Gear ratio comparison...

[Jason89i]

Use the gearing calculator above. It is for the e36 trans.

zf
3.73 diff - 3rd gear, 6500rpms = 75mph
3.25 diff - 3rd gear, 6500rpms = 86mph

[mentaleeill]

i have ran the zf with the 3.73 which was way too short- redline 5th gear around 125mph. i then went to the 2.93 which was great just like the getrag with the 3.73, but i wanted a little more grunt from the bottom so i am now running the 3.25. it revs just like the getrag with a 4.10, decent on the highway and fun around town also.

[jrdeamicis]

First is useless with that ratio! 2nd-6th on the other hand... :up:

Thats the fun gear :)

I am buttoning up some details (Custom Coilovers using Short Koni Race DA) at the moment. I will get some videos very soon.

[e30polak]

Thats the fun gear :)

I am buttoning up some details (Custom Coilovers using Short Koni Race DA) at the moment. I will get some videos very soon.

It is fun, but useless in a race, and annoying for a DD!

I wish I could keep the duration of 2-5th with the 3.46 gears, but make 1st just little longer. The ZF+3.46 combo really is the must fun gearing I've driven in any car! :D

[WADE30]

What model/chassis is the 3.25 from? And can you just swap the whole case/diff over or do you have to swap the differential guts?

[jrdeamicis]

I wish I could keep the duration of 2-5th with the 3.46 gears, but make 1st just little longer. The ZF+3.46 combo really is the must fun gearing I've driven in any car! :D

Useless in a race? Please, No diff is useless :-D

You can do that. Please open your wallet, your asshole, and your mouth. Because you are going to take it in every hole :)

My car is not a DD but it will be Auto-x, HPDE, Track.

As soon as I find a 3.46 I am going to do that and hit a top speed of 170+

After that is shrick cams, 3.5" HFM, Euro Headers and then I'm done.

:pimp:

[jrdeamicis]

What model/chassis is the 3.25 from? And can you just swap the whole case/diff over or do you have to swap the differential guts?

I think its the Mcoupe / roadster chassis.

[Uber E30]

I think 3.15 is from the z3 and 3.25 is from an e28 535

[e30polak]

Useless in a race? Please, No diff is useless :-D

You can do that. Please open your wallet, your asshole, and your mouth. Because you are going to take it in every hole :)

My car is not a DD but it will be Auto-x, HPDE, Track.

As soon as I find a 3.46 I am going to do that and hit a top speed of 170+

After that is shrick cams, 3.5" HFM, Euro Headers and then I'm done.

:pimp:

Never said the diff was useless, just 1st gear. I had 4.10s when I started the swap and my friend has 3.73s on his swap car, so I know from experience. I don't think redlining first gear at 25mph is very beneficial. If we had a useful 8000 rpm rev limit like the s54, well then it would be a lot more beneficial! :p

Word, I could have Metric Mechanics build a custom trans+diff for perfect gearing, but it wouldn't be worth the price. :(

You'll be done for a while with that set-up, but then it will get a little boring just like any other amount of power that is still somewhat controllable. ;)

I think 3.15 is from the z3 and 3.25 is from an e28 535

3.15 came from the z3 I believe. 3.23 came from the z3 Mcoupe/roadster. 3.25 came from the e28 535.

[jrdeamicis]

Never said the diff was useless, just 1st gear. I had 4.10s when I started the swap and my friend has 3.73s on his swap car, so I know from experience. I don't think redlining first gear at 25mph is very beneficial. If we had a useful 8000 rpm rev limit like the s54, well then it would be a lot more beneficial! :p

Word, I could have Metric Mechanics build a custom trans+diff for perfect gearing, but it wouldn't be worth the price. :(

You'll be done for a while with that set-up, but then it will get a little boring just like any other amount of power that is still somewhat controllable. ;)

Thats what friends cars are for.
I just got back from driving my buddies 450whp GT35R M3. :)




3.15 came from the z3 I believe. 3.23 came from the z3 Mcoupe/roadster. 3.25 came from the e28 535.

For discussion

31 / 53 / 79

I think thats awesome. Funny enough my 2001 honda civic has the same gearing. :)


I wonder how much it would cost to have a slightly taller 1st. MMMMM

The 3.46 must be PERFECT

[e30polak]

For discussion

31 / 53 / 79

I think thats awesome. Funny enough my 2001 honda civic has the same gearing. :)


I wonder how much it would cost to have a slightly taller 1st. MMMMM

The 3.46 must be PERFECT

Yeah the 3.46 really is perfect! 8)

I would love to have a 6th for longer trips on the freeway...:(

[jrdeamicis]

Yeah the 3.46 really is perfect! 8)

I would love to have a 6th for longer trips on the freeway...:(

Ill sell my 6 speed for 3Gs

6 speed from E30, Auto M3 Driveshaft, Evo 3, Custom DSSR Custom Tranny Mount, JBR Lightweight flywheel, 330 clutch (fine splines on this box)

Let me know :)

[e30polak]

Ill sell my 6 speed for 3Gs

6 speed from E30, Auto M3 Driveshaft, Evo 3, Custom DSSR Custom Tranny Mount, JBR Lightweight flywheel, 330 clutch (fine splines on this box)

Let me know :)

I'd rather buy a used blower. ;)

Thanks for the offer though! :D

[mazur]

Here you go...3.46 with 245/45/16 tires


Gear Mph per 1000 RPM Mph @7000 RPM Mph @7000 RPM
--------------------------------------------------------
1 5.02 35 35
2 8.45 59 59
3 12.71 89 89
4 17.25 121 121
5 21.22 149 149



Gear Change RPM drop (change @7000) RPM drop (change @7000)
-------------------------------------------------------------
1 -> 2 -2846 (to 4154) -2846 (to 4154)
2 -> 3 -2343 (to 4657) -2343 (to 4657)
3 -> 4 -1844 (to 5156) -1844 (to 5156)
4 -> 5 -1309 (to 5691) -1309 (to 5691)

[jrdeamicis]

I'd rather buy a used blower. ;)

Thanks for the offer though! :D

For 3Gs you can have a new blower. :)