[_ink]

The quest for more power has exposed a weak link, one that was inevitable, however with a vast lack of information to really research about... Hence this thread.

My go fast mods are essentially FBO with RB's, TFT's, meth, E85, with a stacked JB4/MHD tune. (PI kit is standing by, ready for install)

I've experienced all the joys and nuances with the DCT, and also explored additional cooling options sparked by the dreaded 'Transmission Overheating' warning messages... First time this occurred I had the car towed, and it's happened at least 3 additional times after that. I must also state that I do not track my car, this is all street driving.

The solution to this overheating issue was David (Trebila) and his work in getting the back end flash to acknowledge that the actual power and torque being put down is much higher than stock. This took many revisions to dial in the requested load/actual load, and was now dialled in with problem free DCT operation.

I'm not one that strives for dyno queen glory rights, but I am one to make the most of what I've got. As a heavily modified 35i and the TFT's allowing more boost whilst working less harder than with stock inlets, David and I decided to turn the boost up to 21psi all the way to redline.

This uncovered another limitation... You guessed it - DCT slip in the upper rev range! A hard and fast limit as a result of hardware, not software (everything was maxed out).

I had 2 options at this point:

1. Accept this, and just be happy with what I've got - which at this stage was 356rwkw's

2. Upgrade the DCT clutch packs... The inevitable

As you guessed, I chose option 2.

I chose Dodson for the clutch packs primarily as they have a great reputation in the GTR DCT world, and a couple of members have installed these in the US with great reviews.

I also decided to upgrade the DCT pan for 3 reasons: Additional oil capacity, Improved cooling with the fins, structural integrity so I can run it without the plastic tray trapping the heat. I went with the SSP pan due to design.

So here we are, everything has been installed by the only workshop that I allow to work on my car, Advan Performance.

I'm bedding them in now, and can't wait to see how they go once I can turn it up!

[JB4-335]

Well done mate. Can't wait to see how it goes.

[John_01]

Red transmission sump looks great.
Are you going run it without the plastic under-tray, or do anything to get more airflow onto the heatsink?

[bmwheath]

Should be bangin through the gears nicely mate, hopefully no more slip

[_ink]

Originally Posted by JB4-335

Well done mate. Can't wait to see how it goes.

Thx mate, and me too!

Originally Posted by John_01

Red transmission sump looks great.
Are you going run it without the plastic under-tray, or do anything to get more airflow onto the heatsink?

Plastic under tray has been trimmed, so it will be exposed from now on - Can do that now that it's metal

Originally Posted by bmwheath

Should be bangin through the gears nicely mate, hopefully no more slip

cheers mate.

[sbce90]

Now you gotta take me for another ride. I need that sensation haha!

[DR-JEKL]

That looks expensive!

What sorta power/torque is the dodson kit rated for?

[AUSf22]

does it "bang" louder on the upshifts ?

[EB89]

Dam that's some dedication, how hard do you drive on the street!!!

[tawfeeqh]

Nice writeup - a very good point you make that there comes a time at a certain power level that you need mechanical/ hardware upgrade and not just TCU tuning!

I am also hoping Nizpro here in Melbourne end up with a reliable hardware upgrade for the ZF 6AT

[Scotty89]

Originally Posted by tawfeeqh

Nice writeup - a very good point you make that there comes a time at a certain power level that you need mechanical/ hardware upgrade and not just TCU tuning!

I am also hoping Nizpro here in Melbourne end up with a reliable hardware upgrade for the ZF 6AT

Anymore news on that? I think my gearbox is shagged.

[tawfeeqh]

Still work in progress - they'll give an update in the next couple of weeks i suspect

[_ink]

Originally Posted by tawfeeqh

Nice writeup - a very good point you make that there comes a time at a certain power level that you need mechanical/ hardware upgrade and not just TCU tuning!

I am also hoping Nizpro here in Melbourne end up with a reliable hardware upgrade for the ZF 6AT

Depending on the tune you're running, Trebila has had success with tuning the AT box for Marty who is putting down over 400rwkw's - you should contact him first to see if anything can be achieved for you.

[tawfeeqh]

Yeh i read about Marty's car. My car is not putting down anywhere near that power, however I am just thinking ahead for when i do get upgraded turbos and e85. Currently on COBB protune, however may be switching to MHD soon. I have read stacking with JB4 as another option but opinions vary

[_ink]

I may as well continue to use this as a semi-build thread on the new things that I've done..

Got this done today @ SDR Motorsport, replacing the mid section of the iPe with a custom 3.5" stainless system.

The iPe system goes from a dual 2.5" pipe off the DP's, into a single 3" about half way down into the muffler (comparison pic below)

I decided to do a custom mid section, which moved the merge to come straight off the DP's into 3.5" stainless T304 piping, with a 100CPSI Catalytic Converter with a 5" body (for extra flow).

Mad props to Tully @ SDR Motorsport for his sexy welds and a top quality system!!

P.s. He also did the muffler delete/PE mod on a forum members car.

[R32GOJIRA]

Would love to hear a sound clip of the exhaust to see what is sounds like.
Also if you dont mind, would you be able to pm me with details of the dct upgrades? Im interested to see what the cost is.
Are you running a twin oil cooler setup? If not, you might be able to add a trans oil cooler and run an external pump and lines to where a second oil cooler may be mounted at the front.

