i just want to know what octane is best for a very mildly modded n/a 13b 6 port thanks

 

lowest octane possible.. high octane in N/A = waste of money and possibly less power (and more carbon) cause it takes more time to burn..

on a turbo it would be the oposite. highest possible to prevent detonation

 

actually s4 turbos (all s4 i believe) were recommended 87 from factory manuals.
stick with the 87 in your ported n/a. unless you did something you didnt mention, there's NO reason to run higher.

 

87 ?!.. weird..
but I was thinking about moded turbos :P

 

yea, most will run higher octane (and boost), but factory they accept, and ask for, 87. i cant quote the years, but the topic of TII octane has been covered (and debated) and someone posted a picture from the manual saying 87 for an S4. i imagine since us americans only had S4 TIIs in 87 and 88, they both asked for 87 octane.

 

87... 87... and uh... 87. I can find the image if you really want (or just scan my s5 manual).

 

i run 87 amoco/bp all the time

 

corn gas?

 

i guess? i dunno, runs fine on it