BMW M135i vs BMW 1M: Performance Stats

[BMW86]

I'm a big fan of the DCT but I think it's 2 biggest downsides are:
- it's not easy to launch, therefore not the best for drag racing
- diff is welded so aftermarket LSD's are 4k +
Everywhere else, the DCT is unbelievable. If these things aren't a concern than the DCT is perfect.

I personally prefer the 8spd because imho, it felt 90% as quick as the DCT which is amazing. I assume the 8spd is bolted as opposed to welded so LSD is only a 2k investment and it shouldn't be any harder to launch than the 6spd steptronics. Plus you've got an extra 2 gears over the N54 step and N55 DCT so fuel economy gets even better on the highway.

Both transmissions are amazing though.

[pavo335]

Originally Posted by BMW86

I'm a big fan of the DCT but I think it's 2 biggest downsides are:
- it's not easy to launch, therefore not the best for drag racing
- diff is welded so aftermarket LSD's are 4k +
Everywhere else, the DCT is unbelievable. If these things aren't a concern than the DCT is perfect.

I personally prefer the 8spd because imho, it felt 90% as quick as the DCT which is amazing. I assume the 8spd is bolted as opposed to welded so LSD is only a 2k investment and it shouldn't be any harder to launch than the 6spd steptronics. Plus you've got an extra 2 gears over the N54 step and N55 DCT so fuel economy gets even better on the highway.

Both transmissions are amazing though.

I thought all since about 09 were welded? plus DCT is a 7 cog

[BMW86]

Originally Posted by pavo335

I thought all since about 09 were welded? plus DCT is a 7 cog

Never said DCT wasn't 7 spd

Btw, I'm 09 N54 bolted. My wavetrac was 2k installed incl diff oil. Don't think I'd ever cough up 4k+ for an LSD.

[DR-JEKL]

Originally Posted by BMW86

Never said DCT wasn't 7 spd

Btw, I'm 09 N54 bolted. My wavetrac was 2k installed incl diff oil. Don't think I'd ever cough up 4k+ for an LSD.

I also thought all later models were welded as apparentley this method saves bmw $ in manufacturing costs.

May I ask who installed your diff (I realise you're in qld am im in nsw) and what diff oil do you run? I'm getting ready to organise to have my wavetrac installed, but am thinking i might at well get the subframe bushes, coilovers toe arms sways end links installed whilst she is all apart

[BMW86]

Originally Posted by DR-JEKL

I also thought all later models were welded as apparentley this method saves bmw $ in manufacturing costs.

May I ask who installed your diff (I realise you're in qld am im in nsw) and what diff oil do you run? I'm getting ready to organise to have my wavetrac installed, but am thinking i might at well get the subframe bushes, coilovers toe arms sways end links installed whilst she is all apart

I'm not sure on the reasoning. Yours will be welded since yours is a manual. Accelerate Automotive in Coopers Plains did mine. They've done a few now and I had no issues. I'm using redline 75w140Ns, I think. Dropped the diff oil at 3k because I'm OCD. You have the right idea about installing the other components at the same time as dropping the rear subframe is very labour intensive.

[DR-JEKL]

Originally Posted by BMW86

I'm not sure on the reasoning. Yours will be welded since yours is a manual. Accelerate Automotive in Coopers Plains did mine. They've done a few now and I had no issues. I'm using redline 75w140Ns, I think. Dropped the diff oil at 3k because I'm OCD. You have the right idea about installing the other components at the same time as dropping the rear subframe is very labour intensive.

Mine is bolted by memory all pre mid 07 were all bolted

I have heard its wise to change diff oil as often as your crankcase if you drive your car hard.

And another excuse to buy all the supporting parts also to do with the diff

[BMW86]

Originally Posted by DR-JEKL

Mine is bolted by memory all pre mid 07 were all bolted

I have heard its wise to change diff oil as often as your crankcase if you drive your car hard.

And another excuse to buy all the supporting parts also to do with the diff

I didn't realise yours is an 07, there's a good chance yours is bolted as I recall they switched to welded around that time.

I was told the diff oil didn't need changing but I always change any and all fluids well in advance. I'll probably change the diff oil again at 30k for peace of mind. Already have stocked up on the oil anyway

If you go with Wavetrac the Redline 75w140ns is the only recommended oil. It is essential that you use the Non-slip version otherwise you will void your warranty.

[BMJ]

Originally Posted by Dackelone

Can you guys just imagine what a M135i would turn lap wise with ALL the 1M suspension bits and an engine flash tune!

what about a 1M with a tune!

[pavo335]

Originally Posted by BMW86

Never said DCT wasn't 7 spd

Btw, I'm 09 N54 bolted. My wavetrac was 2k installed incl diff oil. Don't think I'd ever cough up 4k+ for an LSD.

ok, just the way you worded 'Plus you've got an extra 2 gears over the N54 step and N55 DCT' sounded like you thought it was a 6 speed'

[pavo335]

Originally Posted by BMJ

what about a 1M with a tune!

well they need it to keep up with all the other n54/5's

[BMW86]

Originally Posted by BMJ

what about a 1M with a tune!

It's all the 1M really needs.

Originally Posted by pavo335

ok, just the way you worded 'Plus you've got an extra 2 gears over the N54 step and N55 DCT' sounded like you thought it was a 6 speed'

Sorry pav, I can see where you're coming from now.