The E46 M3 with the SMG is not *as bad* as people make it out to be. The CSL 255 flash for the SMG improves the SMG to where it actually is a reasonably enjoyable transmission. #shocker /End.
Okay, so while that isn’t the actual end of this post, it pretty much sums up the fact that every SMG M3 should have this tune because it is worth the $95 (at the time I got it done) that my favorite shop, European Auto Source(EAS), charged me. Recently, I purchased a Mystic Blue 2004 M3 with the now infamous SMG transmission. I did have some experience with the SMG before, but really, I bought it with the intention of manual swapping it ASAP. Since I was having the rod bearings and rear subframe reinforced at EAS, I thought I may as well have the tune done to make the transmission more tolerable because at this point it I wanted it out, and I knew it will be awhile before I do the swap.
After getting my car back from the shop, some of my complaints on the factory SMG programming were either resolved or at least minimized to a point where manual swapping is now almost at the bottom of my list of things I want to do to my M3. Yes I actually kind of like the SMG now.
“OMG, how can you like the SMG? (Insert barf emoji’s, thumbs down emoji’s, etc, etc)”
The fact is that most people who say the above either haven’t extensively driven SMG cars, haven’t driven a CSL flashed one, and/or are on the SMG hate bandwagon because nobody wants to admit the SMG (despite its many faults) is not that bad (ask me how I know). I keep saying “not that bad” because: No, the CSL flash is not a be all end all cure to the SMG’s problems, but it really makes the SMG decent. No, the SMG will never be as fast as a DCT, or as smooth and quick as modern day ZF8’s (it’s properly quick though with a shift speed of 0.08 seconds). No, the SMG still isn’t as good as a manual M3. And Yes, the SMG is more costly and more of a headache to maintain than a manual.
But now with the CSL flash, clutch engagements are smoother. Particularly low speed and take off clutch engagements. Before it would judder a little, so if you were say making a right turn into traffic at an intersection, you would have to make sure there’s enough time after the car passes for the clutch to engage and for you to turn, otherwise you’d have an angry driver behind you (ask me how I know… or really any Ford Focus owner with the Powershift Automatic). With the CSL flash its a quick jolt and you’re off.
While slow speed/around town shifts are smoother, there is still some adaptation needed to prevent you from getting whiplash between shifts. This is my least favorite part of the SMG because getting used to the SMG by letting off the gas is the equivalent of getting used to Arizona heat. You don’t really get used to it, you just learn to stay inside with the A/C on (I lived in Tucson for 4 years).
Launch control is awesome and raised to a 4500 RPM limiter (hope your subframe is braced!).
Best of all is rev matching. Without the CSL flash, the SMG would only rev match if you’re on the gas. Which is great if you’re trying to downshift to pass but not so great if you’re braking as it feel like its gonna send you through the windshield. Post flash, it will rev match on or off the gas so you don’t have to fear for life or limb.
And this brings me to why I began to really warm up to the SMG even though it’s still a derp around town. At full chat, attack pace, whatever you call it, the SMG comes alive. In its fastest shift setting (shift setting 6), shifts are fast, snappy, and responsive to the paddles. 0.08 seconds shift speed is faster than an f430 (0.15 seconds), an isF (0.1 seconds), and not far off from the e9x M3 DCT’s shift speed (0.06 seconds), and way faster than most humans. And the shifts are brutal, like a WW2 battleship firing its 16 inch main batteries. Pull the wheel mounted paddle and the gears are hammered together with a kachunk. Probably not good for the longevity of the transmission but it makes for great fun. Downshifts are rev-matched beautifully with the CSL tune, and it’s just fantastic. It’s a unique experience to feel this transitional tech between slushboxes and DCT’s.
So yes, get the CSL SMG flash if you have an SMG. And for others, don’t discard the SMG transmission. As a Dan Tacket, a commenter on Bimmelife’s post noted: “SMG is the second-best transmission for the E46 M3. It’s not as good as BMW thinks, but it’s also not as bad as non-owners say” (Bimmerlife.com).
