The last thing I want to do is start a greate debate about octanes. Having said that, I read with interest a post last month about someone who switched from 92 octane (the U.S. rating) to 89 and experienced a 4mpg increase in mileage. While I've never been displeased with my 89 GLi's mileage, it wasn't on par with the 30mpg I'd heard other a216v owners getting.
Another thing I should note is that my mfa seems to indicate about 2mpg less than actual mpg. I'm not sure if this is just how my engine is tuned, a small vacuum leak, or what. For example, my last tankful, the mfa reported 24.3mpg for the entire tank (I reset the "2" side of the mfa every fillup) and actual was 26.3mpg. Anyway, I have always run 92 octane and have my timing set to 6degrees. I've also been running Redline F1 injector cleaner concentrate over the last 10-12 tankfuls. My mfa usually shows ~25mpg city / 27 mpg highway. This morning, I put in mid-level octane gas (I believe 89, with plain-old unleaded being 87). On my 25 mile commute, the mfa read 28.7mpg! and this is in stop-n-go, dallas rush hour traffic. On my return trip, it reported 30.6. There was no knocking or pinging whatsoever. I'll have to wait until I refill to see what my actual mileage is, but so far, I'm impressed. I thought I would never run anything but super in my Wolfsburg, but if it doesn't complain about 89, I think I'm going to try it for a couple months, especially if 89 costs less and goes farther. Question, though, would I be achieving sort of the same thing by going back to 92 octane and advancing my timing to 12 degrees? Laters, Brian 1989 Jetta GLi Wolfsburg 16v _____________ List Sponsor: http://www.netsville.com To remove yourself from this list, send mail to [email protected] with 'unsubscribe a2_16v' in the body of your message See us on the web at http://www.a2-16v.com Visit the 16V Homepage at http://www.gti16v.org
