[Stanio]

Wanted to see if anyone has done a transmission swap with a ZF8HP70 on their F30 335.

As tuners begin go push the cars further and further into the 550+ wtq range. Transmission issues are inevitable.

I am aware that couple of people are pushing close to those toque numbers (maybe surpass them) and have no issues (yet) but they also don't beat their cars on a track events, where cars are running more than 20+ min non-stop. The tranny would not fare well with the heat and the stress on a consistent basis...it may be good for single pulls but a constant hard driving on a track...it would not end well.

Before we start breaking parts on the HP45 ...I was wondering if anyone has come up with upgraded hardware for those transmissions and if anyone has swapped the transmission from the F30 Activehybrid 3 or the F30 335d, which is ZF8HP70(holds around 35% more torque than the hp45), onto the F30 335 ?

I know that couple of companies are coming out with a flash tune for the transmission later on this year...but so far I am unaware if anyone has any hardware upgrades. This seems strange because the ZF 8HP45 is such a common transmission not only in BMW models....

I would appreciate your input and info.

Thanks

[Dfahmy]

I'm also looking into this, as I don't think the transmission will fair well after a turbo upgrade and an aggressive tune

[LiNDi]

Subscribed!

[Lancelot]

Originally Posted by Stanio

Wanted to see if anyone has done a transmission swap with a ZF8HP70 on their F30 335.

As tuners begin go push the cars further and further into the 550+ wtq range. Transmission issues are inevitable.

I am aware that couple of people are pushing close to those toque numbers (maybe surpass them) and have no issues (yet) but they also don't beat their cars on a track events, where cars are running more than 20+ min non-stop. The tranny would not fare well with the heat and the stress on a consistent basis...it may be good for single pulls but a constant hard driving on a track...it would not end well.

Before we start breaking parts on the HP45 ...I was wondering if anyone has come up with upgraded hardware for those transmissions and if anyone has swapped the transmission from the F30 Activehybrid 3 or the F30 335d, which is ZF8HP70(holds around 35% more torque than the hp45), onto the F30 335 ?

I know that couple of companies are coming out with a flash tune for the transmission later on this year...but so far I am unaware if anyone has any hardware upgrades. This seems strange because the ZF 8HP45 is such a common transmission not only in BMW models....

I would appreciate your input and info.

Thanks

AH3 is 8P70H and is different, it contains the electric motor instead of the usual torque converter, so that wouldn't work.

[Polo08816]

Originally Posted by Stanio

Wanted to see if anyone has done a transmission swap with a ZF8HP70 on their F30 335.

As tuners begin go push the cars further and further into the 550+ wtq range. Transmission issues are inevitable.

I am aware that couple of people are pushing close to those toque numbers (maybe surpass them) and have no issues (yet) but they also don't beat their cars on a track events, where cars are running more than 20+ min non-stop. The tranny would not fare well with the heat and the stress on a consistent basis...it may be good for single pulls but a constant hard driving on a track...it would not end well.

Before we start breaking parts on the HP45 ...I was wondering if anyone has come up with upgraded hardware for those transmissions and if anyone has swapped the transmission from the F30 Activehybrid 3 or the F30 335d, which is ZF8HP70(holds around 35% more torque than the hp45), onto the F30 335 ?

I know that couple of companies are coming out with a flash tune for the transmission later on this year...but so far I am unaware if anyone has any hardware upgrades. This seems strange because the ZF 8HP45 is such a common transmission not only in BMW models....

I would appreciate your input and info.

Thanks

I don't believe anyone has yet.

But if your application is track use to include 20+ minute sessions and you want maximum reliablity, you're going down the wrong path. A Frankenstein 335i with over 550+ wtq is not likely to be more reliable than a F80/82 M3/M4 ZCP for track use where heat is a concern.

Cost wise, it doesn't make sense either. A rebuilt ZF 8HP70 is anywhere from $7000-10,000. You'll need custom tuning, fabrication work, and support to get this up and running. I think you're looking at spending $15,000 just to get this working.

Now you factor in the time cost and opportunity cost of spending time at a track weekend fixing/diagnosing issues with this Frankenstein build - you have to be comfortable that there's a good chance you're essentially forfeiting the entire cost/entry fee of a track weekend because this setup is not going to be reliable.

Also, if you ever think about reselling this car - be prepared to for the car to be worth far less than the sum of its parts. No one in their right mind would ever buy a patchwork piece of shit.

The bottom line is that it's not worth it. If your use case is tracking it at HPDEs, you're much better off spending your money up front on a M3/M4.

[Stanio]

Originally Posted by Polo08816

I don't believe anyone has yet.

But if your application is track use to include 20+ minute sessions and you want maximum reliablity, you're going down the wrong path. A Frankenstein 335i with over 550+ wtq is not likely to be more reliable than a F80/82 M3/M4 ZCP for track use where heat is a concern.

Cost wise, it doesn't make sense either. A rebuilt ZF 8HP70 is anywhere from $7000-10,000. You'll need custom tuning, fabrication work, and support to get this up and running. I think you're looking at spending $15,000 just to get this working.

