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Overkill Tuning Questions

5K views 8 replies 3 participants last post by  Joes74challenger 
#1 ·
After a long wait I finally received my tune files back from Overkill for my 2010 3.5. I loaded up the 87 tune and trans tune last night and must say this is a completely different feeling to the car. the trans funky shifting i had from 1-2 is gone finally, but i noticed this thing is all too happy to drop out of overdrive. which leaves me to question a couple of things. does anyone know if i can do any tuning to the trans program with the tuner Overkill sells? i know in hind sight i probably should have purchased the hptuner to perform this function, i can't justify the extra expense at this time.

also is there a limit to the number of times you can flash an ecm or tcm? i performed the tune steps last night with the ignition off then doubted it worked so i did it again with the ignition on (car not running) to make sure it was done properly. the thought also came to mind if i start getting funky shifts again i can always just re-flash the tcm program only to resolve the issue.

the tune i received for the higher octane says 93 octane i believe. i don't remember off the top of my head if this is an octane i cane obtain easily and would i be safe running 91 or 92(i think 92 is more common in the stations i frequent)? i don't figure a 1 octane difference would matter much but just wanted to be sure before doing so. i do generally stay with top tier stations 95% of the time but occasionally vary to whatever i can find during road trips.

another point i noticed during the programing is the handheld flashed error a couple of times during the process when i pressed buttons it wasn't expecting? anyone else seen this before? also it kept asking if i wanted to license this car (terminology might be a bit off but that's the gist of what i thought it was asking). does it ask that every time or only on the first time or two using the handheld? there aren't a certain number of flashes available for this tuner are they, then i have to buy more "tokens"?

just a couple of questions, thanks for any input anyone can offer up.
 
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#2 · (Edited)
I haven't used the device that Overkill uses to flash his tunes, but regarding the flashing of the ECM/TCM - I've flashed mine *hundreds* of times (calibration updates - not full flashes). With HPTuners, you normally only do a "Flash Calibration" - a Full flash is something that is only done in rare circumstances. So you don't have anything to worry about in terms of how many times you flash the ECM/TCM. :)

I don't think that you can adjust the trans settings, but I'm sure that Overkill will adjust the tune to stay in overdrive more often. Basically, it's setup based on speed and pedal position - and Overkill usually unlocks the TCC anytime you press the gas more than xx% (you don't want to be in overdrive when trying to accelerate quickly). But like I said, he'll be glad to adjust it for you. Only way to do it yourself is with an HPTuner (or HPTuner-like device).

WIth my car, the high-octane tune was for 91 octane - but I have a different engine (3.6) than you, so I'm not sure about the 3.5.

When flashing, I personally keep all doors shut, fans and radio off, etc - you don't want anything communicating over the CANBUS while flashing. This may be more of a safeguard than a hard-and-fast rule ,but you definitely want to err on the side of caution when writing to the ECM/TCM... You shouldn't need to purchase anything additional to re-flash (regardless how many times you flash.

Hope that helps somewhat...

Sent from my Hi10 pro using Tapatalk
 
#3 ·
Thanks for the info. also i went back and looked and it appears he's selling the HPTuners himself now (recommending them on the site). however that option isn't listed for the 3.5's so i'm unsure if i a person could use the HPTuner on a 3.5 or not (i don't see why it wouldn't work), I'm just thinking out loud at this point.

after travelling to Michigan this past weekend i started looking more closely and found 93 octane at every gas station we visited. so the 93 octane question may be a non-issue.

Thanks for the input!
 
#4 ·
Yeah, I'm almost positive that HPTuners will work with the 3.5 as well (I think I've seen tunes for the 3.5 in the HPTuners repository). The HPTuners device is a little pricy ($500 new), but it is *so* nice being able to adjust your tune to your preferences. Simple things like adjusting the shift points slightly can make a big difference. Plus you can fine tune the amount of torque management and lots of other stuff. The 3.5's aren't quite as "tunable" as the newer 3.6, but there is still a lot of things you can do. I've been tweaking mine for years now and I still experiment and tweak things! I was learning as I went, so a lot of what I've done has been trial and error - but I really enjoy being able to tweak things.... I bought my HPTuner used for an excellent price ($150 I think?), but knowing what I know now, I'd pay the $500 for a new one if I had to...

Sent from my Hi10 pro using Tapatalk
 
#5 ·
i took a quick look into the autocal program to see if i could tweak things with the programming itself and backed off after looking around a little bit. i'm unfamiliar with the program and afraid of screwing up my good thing i have going (and i'm in IT lol). so i suppose at this time i might keep looking into it but don't have high hopes at this time. after driving it in the rain i did notice throttle control was a significant aspect to driving i haven't had to do previously with this car. starting to think i may need to swap back to stock for the winter months to avoid burning through tires quicker than normal due to slick conditions.
 
#6 · (Edited)
Believe me, I was *exactly* the same as you when I first got into HPTuners - I refused to change *anything* - but as I spent a little more time doing research on the HPTuners forum and got to know the HPTuners application a little more, I started making very small, simple changes. Now I'm not afraid to change anything - as long as I have a decent understanding of the parameter I am changing (which, with the help of the HPTuners forum, isn't all that hard). Believe me, I knew absolutely nothing about tuning a car when I started and while I'm still a novice, I do feel very comfortable making changes and knowing what to change.

Also, just comparing the stock tune to the Overkill tune also helped a lot (the applications have a tune "compare" function, so you can see exactly what Overkill changed). This gives you a big heads-up as to what tunables you should concentrate on.

Trust me, if you like to tweak a car to you exact preferences, you'll absolutely love it. Like I said, even small (1-3mph) changes to shift points can make a substantial difference! :)

In the end, I actually ended up *increasing* my shift times for low-rpm/low-torque situations (so that shifts take longer instead of occurring faster) - and this has given me the super-smooth, un-noticable shifts that I've been after since I got the car. :) The overkill tune, on the other hand, does the exact opposite - he makes the shifts faster for performance (which also makes them more "noticeable"). Since I prefer comfort over all-out performance, the overkill tune just wasn't for me - but I did at least learn a lot just from comparing it to the stock tune - which helped me get my tune to where I want it to be.

I ended up increasing the shift time for low-rpm/low-torque shifts, keeping the stock shift times for mid-rpm/mid-torque shifts and decreasing the shift times for high-rpm/high-torque shifts. This gives me the best of both worlds, extremely smooth shifts when just cruising and faster shifts when I need the higher performance! :)

Sent from my Hi10 pro using Tapatalk
 
#7 ·
yeah at this point after a week of city driving it's already starting to "re-learn" that funky 1-2 shift, and a 3-4 shift it didn't use to have before. seems to occur about 2500-4k i suppose, like it's expecting you to keep into the gas harder but it needed to shift sooner than anticipated. i thought about just re-applying the trans tune again to get rid of it. at this point i'm not ready to spend anymore on another tune controller but i may change my mind after summer. i still need to buy those spyder headlights at some point as well. just blew another sylvania bulb, thought about trying phillips this time.
 
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