TallMartin

OMG




However, for $8.999 per gallon, I would have been massively disappointed if I had noticed nothing...

gk1

Which tune are you running? It's not in your signature.
APR only shows a mild 20HP increase on 100 octane vs. 93.
One of the reasons I have to try it...

IknowHuhA6

One doesn't need a tune to gain power increases form higher octane gas. A tune pulls maximum power out of the higher octane but you still get better power with just the gas alone. The race gas higher resistance to detonation allows the car to run higher timing and a better air/fuel ratio for increased power. Our modern computer controlled cars can adjust to the better octane and re-map its fuel curves, timing, and AFR. I imagine the boost bleed-off will also be less since the car will calculate that the threshold for detonation has been raised.

There are plenty other limiters for an engine's power so depending on these, there will be some increase, and much more with a tune that removes these power restrictions

gk1

Not really. There is a max to the stock software. If even with a tune specifically designed to take advantage of 100 octane you only pick up 20HP. How much room do you think there is in stock form? That's like saying a motor which only requires 87 will be a rocket on 93...simply not true.

TallMartin

no tune

I just thought the car felt and sounded noticeably more powerful. However, my butt-dyno did not render a precise reading...

IknowHuhA6

I probably didn't explain myself correctly. No the car won't pick up major Horsepower with higher octane in stock form, but you will gain a an increase in performance. Yes stock software restricts power. I have been building and tuning GM engines as a hobby for past 15 years so I'm well aware of how the dynamics of an ECU's build power. However I have no clue on the specifics of how Audi's ECU works. The concepts however for building power are the same, just probably more efficient.

Going from 87 to 93 and expecting a rocket ship is an exaggeration that in No Way I meant to imply.

gk1

If 100 octane specific tune designed to extract maximum performance gains from 100 octane fuel only nets 20HP. Then any possible very minimal gains from 100 octane on the stock map certainly wouldn't warrant the use of the above pic. lol
I will concede one exception and that is if the OP is in a state where the highest pumpgas is 91, or god forbid running 87, then by putting in 100 he is finally getting the full potential of the stock program.

IknowHuhA6

LOL, oh come now, I thought it was funny and a great way to start the thread.

Yes power isn't easy to come by. It takes alot of different combinations to get slight increases in HP & Torque.
The internet is full of questionable information by both informed and uninformed with no proof or experience, but I did find an article on higher octane fuel from a long-time connoisseur of hot-rodding.

I think this helps prove both our points valid and paints more realistic picture.

Fuel Rating - Octane Comparison - Dyno Tests Graphs - Hot Rod Magazine

TallMartin

note that I was going from 91 to 100 octane. small wonder that the engine sounded and acted differently

gk1

Perfect. Thank you following and clearing that up. Makes more sense now. Have fun.