Anyone notice a difference running 93 octane in your v6 ?
 

I only get 18.5 MPG with my 2LT V6 A8 so I always get the 87 octane.

Last week I was right at empty so I tried $20 of 93 octane to see if I could
feel more snap.

I couldn't tell any difference from 87 when flooring the car with in sport
mode with traction control turned off. It felt the same to me.

Anyone notice a difference when using 93 octane ?

Before I did any modding I put 87 octane in my car 1 time.. I heard pinging ( Detonation ) and never put it in again.

So there are 2 tables your ECM runs . A high octane Table and a Low Octane Table.

The timings on the low Octane table are lower then the high octane, However your ECM will only switch over to the Low Octane Table if it detects X amount of spark knock events.

So its entirely possible you are not getting any spark knock with the 87 you are using and your car is just staying on the high octane map table ( Kind of Unlikely ) But possible I suppose.

The other thing is Higher Octane gas burns cleaner. Even though Direct Injection engines do not have gas running directly over the valves it still plays a small role in keeping them clean by burning clean. The valves will need all the help they can get to stay clean and not get all coked up. Run Good synthetic Oils .. Penzoil Ultra, Castrol , Amsoil and high octane fuel and you may never need a valve job.

Or just get a catch can from Tracy Lewis.

Also where you at in Florida ?

Dustya, did you hear the pinging while you were outside of the car and it was idling
or when you were driving it? I never notice hearing any pinging but I'll try to listen
for it now. I'm in Orlando.

How much should Catch Cans cost if I want to have one installed? I never knew
what they were until you mentioned it and I YouTubed it. Why the heck don't all
manufacturers install them on their sports car lines?

Premium fuel does NOT have any benefit unless your car has been tuned for it. The V6 has not been tuned for it. The I4 and V8s have been somewhat tuned for it as premium is recommended, but not required.

Here's a study AAA did on premium fuel when a manufacturer has recommended it, but not required it. http://newsroom.aaa.com/wp-content/u...rt-FINAL-2.pdf

Yup, no diff....11000 miles on 87, never any pings.....runs great, in the 93 tanks I’ve used, I can’t tell a damn bit of diff........love that is engine is tuned for 87.......

The engine is tuned for both or it would only contain one timing map.. There is a literally tables called High Octane and Low Octane timing table.. Its designed to use the Low Octane when using 87 and 91 and High Octane when using 93.. There are things built into the stock tunes that vary what your ECM is doing based on Octane.

As for the pinging Questions above yes when I ran a tank of 87 I would get sporadic pinging you could hear in the cabin on tip-in/Take off you could also very specifically feel the performance loss when it happened due to the engine pulling timing for the knock. Like i said after that never ran 87 again. Could have been bad gas could have been the car not being used to 87 ECM have learning functionalities as well for fuel and by changing up the octane you are changing up the habits and the computer has to relearn.

There is long term fuel trim learning
There is learned knock
as well as other things..

I am by no means a professional tuner or anything close to it but I understand the inner workings of our Computer pretty well at this point.

Also this time of year you will notice less difference between the AKI of the fuels because its cooler outside so your intake temps will be down and the fuel is less likely to spontaneously combust causing knock.

How much difference in performance I cannot tell you but 93 is definitely safer for your engine if you are running it hard.

Thanks Glen for verifying I'm not the only one using 87 without hearing pings.

Thanks Dustya. I don't doubt anything you are saying. I just don't hear pings on
my car. Maybe they are happening and I don't notice that they are happening.
I am too dialed into hitting the redline on my tach and listening to the exhaust note.

I haven't read through everyone's posts but personally... almost no difference. I noticed a much bigger difference betwen 87 and 93 on my 5th Gen V6 than I do on my 6th Gen.

There is a "slight" and I mean VERY hard to notice increase in response.. but thats about it...and premium here costs about $0.50 more than 87 octane... so I just don't see the point. I only use 87 and have had no issues nor have I had any points where the car felt sluggish or pinging or unresponsive. drives exactly the same.

Edit:

Quite interesting to see people here running 87 Octane and getting pinging. I'm very surprised by this as Ive never had this issue and have succeeded up to 47 MPG on a road trip using 87... yes..thats not a typo.. a V6 A8 at 47 MPG.

For those having issues, where are you geographically located? Elevation plays a BIG ROLE, the mountain states generally recommend higher octane.

