[street 335i]

Are there any upgraded parts for your zf 6 speed transmission so it can handle the 700-800 horsepower and the foot pounds of tourqe that come with it. Us poor auto boys wanna make power too.

[ragingpanda]

I would consider swapping to a 6 speed manual transmission to handle that kind of power or go to a different platform altogether.

[mweisdorfer]

Find a used DCT transmission, maybe one out of an M5.

[siloansa]

Originally Posted by ragingpanda

I would consider swapping to a 6 speed manual transmission to handle that kind of power or go to a different platform altogether.

+1

[nicky dj]

Originally Posted by mweisdorfer

Find a used DCT transmission, maybe one out of an M5.

mw - is a DCT out of a IS is a straight swap for swap with the z6AT?

[mweisdorfer]

Originally Posted by nicky dj

mw - is a DCT out of a IS is a straight swap for swap with the z6AT?

Well, there's a DIY or two for this, should you take one out of a 335is. It's not cheap. Probably run you $3,000.00 or so. However, it's really, really difficult to beat the speed in terms of shifting a DCT offers. This transmission, like the 6AT, is bulletproof. I'm pretty sure it can handle the HP/ Torque you are looking for.


https://www.e90post.com/forums/showthread.php?t=1599790

[nyt]

Yes, but it's not cheap.

There are clutches from Precision Raceworks (the propulsive dynamics G3 clutches). Once around the 700-800whp mark, you have to worry about snapping input shafts.

There are also some billet shafts available from Nizpro. It's like 3k+ to get these to the US. This still requires some machine work to get in the transmission, specifically to the E piston. With this you can fit an additional two frictions for the E clutch.

You also need some upgraded bushings, as the stock ones are rubbish, wear fast, and do not hold pressure well.

I'll put up a full write up for upgrading the 6hp21 at some point. Figure it's going to cost at least 5k just on parts to do it properly. If anyone has specific questions before then, lmk.

clutches, shafts, seals, bushings, fresh solenoids, zip kit, etc.

[nicky dj]

Insane nyt . With that being said is the DCT more beneficial and cost effective than upgrading the 6AT at 5k+?

[street 335i]

Originally Posted by ragingpanda

I would consider swapping to a 6 speed manual transmission to handle that kind of power or go to a different platform altogether.

Originally Posted by ragingpanda

I would consider swapping to a 6 speed manual transmission to handle that kind of power or go to a different platform altogether.

I was saw a diy for this on the forum but I figured there might be a cheaper option out there, just looking for options

[street 335i]

Originally Posted by nyt

Yes, but it's not cheap.

There are clutches from Precision Raceworks (the propulsive dynamics G3 clutches). Once around the 700-800whp mark, you have to worry about snapping input shafts.

There are also some billet shafts available from Nizpro. It's like 3k+ to get these to the US. This still requires some machine work to get in the transmission, specifically to the E piston. With this you can fit an additional two frictions for the E clutch.

You also need some upgraded bushings, as the stock ones are rubbish, wear fast, and do not hold pressure well.

I'll put up a full write up for upgrading the 6hp21 at some point. Figure it's going to cost at least 5k just on parts to do it properly. If anyone has specific questions before then, lmk.

clutches, shafts, seals, bushings, fresh solenoids, zip kit, etc.


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What are your thoughts on the propulsion dynamics zf 6hp21, has it even been released

[nyt]

Originally Posted by nicky dj

Insane nyt . With that being said is the DCT more beneficial and cost effective than upgrading the 6AT at 5k+?

Depends what you're after. If going DCT, you're also looking at 2k or so just for the clutches to hold that power.

In my case, I wanted an auto trans. It's nicer to the drivetrain and now the tcu is cracked so it can be tuned properly.

[street 335i]

Originally Posted by nicky dj

mw - is a DCT out of a IS is a straight swap for swap with the z6AT?

Thank you for all the suggestions I believe the fact is the best option

[nyt]

Originally Posted by street 335i

What are your thoughts on the propulsion dynamics zf 6hp21, has it even been released

There is no PD 6hp21 really. You can put in their bushings and clutches, but then you're still left with the input shafts being the weak point. PD was sold to PR, and they were looking at cryo treating shafts... which really won't do fuckall.

