My cousins ford diesel runs 32 lbs of boost. Unreal. When it blows your gonna see it space

 

I would be shocked if ANY manufacturer has code in the ECU to advance timing beyond 91 or MAYBE 93 octane in the US. It would be really cool, but I haven't come across that being the case.

 

They don't sense octane. They have a max advance and back down according to knock sensors. You can actually gain MPG on these systems by using lower octane and driven accordingly than using recommended 93 or whatever. I found that to be the case on my 06 Cayenne S and my wife's Audi. Yes when pushed it seem that the sensors do their job, no ping but slightly less wot power.

 

I used to buy so much 100LL avgas from the Pomona Airport (the one across the street from the dragstrip where they hold the NHRA Winternationals) the guys who worked there gave me the code to get in the gate so I could drive my 1967 Buick GS California 340 (high compression) right onto the tarmac in the wee hours of the morning on Saturdays (this was before 9/11.) Avgas however is "dry" and tends to eat fuel lines, so what I would do is add a bottle of Marvels Mystery Oil straight into the tank. My GS loved the mix and ran awesome, much better than on 91.

For my 10-second 1987 Buick Grand National I use VP C16 which is leaded and has a motor (not gas pump (R+M/2)) octane of 118. I converted the car to use a Bosch or Denso three-wire heated O2 sensor (stock '86-'87 Turbo Buicks only run one unheated O2 sensor) from a '92 5.0 Mustang application; these hold up really well-- usually about 6-8 months-- afterwhich the O2 cross-counts start to drop off (I use a laptop to log data) indicating the sensor is getting lazy and that it's time for replacement. I tune the car conservatively and run a PT70 turbo pushing 24 psi boost on a mildy built stock compression 3.8L V6 (231 CI), staged dual in tank fuel pumps, factory fuel lines and a big intercooler; VP C16 isn't cheap at $13/gallon, and in race mode my car get 1.25 gallons/mile. For my other Turbo Buick I run crappy CA 91 octane, but augment it with a hidden alcohol injection system which uses a mixture of Marvels and denatured alcohol that I buy in 1 gallon cans from Ace Hardware; this allows me to run 21 psi boost on a relatively small "old tech" TA-49 turbo and high mileage (180K) engine. Some of the really fast Buick guys go all out and run VP Air/Race, which is what they use in P-51 Mustangs at the Reno Air Races.

 

+1
High octane gas actually ignites with more difficulty at normal advance and compression values. You can exploit its properties only in an engine tuned to that purpose, i.e.: high compression and good ignition advance under high engine load, otherwise it's wasted money and engine performance may actually decrease.

 

Same thing?

Is your wife's Audi boosted or NA? There are boosted motors that immediately go into limp mode with sub-91 octane.

 

Well kinda not really same thing but we are on the same page. My wifes current is not boosted but her previous one was and the same thing did occur but it was the 89 oct that provided the best economy but probably not the best power. Her commute dictates we try to maximize the mpg during the week. Back in the day I hung out(tried to anyways) at some big deal V-8 engine gurus shops and some of the stuff they found out blending pump gas with other pump gas for pump gas class engines was weird. If it wasn't for the reputation that these guys had and the effort they put into finding the best performing pump gas, I wouldn't have believed it. Like mixing SU 2000(Shell Super Unleaded) with RU(Regular Unleaded) and getting better numbers on the dyno than with straight SU. Something about additive packages and the way they react with each other. I was young and just wanted the blend ratio and didn't listen like I should have to these guys. There is much more to fuel than just an arbitrary octane number on a pump. I should have paid more attention and picked those guys brains more, instead I'm sure I acted like a known-it-all kid.

 

Why waste your hard earned money on this? Your engine CANNOT use 100 Octane, especially Aviation Gas/AVGAS. It's dumping money in the engine, that it simply will not translate into anything meaningful. It just boggles my mind to think of the pure waste there. 'nuff said.

 

seems most of us on here have it to waste. how else can you explain taking perfectly good parts off a brand new bike, only to be replaced with other parts. taking off chrome parts that are just fine, to be replaced with flat black parts? etc, etc, etc. lol

 

That's why I don't have chromed side cases, no money to waste and can't see tossing perfectly good, but still expensive to buy, standard metal cases. Bet there's truckloads of good Harley parts in garages. Ought to be a Harley parts swap site, trade that chrome you wanna do in black for standard metal, plus a few bucks. Chrome has special paint needs anyway, doesn't it?