Getting a Single Turbo DCT with a full M3 conversion tuned

[dyezak]

This was a journey that took forever. Once I got my Doc 6266 installed on my M3IS (335IS w/M3 DCT and 3.15 LSD drivetrain conversion) I took it for one drive, and found that I had a problem. I (yes it was me) bent the shaft on my turbo. I had to send it in for PTE to fix it. It took 3mo to get fixed. Once I got it back I have been constantly fighting misfires. Turned out I had a problem with my #4 coil connector. Finally fixed that and then I have been fighting wheel spin and extreme ignition retard because of TQLM #4 and me constantly banging the rev limiter in gears 1-3.

This morning I got a good clean pull on 4th gear after warming the tires up. If @doublespaces wants to make this thread one of his snazzy integrated log upload testing threads I'll be all over that.

https://datazap.me/u/dyezak/log-1541946148?log=0&data=2-3-22

 

[dyezak]

 

[LMB335is]

Are you just using your old pre single tune right now or did BQ toss you a base ST tune? I take it you're still waiting on IKM0S too?

 

[dyezak]

BQ is working with me and did a base map.

 

[yuli8466]

how can your hpfp rail pressure reach 3500 psi in the middle range?? do you install vtt shotgun ? your hpfp is maxed out in 17psi

 

[dyezak]

Yes, I'm running a VTT Single Shotgun right now. Got a map revision loaded this morning and drove the car to work for the first time this morning in over 6 months.

 

[Jake@MHD]

I've got something for you both today

 

[dyezak]

My car was sitting for about 6mo not running. I think my serp belt slipped due to being dirty on that first run leading to HPFP crashing to 1300psi. This second log (after a tuning revision) didn't have the same HPFP crash, though it was still a huge dip up top (down to 2400psi).

https://datazap.me/u/dyezak/log-1542046669?log=0&data=3-22

I also had to lift in the middle of that pull for a split second because I went over a slight crest in the road while WOT in 4th gear at 5500rpm and the car pulled sideways because it lost traction. My poo will now be used as a diamond enhancement stone for my wife's anniversary ring....

 

[Dreyo27]

wait you actually used the m3 DCT tranny that bolts up to the S65?

 

[dyezak]

wait you actually used the m3 DCT tranny that bolts up to the S65?

The M3 DCT and 335is DCT are exactly the same except for the bellhousing. I converted everything else to M3 surrounding the DCT.

GWS, Shift Logic, Rear Diff, Driveshaft, axles, DSC, and will be doing the DME soon since @jyamona got that wrapped up for us. This gives us full control of the shift patterns, full launch control, no DSC intervention during launch, etc... Just like an M3:

 

[Dreyo27]

Thats awsome. How much TQ do you think it will handle?

The F80 guys flash the DCT with the M4 GTS software to increase the clamping force and hold more TQ. Interesting to see if the same logic applies here

 

[Schurter]

Do you feel this setup will bring low et in the 1/4.

Has there been a dct 335 in the 10s yet ?

 

[aus335iguy]

Do you feel this setup will bring low et in the 1/4.

Has there been a dct 335 in the 10s yet ?

Not to my knowledge. This would be the one if there’s any! Good going @dyezak !

 

[dyezak]

Thats awsome. How much TQ do you think it will handle?

The F80 guys flash the DCT with the M4 GTS software to increase the clamping force and hold more TQ. Interesting to see if the same logic applies here

I'm running the M3 GTS software and full controls systems on mine. GWS, SZL, DSC, DriveLogic, Rear Diff/axles/etc...

 

[dyezak]

Do you feel this setup will bring low et in the 1/4.

Has there been a dct 335 in the 10s yet ?

We had one person hit 11.0. The problem is the launch. On the 335is the LC requires traction control be enabled. That means nobody has been able to launch a DCT N54 because you always bog once TC kicks in.

That's one of the big reasons we did the M3 conversion project. With the M3 control systems TC is completely off during launch. If I keep the car and not sell it then we will put a set of slicks on to see what she can do.

 

[LMB335is]

We had one person hit 11.0. The problem is the launch. On the 335is the LC requires traction control be enabled. That means nobody has been able to launch a DCT N54 because you always bog once TC kicks in.

That's one of the big reasons we did the M3 conversion project. With the M3 control systems TC is completely off during launch. If I keep the car and not sell it then we will put a set of slicks on to see what she can do.

Do it! It's turbo weather now.

 

[Lurcher]

Need to get off the DNT and come over to 121 - no concrete walls around. Doing this in front of Classic BMW - priceless....

 

[dyezak]

Need to get off the DNT and come over to 121 - no concrete walls around. Doing this in front of Classic BMW - priceless....

That's my standard tuning/datalogging loop. I drive through city streets calmly until my car gets up to temp. That generally happens right in front of Classic. I then head north on DNT, then north on 121, then south on 75. That lets me exit off and get back on the highways over and over using the on-ramps as my WOT areas for data logging.

Back when I was on factory twins and could do a pull in 3rd gear that meant I was never really going much over the speed limit. Now that 4th is what I have to use for traction purposes......well.

Guess a set of Drag Radials is coming soon.

 

[dyezak]

For those that know about DCT tuning and full power shifts here is a png of one of my logs. This is still very early in the tuning process and we are working on fueling still, but look at the 4-5 shift. I stayed WOT during this shift, which only took 0.13sec (compared to 0.400 on a 6sp or 0.600 on a xHP Stg3 6at). During the shift you can see the orange (boost) line only slightly dips losing 2psi during the shift and fully recovering as soon as the next gear is engaged. Also, the yellow (timing) line shows a slight dip from 11.2 to 3.4 and back to 10.5 immediately as soon as the shift was done.
Lots of tuners can tune fuel and ignition under the curve. The skill here is maintaining that during the shift sequence. This is what a shift should look like on DCT. In all honesty this shift was a bit slow at 0.13. I've got plenty logs showing 0.08sec shift times. But other than the slightly lazy shift this is perfect. Boost is near flat through the shift. Timing drops just enough for the clutch packs to disengage and engage. And instant boost and timing immediately after the shift.

 

[aus335iguy]

Awesome stuff - This is a Bq tune ?