11.5 compression at $15.00 a gallon race gas so let us add about 2 gallons leaded race gas to the mix. So now we have added lead to unleaded and up goes the octane and we added some 112 to the mix. So maybe 97-98 octane. 16 x 4 + 30 - 8 = 86.00 for 18 gallons. So this adds up to less than $120.00 per 1,000 miles driven if you were using 87 octane and about $52.00 if you were already using 93. Now try your exact same combo but go from 8.5 to 11 to 1 and you will think you just bought a whole new car. Lots of other equations can go into this but you get the idea.