Can a BMW 6 Speed Tranny Work On Our Ti's?

[inlacal]

Can it be done?

Can the european 6 speed (95/96 M3) fit in our cars?

Can any 6 speed BMW box fit in our cars?

I need more gears as I am approaching 4,000 rpm at cruising speed (75-80). I would like to have a cruising (freeway) gear.

Please advise.

Chris

[96cali]

I am pretty sure it will as the stock ti tranny will work with an M50/52 or S50/52 motor. Think you will need a custom drive shaft though, esp if you keep the small case diff.

[DustenT]

Yep, that'll work, no problem.

Also, the e46 330 6-speed with swap over as well. Check out this link: http://www.zionsvilleautosport.com/store/shop.mv?Screen=CTGY&Store_Code=6134&Category_Code=6SPC

[inlacal]

Yep, that'll work, no problem.

Also, the e46 330 6-speed with swap over as well. Check out this link: http://www.zionsvilleautosport.com/store/shop.mv?Screen=CTGY&Store_Code=6134&Category_Code=6SPC

Flying to Europe & picking up a 6 speed box at a junkyard and then exporting it back home would (almost) be cheaper than $4500.

Now my mind is made up. I'm going to do it.

Any thoughts on the kind of clutch to use?
Differential?

I have the 'sport package' so I assume my diff is already different over standard?

Chris

[mohaughn]

No. Only the 95 clubsport had a standard LSD. As yours is a 97 with ASC it probably doesn't have LSD. I think it may have been possible to still get it as an option on the 97.. You can easily look at the tag on the diff to determine what it is.

Also check out abloriginalparts.com, he has euro six speed transmissions for 2200 plus shipping crate/charges. You may have to wait on him to get one imported though. Seems like he gets a new shipment of euro motors/transmissions every other month or so.

[96cali]

Is that Alex Lipowiches site?

[bullmand]

This was discussed in the past on the Yahoo group and the consensus was that unless you also change the rear end gear ratio the 6th gear would put you too far below the powerband of the car to be usable. I don't know if that's actually the case or not, but it's something you should consider. Check the ratios on the cars that came with the 6 speed vs. our ratio. That should give you a place to start. Just because a part will fit doesn't mean it should fit.

[mohaughn]

Is that Alex Lipowiches site?

Yes. I believe that is his name.

[inlacal]

This was discussed in the past on the Yahoo group and the consensus was that unless you also change the rear end gear ratio the 6th gear would put you too far below the powerband of the car to be usable. I don't know if that's actually the case or not, but it's something you should consider. Check the ratios on the cars that came with the 6 speed vs. our ratio. That should give you a place to start. Just because a part will fit doesn't mean it should fit.

Was there a recommended rear end for this setup?

Chris

[bullmand]

I honestly don't remember. I can check the archives, but they're not user-friendly so it may take a few days.

Here are some comments I found:

It might be pretty good with a 4.44 diff from an auto and/or a DASC.

Changing the trans is a waste of time and in 6th at 65mph will put you way below the powerband. Run it at 3500 RPM's until it dies (est 150-200k miles) then put a new motor in it. This will be cheaper in the long run and you will have more power at your disposal along the way.

Unless your ti is producing significantly more power than stock
(supercharged, turbo, or otherwise) AND has a lower gear ratio final drive, I would not recommend it. Our fours need to turn plenty of rpm to be efficient, otherwise you use more throttle more of the time at rpm levels which produce little power and torque.

If your car IS producing significantly more power AND has a lower ratio final drive, I understand that it is a straight bolt-on to the M42. The 6-speed kit has its own driveshaft with a 6-bolt flange; our differentials are 4-bolt. I think Bimmerworld will modify your current driveshaft for length for around $150. I don't know of any other necessary modifications, nothing electrical that I know of. Of course, the transmission itself weighs 35 lbs more than the stock transmission, and pushing more weight down the road is always less efficient.

You could switch to a taller final drive ratio, but you'll run into
the same problems as with a 6-speed. The gear ratios won't be
well-matched to the engine, and acceleration will suffer.

There's a lot more in there, but that should give you an idea. It seems like there is the potential to spend a lot of money here for very little payoff. That's just my opinion. Hope all this helps.

[96cali]

I belive his Ti is DASC'd per his sig. Isn't there a site to calc the rpms per gear/diff? I wonder if going to a 3.15 or 3.23 diff would help w/o messing up the power availability?

[mohaughn]

I think you want to go the other way... Club race cars with 6 speeds use diffs in the 3.6x to 4.2x range depending on where they want their top speed and shift points.

[bullmand]

My grasp of this stuff is pretty loose, but I imagine you would need to figure out the relationship between the stock gearbox ratios and the stock rear end. From there you could take the 6 speed ratios and determine what the rear end ratio should be. Does that make sense? There's a strong possibility that it would be difficult to come up with a combination that would be comfortable for daily use. As mentioned above the DASC should help with that. I would probably call Zionsville and ask them what they think. Another piece of information you may want to have is the diff ratios for the 6 cylinder E36 models.

[96cali]

I think you want to go the other way... Club race cars with 6 speeds use diffs in the 3.6x to 4.2x range depending on where they want their top speed and shift points.

Again, his goal was to reduce RPMs at highway speed. He does not say anything about Club race cars, etc. What is the stock diff ratio on an e36 M3? 3.23? Automatics come with 4.10 diffs IIRC.

[Panzer_M]

6spd w. 3.73LS(E30 easy find) would be a good combo.

[inlacal]

Again, his goal was to reduce RPMs at highway speed. He does not say anything about Club race cars, etc. What is the stock diff ratio on an e36 M3? 3.23? Automatics come with 4.10 diffs IIRC.

95 M3's had a 3.15
With OBD II/3.2's they went to 3.23

Can anyone tell me what my stock diff is on my 97 Ti Sport Package?

Chris

[Mad-Machine]

I am not too worried about being below the torque curve on the highway... I do a LOT of highway miles in a relativly flat state, so if I can drop them a 1000rpms while cruising along at 70mph, I would be very happy.

Especially if 1st through 5th remained the same or a little tighter

[DustenT]

95 M3's had a 3.15
With OBD II/3.2's they went to 3.23

Can anyone tell me what my stock diff is on my 97 Ti Sport Package?

Chris

3.45:1 for a manual
4.44:1 for an automatic

[dave45056]

I did a little research and it looks like the 1-5 ratios of the 5 and 6 speed are essentially the same:
Gear....5 speed.....6 speed
1.........4.23:1.......4.35:1
2.........2:51:1.......2.50:1
3.........1.67:1.......1.66:1
4.........1.23:1.......1.23:1
5.........1.00:1.......1.00:1
6...........N/A.........0.85:1

Please correct me if I am wrong on these ratios.
But if they are correct, it looks like a 6 speed would offer me just what I am looking for when I phantom up-shift from 5th on the highway without changing the speed at which you currently shift gears.

[pdxmotorhead]

Sounds sweet to me, a .85 would drop your rpms nicely
quick table:

1:1 .85:1
1000 850
1500 1275
2000 1700
2500 2125
3000 2550
3500 2975
4000 3400
4500 3825
5000 4250
5500 4675
6000 5100

Not 100% due to the ratio in the final drive but it covers the idea....

Dave

[Mad-Machine]

I like.. sounds like a project to me!

[bmw318is1994]

hey here's some more info on the 6 speed into a 318! I asked about this on bimmerforums.com

http://forums.bimmerforums.com/forum/showthread.php?t=489885

[96cali]

Wow, nice thread you linked us to. Thanks!