Now you factor in the time cost and opportunity cost of spending time at a track weekend fixing/diagnosing issues with this Frankenstein build - you have to be comfortable that there's a good chance you're essentially forfeiting the entire cost/entry fee of a track weekend because this setup is not going to be reliable.

Also, if you ever think about reselling this car - be prepared to for the car to be worth far less than the sum of its parts. No one in their right mind would ever buy a patchwork piece of shit.

The bottom line is that it's not worth it. If your use case is tracking it at HPDEs, you're much better off spending your money up front on a M3/M4.

Thanks for the input.

I wanted to mainly figure out if anyone has ever done that or a "simple" clutch upgrade solution was out there. I am aware of the cost for a transmission swap..and unless you had a spare one lying around...it would not make sense.

I am contemplating a turbo upgrade maybe in couple of months time but I just don't think the tranny will fair well past the numbers I quoted.

[bradsm87]

Originally Posted by Polo08816

But if your application is track use to include 20+ minute sessions and you want maximum reliablity, you're going down the wrong path. A Frankenstein 335i with over 550+ wtq is not likely to be more reliable than a F80/82 M3/M4 ZCP for track use where heat is a concern.

Cost wise, it doesn't make sense either. A rebuilt ZF 8HP70 is anywhere from $7000-10,000. You'll need custom tuning, fabrication work, and support to get this up and running. I think you're looking at spending $15,000 just to get this working.

Now you factor in the time cost and opportunity cost of spending time at a track weekend fixing/diagnosing issues with this Frankenstein build - you have to be comfortable that there's a good chance you're essentially forfeiting the entire cost/entry fee of a track weekend because this setup is not going to be reliable.

Also, if you ever think about reselling this car - be prepared to for the car to be worth far less than the sum of its parts. No one in their right mind would ever buy a patchwork piece of shit.

The bottom line is that it's not worth it. If your use case is tracking it at HPDEs, you're much better off spending your money up front on a M3/M4.

I disagree on most points. It's hardly a "Frankenstein" build. You just get an 8HP70 with the parts used on the Alpina B3 and use the Alpina B3 TCU calibration. The DME and everything else in the car will already work perfectly with it and the transmission will work just the same as an Alpina B3 which is N55 with 8HP70.

[Polo08816]

Originally Posted by bradsm87

I disagree on most points. It's hardly a "Frankenstein" build. You just get an 8HP70 with the parts used on the Alpina B3 and use the Alpina B3 TCU calibration. The DME and everything else in the car will already work perfectly with it and the transmission will work just the same as an Alpina B3 which is N55 with 8HP70.

It's most definitely a Frankenstein build for you - as the individual end user - because you're going to end up needing to do all the leg work. Alpina does not sell the B3 S model in the United States. You're making it sound easy, but it's not. If it were easy, in the United States would have already done it.

Even then, I'm almost positive that both the time and material cost will exceed the purchase price of an Alpina B3 S which is approximately 61,000 Euros - or low 70,000 USD.

It'll end up costing the same if not more than buying a brand new M3 ZCP, except if something goes wrong, you're on your own. You won't be able to drop it off at a dealer and let them figure out what's wrong with an M3 ZCP under factory warranty.

[M-terkait]

Originally Posted by bradsm87

I disagree on most points. It's hardly a "Frankenstein" build. You just get an 8HP70 with the parts used on the Alpina B3 and use the Alpina B3 TCU calibration. The DME and everything else in the car will already work perfectly with it and the transmission will work just the same as an Alpina B3 which is N55 with 8HP70.

good point, plus I can add 335d runs 8HP70. so fitting it under there should be possible adding that your point of N55 is already coupled with 8HP70 in B3, I think it could also be a direct swap.

[Polo08816]

Originally Posted by M-terkait

good point, plus I can add 335d runs 8HP70. so fitting it under there should be possible adding that your point of N55 is already coupled with 8HP70 in B3, I think it could also be a direct swap.

The bottom line is that while you "could", you shouldn't.

At the end of the day, the cost of doing so and supporting such a configuration is more costly than just buying a brand new M3/M4 ZCP.

[Dfahmy]

Originally Posted by Polo08816

The bottom line is that while you "could", you shouldn't.

At the end of the day, the cost of doing so and supporting such a configuration is more costly than just buying a brand new M3/M4 ZCP.

You can find these transmissions used for less than 2k used, so depending on if it bolts right up or how much modification it requires to fit I doubt it would be anywhere close to that price

[M-terkait]

Originally Posted by Polo08816

The bottom line is that while you "could", you shouldn't.

At the end of the day, the cost of doing so and supporting such a configuration is more costly than just buying a brand new M3/M4 ZCP.

M3 cost 150% more than 335i mostly in everywhere except USA.

Maybe if you don't have a heavily modified N55 you might be better with S55.

[Polo08816]

Originally Posted by Dfahmy

You can find these transmissions used for less than 2k used, so depending on if it bolts right up or how much modification it requires to fit I doubt it would be anywhere close to that price

If it were technically simple and inexpensive to do, then I'm sure someone would have done it already. I'm willing to bet that it's not.

