If you have an LSD,

[Traf]

Did a M3 diff conversion on my 135i MT, frankly it's nice, even if the M3 diff is not the best.
There is more diff upgrade options in the M3 housing than the 135i ones anyway.

[lowbudgethero]

Originally Posted by asiflicious

If you've put in an LSD in your automatic 135i, did you buy just the differential or the entire pumpkin? I believe all auto (steptronic-NOT DCT) 135i's had bolted diffs so wouldn't you just need the diff itself and just swap it into your oem pumpkin?[IMG][/IMG]

Only certain years had bolted diffs from the 335i, the draw back is you would have to have 3.46 gearing unless you change the gears too. I bought an entire pumpkin, because it was a lot cheaper and faster than getting my diff sent out for work.

[asiflicious]

Originally Posted by lowbudgethero

Only certain years had bolted diffs from the 335i, the draw back is you would have to have 3.46 gearing unless you change the gears too. I bought an entire pumpkin, because it was a lot cheaper and faster than getting my diff sent out for work.

So this information is not accurate?

[lowbudgethero]

Originally Posted by asiflicious

So this information is not accurate?

that info is accurate

for manuals we needed the large diff from the 335i auto for an "easy" swap

I forgot that the 335i manuals had bolted diffs too, it's just more common to find the 335i auto rear end.

[asiflicious]

Originally Posted by lowbudgethero

that info is accurate, the 135i auto had the small diff though

for manuals we needed the large diff from the 335i auto for an "easy" swap

My 135i is an auto so I have the small bolted diff. Does this mean that I wouldn't need the whole pumpkin? Would the labor cost be about the same swapping out the entire pumpkin versus swapping out the diffs within the pumpkin? Or would one be quicker and cheaper?

[lowbudgethero]

Originally Posted by asiflicious

My 135i is an auto so I have the small bolted diff. Does this mean that I wouldn't need the whole pumpkin? Would the labor cost be about the same swapping out the entire pumpkin versus swapping out the diffs within the pumpkin? Or would one be quicker and cheaper?

You have to take the whole pumpkin out to swap the diff anyway

I'd rather get the entire pumpkin from a company if it were me

[iminhell1]

If you're this on the fence about which to buy, just wait for a sale. It's not something you NEED. I'm sure someone will have a sale beginning of Spring. That should save you $100+.

I bought mine on a black friday sale and got $200 off a bare unit. I got the diff and solid bushings to my door for $965.34.
Bought new seals from FCP for $26.74 and 12 cv shaft bolts (just in case) for $26.28.
Borrowed a driveshaft wrench for ~$35.
New diff fluid, about $40.

So my grand total was about $1,100 with bushings.

[asiflicious]

Originally Posted by lowbudgethero

You have to take the whole pumpkin out to swap the diff anyway

I'd rather get the entire pumpkin from a company if it were me

Is a pumpkin swap relatively easy enough to do that anyone with the tools and mechanical experience can do it or would you recommend taking it to a shop?

[asiflicious]

Originally Posted by iminhell1

If you're this on the fence about which to buy, just wait for a sale. It's not something you NEED. I'm sure someone will have a sale beginning of Spring. That should save you $100+.

I bought mine on a black friday sale and got $200 off a bare unit. I got the diff and solid bushings to my door for $965.34.
Bought new seals from FCP for $26.74 and 12 cv shaft bolts (just in case) for $26.28.
Borrowed a driveshaft wrench for ~$35.
New diff fluid, about $40.

So my grand total was about $1,100 with bushings.

And that was just for the diff?

[lowbudgethero]

Originally Posted by asiflicious

Is a pumpkin swap relatively easy enough to do that anyone with the tools and mechanical experience can do it or would you recommend taking it to a shop?

It's not terrible, I have mechanical experience, but it's not part of my profession. I also didn't want to spend too long without the car at the time.

I paid ~400 for labor + fluid at a bmw indie repair shop, I think it's ~5-6 hrs labor on the books.

[iminhell1]

Originally Posted by asiflicious

And that was just for the diff?

Yes. That is just parts.
But you can take off about $200 if you remove the bolts and bushings. I would recommend getting at least a couple bolts just in case though. I did booger the head on one and it wasn't reusable.


I actually have not installed the bushings yet. My plan here is to buy another rear subframe and do a complete swap with new arms, bushings and all that jazz. I'm in no hurry to do this though.

[asiflicious]

Originally Posted by iminhell1

Yes. That is just parts.
But you can take off about $200 if you remove the bolts and bushings. I would recommend getting at least a couple bolts just in case though. I did booger the head on one and it wasn't reusable.


