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VMS tune

4.1K views 28 replies 15 participants last post by  Agose25  
#1 ·
Just installed the AFM ECM 93 octane and Stage 2 TCM tunes. Drives so completely different :) No real chance to play beyond one run to ~60 in D and one in sport mode. Certainly didn't expect the tires to break loose like that with ESC on! I plan on exploring tomorrow on the way to work.

One thing I noticed (not sure I like it) is that in drive when decelerating it feels like old school compression braking...but I do like the fact that I can jump right back into the throttle after slowing to a near stop and it takes off with zero delay.

:driving:
 
#2 ·
Can you elaborate on what you mean about decelerating? I've had the VMS tune for 3 years and I have never noticed a difference between stock tune and the VMS ECM/TCM tunes when it comes to slowing down in a gear.

There are many things that may be affecting what your referring too. Perhaps the sports mode is keeping the car in the appropriate gear and you just feel it more now. Or maybe the car hasn't adapted to the new tune completely yet so it feels different.

I'll wait until you elaborate more on what gear and mode you are in regarding your decelerating comment.
 
#28 ·
Yes - I think the OP was refering to the fact that if you are sport mode the car does not immediately upshift after you go hard on the throttle, but instead stays in the last gear....so if you let off the gas, the gear will actually slow the car, compared to normal mode, when it would upshift immediately.
 
#4 ·
Have you tried stage 1 tcm tune. The stage 2 is pretty aggressive.
 
#5 · (Edited)
Pending today's results I'll do that next but I wouldn't expect a difference in normal mode since both stage 1 & 2 feature a 50% torque management reduction.

Edit: Totally different behavior today. Part throttle upshifts are moderately more firm than stock...full throttle :) Downshifting while decelerating issue is gone. Posed a couple of questions to Steve regarding refining the TM for part throttle in normal mode and AFM.
 
#6 ·
Like I said above, probably just needed a little more time for the car to adapt. After I do my VMS tunes, I don't feel like my car has it all dialed in until about 3-4 hours of total driving. Glad you're good to go though.
 
#7 ·
Totally happy. Haven't launched without stability control yet but it seems to overwhelm the car's best efforts to slow me down.

I've gotten the new file from Steve to expand the AFM parameters a little. Not sure how much better it will get but my goal is to be able to cruise reliably at close to 80 with AFM engaged.

Next step is making it sound like my Denali...nice solid rumble. Really leaning towards the Kooks package with the SLP powerflow axle back as long as it doesn't drone.
 
#8 ·
Do both the stage 1 and 2 TCM tunes feature a 50% reduction in TM? Has anyone experimented with TM above 50% in normal mode?

Works really well if you're driving hard under dry conditions but in the wet the downshift is severe enough to completely break the rear loose under 3/4 throttle. Tires are Conti DWS in great condition (for now haha).

I'm thinking about asking Steve to make a tune that's almost normal in "normal" mode and keep the 50% in sport/manual.

What do you guys think?
 
#15 ·
...I'm thinking about asking Steve to make a tune that's almost normal in "normal" mode and keep the 50% in sport/manual.

What do you guys think?
The Stg1 TCM tune was harder than I liked and I was spinning hard on the 1/2 shifts at the track so I had Steve set the TM to 75%. The car still chirps under aggressive throttle, but is near stock under light throttle. Sounds like what your looking for.
 
#10 ·
I've got the stage 2 tune on the car in the non-winter months and it's my daily driver. I LOVE IT!!!!! During 'normal' driving the tune is there but not offensive...during aggressive driving it's a whole different car.

I may have to switch down to the Stage 1 with the new differential...have not had the chance to try it on a dry warm road yet.
 
#13 ·
^^^ when's that sale end on the tune?
 
#18 ·