47 MPG ?
How How How ???

When I do a highway drive from Orlando to Tampa, I try to keep it in V4
mode and nurse it along but I always slowly lose speed and I end up giving
it more gas (goes back into v6 mode) to get it back up to 55. It's near
impossible to keep the car in v4 mode. Nursing as best I can I can get 32
maybe for the trip. I have the RS Package 20" wheels. V6 A8.

I almost started a thread asking people how they effectively keep the car in
v4 mode without constantly losing speed.

Im moreso with dustya on this... on a daily basis i have run 87. I dont get any pings, but im just driving to work and home. Or roadtrips. Noy really pushing the car.

However, he is correct. If anyone has done ANY logging... When you push the car, with lower octanes, you wont see timing advance as much under power. You will also notice some additional st and lt knock retard with lower octanes.

In the manual it says 87 is fine for use, but anyone doing anything performance wise can benefit from a slightly higher octane to keep timing from being pulled. The more timing a car has, the more poential of power it will produce.

This is even more so exaggerated in warmer temp months. Remeber octane is just resistance to detonation. In engines running 11.5 compression...it has its benefits in performance situations in stock trim.

Also to note, the same tables were on the 5th gens as well.

So it really boils down to what do you use your car for?

I don't know enough about these cars to comment accurately, but for our cars there are High and Low octane maps BUT without tuning the car only runs in the Low octane map. BUT (again) if you run higher octane it does produce more mid-range power because it can run more degrees of timing. The engine adds degrees until it detects knock, plus the direct injection helps with cooling significantly, but to say there's no difference from a physics standpoint considering they're 11.5:1 compression is frankly wrong. Part of it is probably the slick 8 speed auto that most of you probably have too. When you can work the engine so much more efficiently I'm not surprised if you can't tell a difference. But it's been an argument since the beginning of time - whether or not you can feel a difference does not mean the engine does not run differently. The car is rated for 335hp which means it must make 335hp at maximum and that won't change, but it does run better on 93. It becomes obvious when you're on the stock tune as you mod more and you try to run 87 vs 93. Plenty of guys on C5 have documented benefits with 93. Plenty of guys (usually without evidence) also knock what is stated.

Ultimately, it's your car and no one else can tell you what to do with it. It doesn't hurt the car to run 87, and for most people, that's good enough and it's cheaper. Probably the smarter option, realistically, especially for a stock vehicle with no intention to mod.

Dyno for reference. http://www.camaro5.com/forums/showpo...&postcount=118

It can vary, keeping it in v4 is only half of the battle, the other half is anticipating the road so that when you feather it on v4 the speed you lose is balanced by your rolling momentum... ALSO, driving it in manual mode and keeping it in 8th gear makes a BIG difference. The car does NOT deactivate DoD UNTIL you downshift, so if you downshift you have to pop it back in drive and then back into Manual mode in 8th gear and it will remain active till you downshift again... here's an example...

You're cruising in V4 mode at 65 MPH, you are looking down the road and see a decline in elevation, and right after it...an incline.. NORMALLY you would just maintain speed like the cruise control woud... ...you'll lose fuel mileage by doing this I'm afraid.. here's what you do instead...

As you approach the decline, lightly apply the accellerator while in 8th gear and let the car continue to build speed, watch instant MPG read out and make sure it stays at atleast 50 + MPG as you decline.. at the bottom of the hill you may be doing 75 - 80 MPH... maintain this with the SAME % OF THROTTLE as you had coming down the hill..as you re-climb the hill since you're not applying more gas peddle, EVEN THOUGH you're climbing the hill..your fuel mileage will remain the same - 50 + MPG while climbing, you're going to LOSE speed.. but by the time you get to atleast halfway up the hill you'll be back at 65 MPH... if you drop below a SAFE speed, go ahead and downshift, apply more fuel until you successfully climb the hill, pop it back in drive, then back into manual and grab 8th gear again to reset DoD...rinse and repeat...

I kid you not... I will take a picture of it if I must but my record is 47 MPG in 50 miles meaning I literally only burned 2 gallons of gas in 100 miles.

I don't know about the 6th gen, but on the 5th gens it was clearly shown that more timing was pulled under certain conditions on 87 than high octane. But as said above, you may likely never know it, and likely not worth it if you are driving daily. If its your sunny day/weekend ride, then I'd put the good stuff in it.

I always run 91 for 2 reasons, 1 to get better mileage and 2 for temperature.
I would not put 87 in my lawnmower.
At over $3.00 a gal. in So. California 10 cents is a low percentage and with getting more mpg it's a no brainer for me.
This is an average and every time I get on the freeway I have fun, If I take it easy I read 24 mpg average.