I actually have not installed the bushings yet. My plan here is to buy another rear subframe and do a complete swap with new arms, bushings and all that jazz. I'm in no hurry to do this though.

What are your thoughts now that you've had more time to play with it?

[iminhell1]

BUY ONE.
Fun time in the car is so much more controllable. You can literally drive down the road sideways and in control. It's just a strange feeling the first few times, does not feel real with how easy it is.

I did a auto-x couple weekends ago and I was too scared to turn DTC full off. I really should have to see how the car did. Full on and in DTC you'll notice no difference. It's once it's all off that you find how fun the car can be.

I think I'm going to code the ediff back into the car though. The more I learn about how a Torsen style works, it's a benefit to have it.

[asiflicious]

Originally Posted by iminhell1

BUY ONE.
Fun time in the car is so much more controllable. You can literally drive down the road sideways and in control. It's just a strange feeling the first few times, does not feel real with how easy it is.

I did a auto-x couple weekends ago and I was too scared to turn DTC full off. I really should have to see how the car did. Full on and in DTC you'll notice no difference. It's once it's all off that you find how fun the car can be.

I think I'm going to code the ediff back into the car though. The more I learn about how a Torsen style works, it's a benefit to have it.

Nice! Does it make a difference in daily driving as well or just when at 10/10?

[iminhell1]

Maybe a little DDing. But just driving normal you won't notice a thing. It's when you push it you really notice.

[asiflicious]

Originally Posted by iminhell1

Maybe a little DDing. But just driving normal you won't notice a thing. It's when you push it you really notice.

I was honestly partly hoping you'd say it wasn't worth it. Now I reallyyyy want one

[asiflicious]

Guys, would I be crazy to get an LSD and subframe bushings instead of anything else??

[iminhell1]

Originally Posted by asiflicious

Guys, would I be crazy to get an LSD and subframe bushings instead of anything else??

No.


Last night I was doing some straightline testing, really haven't done much yet.
Traction off, 1'st gear limited to 100 load (no boost) 2nd is 130 and 3rd is 160, on my 215 snow tires and 18*F outside; I could launch in 1st and stick. No tire spin in any gear even on sorta sandy roads. I'm on the OTS E60 tune which is about 18psi and near that 400whp mark.
I'm finding that boost by gear combined with the LSD is pure magic. It's like the more I play around the more capable I find this car is at everything.

[asiflicious]

Originally Posted by iminhell1

No.


Last night I was doing some straightline testing, really haven't done much yet.
Traction off, 1'st gear limited to 100 load (no boost) 2nd is 130 and 3rd is 160, on my 215 snow tires and 18*F outside; I could launch in 1st and stick. No tire spin in any gear even on sorta sandy roads. I'm on the OTS E60 tune which is about 18psi and near that 400whp mark.
I'm finding that boost by gear combined with the LSD is pure magic. It's like the more I play around the more capable I find this car is at everything.

How does it effect launching from a standstill? Does help get off the line better?

[iminhell1]

Originally Posted by asiflicious

How does it effect launching from a standstill? Does help get off the line better?

The boost or load by gear?
Works amazingly well. takes a few tries to find the correct setting for the tire/condition. But once you do it's repeatable results. I really like this option!


Saturday I got some drag racing time in at the track. Granted my summer tires are absolute shit, 1/32 left ... still on the Firehawks (love those things), track prep was fair but conditions where not sunny and not really warm enough to make track prep work. I always forget that the tires NEED heat in them to work. Short clean off burnouts wont do. You have to spin until you see a little smoke.
Once I get them warm I could hook, managed fairly consistent 1.8x's and a high 1.7x.
With clean up burnout I was doing 2.1's. Just skating the whole way.


So right now, I'm doing the same 60's I did without the LSD. Tuesday new tires get here and next Wednesday I'll get some more track time in.
I need to try a harder boost launch ans see if I can get into that 1.6x range consistently. If I can do that then I'll say the diff is very good money spent for all situations.
Right now my opinion is that turning situations it's a must. All straightline it's a crapshoot (LSD does not make up for poor tire or tire condition).

[Wegz]

I'm liking mine so far. Went with the 3.46 ratio on my 6mt car. My only mods are Dinan S2 tune and BMW PE.

[Dylanize]

Is there anyway to check if you have an LSD? I bought my car used but it had some modifications done by the previous owner.

I know some people mentioned some weirdness with an LSD and the traction control, and my car has the most intrusive traction control I've ever experienced, completely ruins the driving experience most of the time.