Also, the original poster wants to use this setup at the track when you can be pushing the car to its engineering limits for 20+ minutes. That's vastly different than straight line acceleration for 20 seconds.

I'm 99.9% sure that this Frankenstein setup will be less reliable/dependable than a stock M3 ZCP in that particular use case.

Originally Posted by M-terkait

M3 cost 150% more than 335i mostly in everywhere except USA.

Maybe if you don't have a heavily modified N55 you might be better with S55.

Good thing the original poster lives in the United States just like I do.

[bradsm87]

Originally Posted by Polo08816

Also, the original poster wants to use this setup at the track when you can be pushing the car to its engineering limits for 20+ minutes. That's vastly different than straight line acceleration for 20 seconds.

All the more reason to upgrade to the higher torque rated transmission.

So it's OK to run 600nm through a transmission that's rated for 450nm because it came with the car but it's not OK to run 600nm through a transmission that's rated for 700nm because it's a swap from another same-chassis-code car?

You don't need the whole transmission from the Alpina. A 335d or 550i one will probably do (cheap used), subject to further research with possible bellhousing and/or torque converter swap then flash the Alpina B3 calibration to the TCU.

[insanecoder]

I believe I looked into this a while back and the 8HP70 is a larger unit than the 45/50
you'd have to carve some more real-estate to fit this longer unit in
good luck

[Stanio]

Originally Posted by insanecoder

I believe I looked into this a while back and the 8HP70 is a larger unit than the 45/50
you'd have to carve some more real-estate to fit this longer unit in
good luck

I think you are right.

So the only other way is for a company to come up with an upgraded clutch for the current tranny....damn !

[Jpup]

The 8HP70 can take a beating too. I came from having a Challenger Scat Pack where this was the automatic offered. People would push 600whp and the transmission would hold up. Wasn't really til about 650+ did issues start to arise.

[terryd5150]

Originally Posted by Jpup

The 8HP70 can take a beating too. I came from having a Challenger Scat Pack where this was the automatic offered. People would push 600whp and the transmission would hold up. Wasn't really til about 650+ did issues start to arise.

I'm strongly considering a Scat Pack Challenger 392, although I'd go 6MT.

Are people actually getting 600 whp without supercharging & piston/rod replacement?

[Polo08816]

Originally Posted by bradsm87

All the more reason to upgrade to the higher torque rated transmission.

So it's OK to run 600nm through a transmission that's rated for 450nm because it came with the car but it's not OK to run 600nm through a transmission that's rated for 700nm because it's a swap from another same-chassis-code car?

You don't need the whole transmission from the Alpina. A 335d or 550i one will probably do (cheap used), subject to further research with possible bellhousing and/or torque converter swap then flash the Alpina B3 calibration to the TCU.

When did I ever say the text in bold? My position has always been you should not make substantial powertrain modifications if your use case is tracking the car.

Simply looking at the torque rating of a transmission doesn't take everything - to include dealing with heat - into account. Over prolonged use, heat is what will cause a transmission to fail. Every single transmission has different heat properties as evidenced by the different part numbers between heat exchanges of a 8HP45 and 8HP50 transmission. If you were just drag racing for less than 30 seconds, heat is less of an issue. As long as the transmission can handle the torque you should be okay.

But the OP is asking specifically for the use case of tracking the car. In which case, it's far less expensive to buy an M3 ZCP and track it with a stock powertrain. If anything fails, it will likely be covered by warranty. Certainly not the case if you bring your car into a dealership with a transmission that was never designed for that particular car.

Originally Posted by insanecoder

I believe I looked into this a while back and the 8HP70 is a larger unit than the 45/50
you'd have to carve some more real-estate to fit this longer unit in
good luck

In which case, it would seem this modification requires some fabrication and not nearly as easy as a bolt in application. If no one's ever done it before, the OP can be sure he'll need to pony up the time and effort to get it working.

[Jpup]

Originally Posted by terryd5150

I'm strongly considering a Scat Pack Challenger 392, although I'd go 6MT.

Are people actually getting 600 whp without supercharging & piston/rod replacement?

I had the 6MT, get a barton and its the best thing ever. 600whp takes a supercharger, 500whp NA is a good goal to shoot for.

[bradsm87]

As stated a few times already, 8HP70 is already present in F3x 335d, Alpina B3 and AH3. BMW do not use different transmission tunnels for different models. They use the same chassis for all variants and you can fit the biggest transmission into any variant. Just because the 8HP70 is bigger than the 8HP45 doesn't mean it won't fit. It fits into the above models just fine and the chassis/body/tunnel is the same as the other models.

[Lancelot]

For the sake of clarity, the AH3 uses a 8P70H not a 8HP70, different beasts;
http://www.realoem.com/bmw/enUS/show...diagId=24_1341

335dX is 8hp70z AWD
http://www.realoem.com/bmw/enUS/show...diagId=24_1231
Being awd i'm not sure if it's swappable or not.

Perhaps 5 series (550i) are compatible donors? They have an 8hp70z too.