[Mike_6.4Hemi]

I know that the procedure to reset the MDS calibration is well documented. My SRT has reached the point were it will only go into ECO mode when I take my foot off of the gas. I probably confused the engine management with my truly Dr. Jekyll and Mr. Hyde way of driving. ha

I'm going to get a "track day" some time this summer, and want to get the car in its best shape for that run, so I figure that the way the car is reacting to my driving style might have caused a de-tune.

The last step involves clearing codes. 7) Hook up StarScan and clear DTC's

I haven't tried the other steps, but I'm guessing the "clearing codes" part is a necessary step (?). What is the CHEAPEST way for me to be able to clear codes? I'm not trying to do any fancy tuning. I have to imagine that a StarScan is massive overkill for my purposes.

I'd imagine that someone will try to talk me into a StarScan, so here's additional info... I've been into cars for quite some time, know how to tune an pre-computer car quite well, and I'm a computer programmer, so dealing with the computer doesn't scare me at all. It's just that I've not taken the time to learn anything about computer mods. Sell me on the idea.

Related question - in prep for this track day, I planned to fill up with some 95 octane "racing" gas (I gather that's the optimal for a stock Hemi from what I've read here). 110 octane is available at the same location, but that is overkill from what I've read. Should I do this MDS reset right after doing this, and drive the heck out of it until my track day?

 

[Nuke]

Cheapest way to clear codes is to unhook the battery for a minute and then hook it back up.

Next cheapest way is to buy a $20 ODB-II scanner from Walmart. They will clear them.

The 95 octane will be good for a summer track day. If it’s a stock tune, it’s tuned for 91 max, but most premium you get is stale anyway. So with the additional octane necessary to deal with a hot track day, 95 will be perfect.

110 is overkill, and the engine wouldn’t be able to take advantage of the extra octane without a tune adjustment anyway.

 

[Rockster]

I know that the procedure to reset the MDS calibration is well documented. My SRT has reached the point were it will only go into ECO mode when I take my foot off of the gas. I probably confused the engine management with my truly Dr. Jekyll and Mr. Hyde way of driving. ha

I'm going to get a "track day" some time this summer, and want to get the car in its best shape for that run, so I figure that the way the car is reacting to my driving style might have caused a de-tune.

The last step involves clearing codes. 7) Hook up StarScan and clear DTC's

I haven't tried the other steps, but I'm guessing the "clearing codes" part is a necessary step (?). What is the CHEAPEST way for me to be able to clear codes? I'm not trying to do any fancy tuning. I have to imagine that a StarScan is massive overkill for my purposes.

I'd imagine that someone will try to talk me into a StarScan, so here's additional info... I've been into cars for quite some time, know how to tune an pre-computer car quite well, and I'm a computer programmer, so dealing with the computer doesn't scare me at all. It's just that I've not taken the time to learn anything about computer mods. Sell me on the idea.

Related question - in prep for this track day, I planned to fill up with some 95 octane "racing" gas (I gather that's the optimal for a stock Hemi from what I've read here). 110 octane is available at the same location, but that is overkill from what I've read. Should I do this MDS reset right after doing this, and drive the heck out of it until my track day?

Really the engine and transmission controller will quickly adapt to your track driving. Have you ever after a time driving through town then come to the freeway and given the engine lots of throttle and had the engine react like it didn't get the message?

For all my OBD2 cars I have driven a hundred or more miles at a steady speed on the freeway then get a chance to open 'er up and no engine has acted like it wanted to not comply. The engine controller is specifically designed to deliver the torque requested by the driver via the gas pedal. Why would this be not be done just because before you requested full power you had not been requesting full power?

And the flip side is when one pulls off the track and cruises through the pits does the engine controller insist on not shifting until redline is reached? Does it remember the track usage and require a reset to "forget"? Nope.

Show up at the track with fresh engine oil. Bring extra in case the level drops some during the day. 95 octane is good. An engine's octane requirement goes up with age so 95 buys you some margin.

As Nuke pointed out 110 is overkill. In some cases though even if the octane rating is way above what the engine requires high octane gasoline, racing gasoline, has other attributes which can improve engine performance on the track besides the elevated octane. But the word is most of the race track gasoline appears to only really offer higher octane nothing more. If you were at the track often it might be worth it to try a "pure" tank (as pure as it is reasonable to arrange it) of 110 then compare how the engine runs vs. with even 95 in the tank. If you find the engine benefits from the 110 gasoline then it might be worth the cost.

If you use any racing gasoline at the track be sure it is unleaded!