I’m looking at doing the JHM ECU tune on my 2008 S6. I currently live in a state that only has 91 oct (6000ft) but plan on moving to a state with 93 octane (sea level). Can I do the 93 oct. tune with only 91 oct available?
Once you get the JHM tune. You can flash as needed. So this means you can flash to 91 when that is the fuel available. Then to 93 when that is available.
Thanks for the reply. I have never done any tuning to an ECU before so excuse my lack of knowledge. Is there any charge to switch octanes or is it included in the original price?
No reason to appoligize. We’re all there to help each other. As many have said ask all the questions you have no question is a dumb one.
With JHM there is no charge. Once and done. I’d suggest the TCU as well as that makes a pretty big difference and adds to the overall experience. As for switching between tunes. You can switch from 91 to 93 with no up charge. Now they don’t want you flashing each week between the two. The JHM tunes are adaptive so you can flash the 91 and still get benefit form a 93 octane fuel add. So I would run the 91 tune until you have a steady supply of 93. Even still if you run into a case you only have access to 91 octane on the 93 tune. You can run the lower grade fuel but you don’t want to make that a long term thing.
Sounds good, thank you for the advice. I have heard about JHM’s TCU tune but do not see it listed on their website. Is it still offered? Do I need to call them for pricing?
I have no idea how I couldn’t find that on their site, thank you.
If I understand correctly, you do the tuning for JHM?
After the tune is there a difference between sport mode and regular Drive?
Also if I do the ECU tune now can I do the SAI delete later on?
There was a small fee to change to SAI delete for me, but I added it years after I got the original tune, so I’m not sure if they would charge you for adding it later.
Thanks for the response.
I just searched for TCU on the site 
Me? No. I’m just helping by getting my car tuned over and over again and send back logs of the car afterwards.
However I do load the tune by myself( like everyone else) with the great windows app JHM have developed.
So it suuuuuuper easy to update it.
At one point I f***** up and the update died half way.
Car wouldn’t start, VCDS couldn’t see engine and ECU’s.
No problem!
Reloaded the original ECU file from JHM server via their app and when it was done just reloaded the new tune.
Voilà!
I live in Denmark so for me this scenario was the scariest thing … until it happened.
Where are you located?
D and S feels the same as now, but on steroids.
Well D is the same if you drive slow and easy, but when you step on it, it wakes up.
Hard to describe but easy to feel.
BTW
See @Woxxman’s video on my car here: https://youtu.be/e8ANuy0VVSE
If you see at 22:03 you can see the big difference when my car does 1st to 2nd gearshift.
It just kicks forward!
Sorry, I was asking Count Vohn if he did tuning for JHM.
I have seen several of your threads and the Woxxman video with your car. That video was great. I like your exhaust you made. I have been thinking about going the same route and making my own exhaust. I’m pretty good at TIG welding.
I’m in the USA so support with JHM is not problem.
I installed the TCU tune recently and at the same time reflashed the ECU. When I did the ECU I did not see any options to select 91 or 93 tunes and I also did not see any option for the SAI delete tune. When I tuned my ECU the first time a few years ago on their old software system I did have those options. So are the 91 and 93 tunes even still a thing?
On the new server is the 9x files. It used the ECUs ability to adjust for octane. So it works for both 91 and 93 but NO LESS than 91.
If you get both the ECU and TCU at the same time you get access to the other files but I think the latest versions of SAI and No cats are different and have been updated.
another question–has anyone tried to flash from a Mac running windows on parallels?
I haven’t done any flashing of tunes but Windows via Bootcamp is how I run VCDS on my Macbook Air and it has never let me down. This gets the Windows installation closer to the bare metal rather than relying on virtualization of which sharing hardware between host and guest could add complications and in my opinion would be more reliable.
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Good point. I still have an old Intel macbook. But it’s battery life is so 2010s