Best all around gearing for s50?

[evoe46m3]

I wouldnt agree that the US s50 is a very peaky engine. Yes it makes most of its power from 4 to 6 but it still makes a substantial amount of torque at low engine speeds. I guess you are considering something to be non peaky like a 335i where the power band starts tapering off a lot farther from redline.

Anyways I used to have a 3.73 and I put in a my 2.79 for my move from Washington to Texas. I thought the car would be really slow but it its not that bad at all. first gear actually feels ideal with such tall gears. first is worthless with a 3.73 and super worthless with a 4.10. second is a bit too short too. I think that the best diff ratio with an s50 and a 260 would be something in between what I have and the 3.73. probably a 3.46 or a 3.25. You do get awesome mileage on the highway with the 2.79 though. I got around 32 33mpg averaging 75 mph from Seattle to Dallas.

[giantkeeper]

ZF with 3.15 is great!

[e30polak]

260 + 3.46

or

ZF with either 3.25, 3.23, 3.15 or 2.93

Or keep the 3.73 and get a 6 speed!


I've always hated the G260! :x

ZF feels sooooo much nicer IMO! Plus the 1:1 5th is awesome! :up:

[e30rapidic]

IMHO, optimal is a 6-speed with a 3.46.

this

[nrubenstein]

I wouldnt agree that the US s50 is a very peaky engine. Yes it makes most of its power from 4 to 6 but it still makes a substantial amount of torque at low engine speeds. I guess you are considering something to be non peaky like a 335i where the power band starts tapering off a lot farther from redline.

Anyways I used to have a 3.73 and I put in a my 2.79 for my move from Washington to Texas. I thought the car would be really slow but it its not that bad at all. first gear actually feels ideal with such tall gears. first is worthless with a 3.73 and super worthless with a 4.10. second is a bit too short too. I think that the best diff ratio with an s50 and a 260 would be something in between what I have and the 3.73. probably a 3.46 or a 3.25. You do get awesome mileage on the highway with the 2.79 though. I got around 32 33mpg averaging 75 mph from Seattle to Dallas.

My point of reference is my E46 M3. Compared to the S54, the S50US is quite peaky. All things are, of course, relative. It's a lot less peaky than an M20. Vanos is better than no vanos, but doppelvanos kicks the crap out of single vanos.

And for what it's worth, I've run both the 320 and the 260 with my 3.46 and I also fan a 4.10 with the 320. I really don't know why folks think that a short first is useless. Frankly, the 4.10 was the only gear that really made me happy with acceleration. It just really, really massively sucked on the highway.

[e30polak]

And for what it's worth, I've run both the 320 and the 260 with my 3.46 and I also fan a 4.10 with the 320. I really don't know why folks think that a short first is useless. Frankly, the 4.10 was the only gear that really made me happy with acceleration. It just really, really massively sucked on the highway.

If you've never driven a ZF with a 2.93, then you'll realize why 1st gear with a ZF and either a 3.73 or 4.10 is useless. With a 2.93 out back you can take second to almost 65 mph. While it may not feel as torquey, you make better use of your time in Vanos.

I liked the 2.93 + ZF better then my 3.25 or my 3.46. Too bad I only enjoyed it for a few weeks before I sold my swap car. i don't like all the shifting that the shorter gearing requires, and I love a longer, peak powerband.

[Wanganstyle]

S50 is OEM paired with 3.15 and ZF 1:15th gear. 1-5 are close spacing.
big brother S52 has same ZF transmission with a 3.23 final drive. same hp rating, just more torque from 200cc extra.


S50 with OEM e30 driveline G260+3.73 is very close to a S50 1995 stock e36m3 setup.


Math done with E30 OEM 195/60/14 tire size constant.

G260+3.73 oem final drive+ s50 with 7,000 rpm redline (chipped)
top speed per gear:

1: 34mph
2: 59
3: 92
4: 129
5: 160

G260+ 3.91

1: 32 mph
2: 56
3: 88
4: 124
5:162

G260+4.10

1: 31 mph
2: 54
3: 84
4: 118
5: 146


ZF sg320+ 3.15 final drive (BMW oem 95 s50 m3)+ 7k redline.

1: 36mph
2: 61
3: 92
4: 123
5: 153


comparing these 2, they are almost the same. Freeway gear 4 and 5 with the ZF setup will be tiny bit shorter and move better as the Zf is a FAUX close ratio box.

