not ture. I had a friend w/ a CR-VTEC running 11.6:1 compression and he ran 89 octane and it ran just fine. If he ran 87 then itr would ping. If all he's doing is bolting a SOHC VTEC head on a D15 block he's gonan have same cpmression as a D16Z6. Which I believe is 9.8:1 so he would be fine on 87 octane. Unless he's building the motor and running like 11.6:1 or higher compression. And also if he leaves it stock it'll give him 125hp and 107lb/torque @ the flywheel. Plus whatever his small hp gains from simple bolt on's.crappy sol said:yea thats 130 hp bro at the fly wheel and u gonna have to run 91 octain gass cause ur compression is bump a few points and u can prob keep up with gsr if u know how to drive