[Socket]

Nice

[_ink]

Originally Posted by R32GOJIRA

Would love to hear a sound clip of the exhaust to see what is sounds like.
Also if you dont mind, would you be able to pm me with details of the dct upgrades? Im interested to see what the cost is.
Are you running a twin oil cooler setup? If not, you might be able to add a trans oil cooler and run an external pump and lines to where a second oil cooler may be mounted at the front.

I'll see if I can get a sound clip once the new cat has worn in.

Re DCT upgrade costs, the prices of the clutch packs and oil pan are available online on Dodson and SSP's website.

Install from Advan is in the vicinity of ~$1500 which also includes the OEM DCT fluid.

In regards to cooling the DCT, this is something that I've investigated thoroughly. When I discovered that the AT and DCT's are cooled and routed in the same way, this opened up some options.

I began with the DCT pan for a few reasons:

1. Additional oil capacity
2. Finned system for cooling
3. Solid alloy allowing you to run without the splash shield without worrying about cracks - promoting better cooling/air flow.
4. Stock pan prone to leaks (on my BMW models, including the M3)
5. I was replacing the oil and had the transmission out anyway, so a good time to do it

TL;DR

The AT and DCT are cooled in the same way. We have a heat exchanger in the middle of the system (between the transmission and radiator) to assist in bringing the transmission to operating temps on cold starts.

From what I could find, there are only 2 manufacturers that produce a radiator suited to AT/DCT applications (MT's use a different radiator):

They are OEM (and equivalents) and CSF (who are very well known in the States) offering a complete Aluminium unit with extra capacity.

Thanks to some pioneering forum members, the CSF has been tested and proven to deliver results with track junkie members, who previously would go into limp mode on stock radiator, and no more with the CSF in place.

The other option, is what you mentioned with the addition of an auxiliary cooler mounted on the passenger side vent. Only recently, a forum member (AUbeast) has designed and fabricated CNC fittings to plug into the existing system, bypassing the heat exchanger to route into an auxiliary cooler with thermostat and AN fittings.

The results of this look promising so far for this to be a very viable option.

As I despise the use of plastic in the engine bay, and curse at BMW regularly for this, I decided to go down the path of the CSF radiator upgrade as it will deliver benefits to both transmission and engine cooling...

Stay tuned for more details on this.

[R32GOJIRA]

Originally Posted by _ink

I'll see if I can get a sound clip once the new cat has worn in.

Re DCT upgrade costs, the prices of the clutch packs and oil pan are available online on Dodson and SSP's website.

Install from Advan is in the vicinity of ~$1500 which also includes the OEM DCT fluid.

In regards to cooling the DCT, this is something that I've investigated thoroughly. When I discovered that the AT and DCT's are cooled and routed in the same way, this opened up some options.

I began with the DCT pan for a few reasons:

1. Additional oil capacity
2. Finned system for cooling
3. Solid alloy allowing you to run without the splash shield without worrying about cracks - promoting better cooling/air flow.
4. Stock pan prone to leaks (on my BMW models, including the M3)
5. I was replacing the oil and had the transmission out anyway, so a good time to do it

TL;DR

The AT and DCT are cooled in the same way, this is, via the lower section of the radiator. We have a heat exchanger in the middle of the system (between the transmission and radiator) to assist in bringing the transmission to operating temps on cold starts, and to bypass the heat exchanger for cooling via the radiator.

From what I could find, there are only 2 manufacturers that produce a radiator suited to AT/DCT applications (MT's use a different radiator):

They are OEM (and equivalents) and CSF (who are very well known in the States) offering a complete Aluminium unit with extra capacity.

Thanks to some pioneering forum members, the CSF has been tested and proven to deliver results with track junkie members, who previously would go into limp mode on stock radiator, and no more with the CSF in place.

The other option, is what you mentioned with the addition of an auxiliary cooler mounted on the passenger side vent. Only recently, a forum member (AUbeast) has designed and fabricated CNC fittings to plug into the existing system, bypassing the heat exchanger to route into an auxiliary cooler with thermostat and AN fittings.

The results of this look promising so far for this to be a very viable option.

As I despise the use of plastic in the engine bay, and curse at BMW regularly for this, I decided to go down the path of the CSF radiator upgrade as it will deliver benefits to both transmission and engine cooling...

Stay tuned for more details on this.

Thanks for the info.
Cant wait to see what it sounds like.
Some one has done their homework
Would you not be able to plumb an auxiliary cooler in without bypassing the oem bits and pieces, that way you could use the factory cooling with the added bonus of the auxiliary cooler?

[_ink]

Originally Posted by R32GOJIRA

Thanks for the info.
Cant wait to see what it sounds like.
Some one has done their homework
Would you not be able to plumb an auxiliary cooler in without bypassing the oem bits and pieces, that way you could use the factory cooling with the added bonus of the auxiliary cooler?

No worries mate.

I'm sure there may be a way to do this, that's how the M3 is setup. But for simplicity, this bypass is the easiest method to deliver an aux cooling solution, which is separated from the OEM system and operating on its own thermostat.

The radiator also helps with the power steering temps, which is another added bonus. Consider the fact that I am almost doubling the power output from factory standard, it makes it an easy choice to upgrade the only thing cooling the engine (and other fluids).

[DR-JEKL]

M3 dct cooler retrofit may be possible?

Love the exhaust mate looks awesome!

[_ink]

Originally Posted by DR-JEKL

M3 dct cooler retrofit may be possible?

Love the exhaust mate looks awesome!

Cheers Shane, the exhaust really is a work of art and the welds are amazeballs!