ZF sg320 e36m box+stock e30 tires+ 3.23 final drive (96-99 M3 BMW OEM spec)

1: 35mph
2: 60
3: 90
4: 120
5: 149


realistically, some one with a S50 swap keeping G260 and OEM 3.73 final drive will be = stock zf sg320 e36m setup for gears 1,2,3.

G260 gears 4/5 will freeway cruise (lower rpm)
ZF SG320 gears 4/5 wil accel slightly faster.

if you want to have better in-gear acceleration @ freeway speeds, the ZF SG320 will be a better choice. IF Fuel economy @ long distance commuting is more ideal for you, then the G260 tall 4/5 will save you fuel $$$.


e36M street cars like 3.38 and 3.46 gearing.
S50+ZF trans in E30 with similar OEM e30 size tire and 7,000 rpm chipped redline


ZF + 3.38:

1: 34mph
2: 57
3: 86
4: 115
5: 143


ZF+3.46

1: 33 mph
2: 56
3: 84
4: 112
5: 139




basically for freeway use:

ZF + 3.38 or 3.46

=

G260 + 3.91 or 4.10


for around town the G260 short 1-3 gears show up.

main complaints for G260 is gap between 3/4 - This gap is what helps fuel economy.

if owner likes fuel economy @ expense of accel between gears 3/4 (or is willing to have very short 1-3 gears for good 4/5 fwy accel), then G260+ 3.91/4.10 ideal.

IF the 1-3 gearing needs to be longer for in town fuel saving and freeway drives are less often (more for fun) then ZF 5mt is more ideal- its longer 1-3 and allows for long final drive to lower around town rpm's but short 4/5 lets the car accel quickly @ fwy speeds.



for reference; Street/hpde E36m's with ~7,000 rpm redline and ZF 5 speed box change to 3.38 or 3.46 final most often.
if you have 7500-8000 you can do a 3.64 or 3.73 pretty easily.

if you have a S54 you can push 3.91/4.10/4.27/4/45 depending on redline set.

S54+zf SG320+ 8388 rpm redline +3.38 final requires 2 shifts often to engage full top end power (6,000-8,400).
Most ideal S54 all round IMO would be a 6mt with 4.10; stock e46m is 7500 rpm and 3.62 final.

[giantkeeper]

The s50 ZF paired with the 3.15 in an E36 sucked. I always hated driving it unless at higher rpm's and speed.

This same gearing setup in the lighter E30 is an absolute blast. Pulls hard through every gear, and 5th gear at freeway speeds still has enough "oomph" to get the job done.

With that said, when I spec'd my build I was going to go after the 3.25. I ended up settling with the 3.15 and I'm ok with it now....lol

[Danny]

Still want a 3.46

[pandaboo911]

I vote ZF+ 2.79/2.93 for street only use. If you want to track it and street it, 3.15/3.46

[jrdeamicis]

I have run a 3.73 with my 6 speed and a 3.46 with my 6 speed. I am currently getting a 3.64 built.

[cbusrehab]

I have a zf with a 3.25 in my swap and it's great. I'm running tall tire set-up, 235/40/17, compared to stock. I sometimes need to drop into 4th for passing on the freeway, but 5th is fine most of the time.

It's not as fun as the 4.10 that was originally in there when I did the swap, but it's actually usuable on a daily basis now.

[nrubenstein]

If you've never driven a ZF with a 2.93, then you'll realize why 1st gear with a ZF and either a 3.73 or 4.10 is useless. With a 2.93 out back you can take second to almost 65 mph. While it may not feel as torquey, you make better use of your time in Vanos.

I liked the 2.93 + ZF better then my 3.25 or my 3.46. Too bad I only enjoyed it for a few weeks before I sold my swap car. i don't like all the shifting that the shorter gearing requires, and I love a longer, peak powerband.

I drove the E36 with the stock 3.15 for quite a while before the same motor ended up in the E30. The 3.15 sucked and was too slow. Being able to "stay in the long peak power band" is just another way of saying "it makes the car slow." It's true that a shift to 3rd generally makes 0-60 times suffer. However, overall acceleration dramatically improves. (This is reflected in 1/4 mile times.)

I'll be trying the 4.10 with the S50B32. It's probably going to be a little bit short on the highway, but it should pull nicely with an 8K rev limit.

[e30rapidic]

It's probably going to be a little bit short on the highway, but it should pull nicely with an 8K rev limit.

I hate my S50/zf/3.46 on a highway. Can't imagine what that 4.10 will be like. Bloody awful I suppose.

[samiam3356]

^^ perfect motor and gear just the wrong tranny