1
Vanagon concerns / Octane
« on: September 23, 2008, 03:06:15 PM »
I'm truly baffled by how little people actually know about the different octane ratings. The higher the octane the slower the air fuel mixture burns. This is most important in High compression Engines where the risk of pre-ignition and detonation is high. Most Vanagon motors are not race engines or anything I do realize they have marginally higher compression than that of their air cooled counter parts. But in all seriousness if you are running Ultra 94 octane (if Sunoco has it anymore) in a vehicle you are not making it run better, you are making it run with less power. This is because you are putting a slower burning fuel into an engine that was designed to run a faster burning fuel.
Look at muscle cars from the 60's and very early 70's (pre-emissions) They all had high Compression engines and the had a lot better high octane gas then. Take for example a 64' Ford Galaxie 500, they had a 390ci engine with 11.5 to 1 compression ratio which made 390hp on premium fuel. That same motor in the mid 70's with emission regulation and a 7.0 to 1 compression ratio made 190-200 hp if you were lucky on regular gas.
Not to be ripping on anyone but octane boosters are over rated, if you know how the octane system works.
I've run regular gas in all my VW's with no issues for years, most of knocking and pinging issues come down to timing and motors being out of tune.
Look at muscle cars from the 60's and very early 70's (pre-emissions) They all had high Compression engines and the had a lot better high octane gas then. Take for example a 64' Ford Galaxie 500, they had a 390ci engine with 11.5 to 1 compression ratio which made 390hp on premium fuel. That same motor in the mid 70's with emission regulation and a 7.0 to 1 compression ratio made 190-200 hp if you were lucky on regular gas.
Not to be ripping on anyone but octane boosters are over rated, if you know how the octane system works.
I've run regular gas in all my VW's with no issues for years, most of knocking and pinging issues come down to timing and motors being out of tune.