I've searched for this but couldn't find anything.

I just averaged 29.2 MPG with my new intake, driving habits = I still think I'm a race car driver. lol.

I usually fill up using 87 octane, my dad (who is a ASE mechanic and knows A LOT) said that by using 91/93 octane gas, even though its more expensive (usually $.10-$.15/gallon higher) would pay for itself the first tank.

Then my grandfather (my dads dad) tried it in his 2002 Ford Ranger and nothing happened except he wasted a few dollars (he thinks).

any input on the situation? if no extra MPG, does it keep the fuel line clean or anything like that? I'm sure there is a reason its a bit more expensive.

btw, don't laugh at me because I think I'm Ricky Bobby. I wanna go FAST!!

Thanks in advance!