e36 vs e30 transmission

[Rev Engineer]

Can anyone point to me a thread where this has been discussed? I'm still undecided on which route to go as I have both transmissions in my garage. Here's some thoughts I'm tossing around about each:

I thought the e30 getrag 260 was much lighter but I weighed them last night and found that the Getrag 260 is only 6 pounds lighter than the ZF-310. So, weight concerns don't push me in any certain direction.

Someone commented that the s50/s52 can wear out a Getrag 260 rather quickly.

I personally like the shift feel of the ZF over the Getrag.

The ZF transmission is worth a lot more so I could save some money by using the Getrag and selling the ZF.

The Getrag requires modification or fabrication of the transmission mount bracket. This part scares me a little and is making me think that the ZF might be a lot simpler to install.

It's pretty well confirmed that the ZF + e30 m3 driveshaft works (and I have a e30 driveshaft). If I use the Getrag 260, I'm not sure which driveshaft will work.

All in all, it's a bit of a toss up. I will be using a stock e30 lightened flywheel with a stock e30 clutch/pressure plate. I understand that this setup will work with either transmission as long as I pay attention to the clutch slave and throwout bearing distances.


Am I missing anything that might sway my decesion!? I havn't looked into gearing yet, but I believe they are similar and the 3.25 diff works well with either. Is that a true statement?

[FredK]

The 260 and the ZF 310 have different gearing.

Getrag 260
1st- 3.83
2nd- 2.20
3rd- 1.40
4th- 1.00
5th- 0.81

ZF 310/320
1st 4.21
2nd 2.49
3rd 1.66
4th 1.24
5th 1.00

So if you use a 3.25 with the Getrag 260, you will have lower revs than on the ZF, because the ZF has a 1:1 5th gear, and the Getrag has a overdriven .81 5th gear. You'd be better off with a 3.73 with the Getrag and a 3.25 with the ZF (or Getrag 250 as found in the 92-95 E36 325i).

You can check the speed in each gear with a gear calculator, like the one found on diffsonline.com.

[sweetride01]

What car is the ZF310 from?

[FredK]

95 M3
early S52 engine M3
1991-92 525i

Later M3s had the ZF 320. Functionally and dimension-wise I believe it was identical.

[sweetride01]

Is there a tranny you can put in that will prevent the infamous "money shift" problem that the e36 M3 had?

[Rev Engineer]

Is there a tranny you can put in that will prevent the infamous "money shift" problem that the e36 M3 had?

I forgot that one. Certainly a disadvantage to the ZF. I believe this problem is specific to the ZF since it's synchros actually work well enough to allow you to select the wrong lower gear when you're going fast. Maybe the same reason why I think the ZF shifts smoother than the Getrag 260.

Thanks for the gearing info, Fred!

My ZF came from a 95 M3.

[matt]

If you reinforce your tranny mounts properly and pay a little attention when you shift you won't have a moneyshift problem. That issue is caused by tranny mounts flopping around + improper shifting technique, not a design problem with the tranny.

[morontron]

If you use the ZF, can I buy your Getrag and driveshaft? :]

[1991 318is]

Gear ratio calculator.

I have nice one that I wrote with another racer back in the 90's. It's for Hewland and Weissman transmissions but is easy to use with regular transmissions. It also prints Hewland type charts. PM me if you would like a copy. Price is right ($0). Windows only.

[E304life]

Any one know if there was ever a 260 with direct 1:1 5th gear.

The reason I ask i cus I have a Eta 260 with a 4:10 diff with a i engine,
at 80mph I am at about 4,000 rpm.
My tire size is 205/60R14

This could be a factor when deciding what way to go on a trans.

[erik325i]

Someone commented that the s50/s52 can wear out a Getrag 260 rather quickly.

Can someone confirm this? I know that the Getrag 260 is stronger than the e36 325 tranny, but how does it compare with the ZF?

I am also trying to decide which tranny to use with my s50...
I already have an e30 m3 driveshaft, and a 3.23 LSD, so I am leaning towards the ZF. Those suckers are expensive though. I'm half tempted to buy a 6-speed...

-Erik

[X2theZ3]

Can someone confirm this? I know that the Getrag 260 is stronger than the e36 325 tranny, but how does it compare with the ZF?

I am also trying to decide which tranny to use with my s50...
I already have an e30 m3 driveshaft, and a 3.23 LSD, so I am leaning towards the ZF. Those suckers are expensive though. I'm half tempted to buy a 6-speed...

-Erik

i'd say go for the zf. After having owned a 90 325i as my previous car, i like the feel of the zf better than the getrag260.

[gjuu]

Any one know if there was ever a 260 with direct 1:1 5th gear.

The reason I ask i cus I have a Eta 260 with a 4:10 diff with a i engine,
at 80mph I am at about 4,000 rpm.
My tire size is 205/60R14

This could be a factor when deciding what way to go on a trans.

Rev Calculator

136.59km/hr or approx 82mph
with a 0.81:1 fifth gear

[E304life]

^^^ nice link

[Kilomph]

So will any year ZF-320 bolt right up to an S50?

I can't decide between a 2.93, 3.15 and 3.23.

225/50-15

2.93 @ 80MPH = 3303 RPM
3.15 @ 80MPH = 3550 RPM
3.23 @ 80MPH = 3640 RPM

It's about a 2mph difference between 15/23 in top gear, which isn't that big of a deal. But I don't really like being that far past the 3500RPM mark at cruising speed, and I wouldn't mind the better MPG. How's the 2.93 in terms of acceleration?