Nizpro put together some 6hp21s, I think VTT has one, but they do weird shit like use oem bushes. They're vaporware at this point anyway.

Best options currently for the 6at seem to be pd clutches and bushings and nizpro shafts.

Nizpro can't really be assed about selling the shafts they have, but if you bother them enough, you can get a set. It's still not plug and play from there, takes a bit of machining to get everything, but nothing crazy.

Unfortunately adapting a 6hp28 is a major pita, since those have heaps of support and it's easy to find parts or even built units.

[mweisdorfer]

Originally Posted by street 335i

I was saw a diy for this on the forum but I figured there might be a cheaper option out there, just looking for options

Why not retrofit an M3 DCT tranny & differential?

[street 335i]

Originally Posted by mweisdorfer

Why not retrofit an M3 DCT tranny & differential?

That's my plan when it comes around it will also greatly improve handling

[rev210]

I have a fully built Nizpro trans (by Nizpro) in my car.
As mentioned you can still get the input shafts etc. from them. I think between the DCT conversion with clutches and built Auto the dollars will be up there.

Cheaper to sell the car and buy another one with DCT
If cost is a factor. Thats probably the smart move money wise.

[nyt]

Originally Posted by rev210

I have a fully built Nizpro trans (by Nizpro) in my car.
As mentioned you can still get the input shafts etc. from them. I think between the DCT conversion with clutches and built Auto the dollars will be up there.

Cheaper to sell the car and buy another one with DCT
If cost is a factor. Thats probably the smart move money wise.

How's your nizpro trans doing? How much power you putting through it?

[rev210]

Originally Posted by nyt

How's your nizpro trans doing? How much power you putting through it?

Going great. XHP could do with a custom tune, thats now on the cards. The stage 3 xhp is ok but, I hear custom tunes are the way to go.
Havent had it on a dyno recently but, it ran 10.7@131mph full weight on road tyres.
So quick enough to break a standard trans.

[type-dRew]

Originally Posted by rev210

Going great. XHP could do with a custom tune, thats now on the cards. The stage 3 xhp is ok but, I hear custom tunes are the way to go.
Havent had it on a dyno recently but, it ran 10.7@131mph full weight on road tyres.
So quick enough to break a standard trans.

Have Rod at Sutphin Tuning cook you up something. He loves working with upgraded hardware.

[rev210]

Originally Posted by type-dRew

Have Rod at Sutphin Tuning cook you up something. He loves working with upgraded hardware.

Yes. Hes the guy people are pointing out. Heard good things.

[sneakyxshooter97]

Hey i have the 4F82 & 4F85 code in my 09 e90 335i. When i look up the 4F85 code it says to change my input shaft bearings.. can anyone tell me if this is a job that can be completed without removing the transmission? Or will it need to come out all together to replace the bearings?

Also anyone else have these codes and just swapped solenoids and that worked? I have a new solenoid set and all 5 of those special gaskets for the mechatronic/trans mating

Originally Posted by nyt

Yes, but it's not cheap.

There are clutches from Precision Raceworks (the propulsive dynamics G3 clutches). Once around the 700-800whp mark, you have to worry about snapping input shafts.

There are also some billet shafts available from Nizpro. It's like 3k+ to get these to the US. This still requires some machine work to get in the transmission, specifically to the E piston. With this you can fit an additional two frictions for the E clutch.

You also need some upgraded bushings, as the stock ones are rubbish, wear fast, and do not hold pressure well.

I'll put up a full write up for upgrading the 6hp21 at some point. Figure it's going to cost at least 5k just on parts to do it properly. If anyone has specific questions before then, lmk.

clutches, shafts, seals, bushings, fresh solenoids, zip kit, etc.

[iqraceworks]

Originally Posted by sneakyxshooter97

Hey i have the 4F82 & 4F85 code in my 09 e90 335i. When i look up the 4F85 code it says to change my input shaft bearings.. can anyone tell me if this is a job that can be completed without removing the transmission? Or will it need to come out all together to replace the bearings?

Also anyone else have these codes and just swapped solenoids and that worked? I have a new solenoid set and all 5 of those special gaskets for the mechatronic/trans mating

Have you ever done a full service on your transmission? New fluid, filter pan, sleeve seals, D seal, and shift solenoids? I would definitely try that before jerking the entire transmission out of the car and trying to replace just the bushings.