E36 track m3 gearbox / diffs....

[isleofthorns]

Just installed a 3.91 in my 3.0l m3, which def makes a difference at pretty much any speed / gear.
Only problem is that it's going to chop off too much top end for some circuits -- now approx 134 @ 7000 in fifth.
I've noticed that the ratios for the evo 6 speed are more or less the same for 1-5 as the 5-speed, with sixth as a .83 overdrive - this would return the theoretical top end back above 160....
So....
Has anyone fitted a getrag 6-speed in place of a zf 5-speed? Any likely issues?
Thanks


Ps - I have a few bits and pieces for sale from an aborted e46 m3 project - Ap front / rear, intrax 1k2, s/s rear race box and anti-rasp, larini race cats etc ... Email / pm if interested

[swtmerce]

The getrag is not rebuildable which isn't good because the synchros often go. I believe the parts cannot be sourced. It's also a lot heavier than the ZF. You would need the box, slave, clutch/fly and 6 speed prop.

It's just as straightforward to swap for the E46 box which will be newer and most probably fresher. Not sure whether an OEM prop will mate it though. Probably will but don't quote me.

[isleofthorns]

thanks... hadn't thought about the f/wheel and clutch!
I know the box is not as strong, but i just figured it the easier fix than having to keep changing diffs for different circuits etc.

also, now trying decide between AP four pots front and rear, or 6pot/4pot?

[scz4]

isleofthorns said:

also, now trying decide between AP four pots front and rear, or 6pot/4pot?

From Thorney Motorsport website:

The E36 M3 has two choices from AP, a four piston kit and a six piston kit. The four piston kit is really all you need (even for racing) but you need to make sure your wheel choice is suitable.

[Mroad]

scz4 said:

isleofthorns said:

also, now trying decide between AP four pots front and rear, or 6pot/4pot?

From Thorney Motorsport website:

The E36 M3 has two choices from AP, a four piston kit and a six piston kit. The four piston kit is really all you need (even for racing) but you need to make sure your wheel choice is suitable.

4 pots are great on mine (with Pagid RS19's) although it's a lighter car now compared to stock. Previously I was running Performance friction upgraded bells/discs and pads which could only be described as OK/adequate on track.
With the AP 6 pots I think you need 18in wheels so slightly more expensive rubber is required too. The 4 pots only require 17in x 8in which is what I now run all round. A cheaper alternative would be to run standard Evo size rears all round (17in x 8.5in).

As for the gearbox, as has already been said sticking the slightly unreliable Evo 6 speed in is a backwards step. I pulled mine out (that started to give a slight baulk into 3rd) and plopped the 5 speed in. It also saves 9kg in weight according to my scales (not including prop weight differences).

[juliann]

isleofthorns said:

Just installed a 3.91 in my 3.0l m3, which def makes a difference at pretty much any speed / gear.
Only problem is that it's going to chop off too much top end for some circuits -- now approx 134 @ 7000 in fifth.
I've noticed that the ratios for the evo 6 speed are more or less the same for 1-5 as the 5-speed, with sixth as a .83 overdrive - this would return the theoretical top end back above 160....
So....
Has anyone fitted a getrag 6-speed in place of a zf 5-speed? Any likely issues?
Thanks


Ps - I have a few bits and pieces for sale from an aborted e46 m3 project - Ap front / rear, intrax 1k2, s/s rear race box and anti-rasp, larini race cats etc ... Email / pm if interested

Where do you think you'll exceed 134mph ?
The fastest E36 M3 3.0 speed trap recording during one of our Silverstone GP race meetings in 2010 was 131mph. (We don't allow 6 speed boxes). Most of the E36 3.0 racers cope quite happily with 3.91

ps If you happen to have a 4.1 diff or CW & P for the E46 (210mm) I'd be interested

Edited by juliann on Saturday 22 January 11:15

[swtmerce]

juliann said:

Where do you think you'll exceed 134mph ?
The fastest E36 M3 3.0 speed trap recording during one of our Silverstone GP race meetings in 2010 was 131mph. (We don't allow 6 speed boxes). Most of the E36 3.0 racers cope quite happily with 3.91

ps If you happen to have a 4.1 diff or CW & P for the E46 (210mm) I'd be interested

Edited by juliann on Saturday 22 January 11:15

Perhaps he drives it to and from track or goes to the Nurburgring? I had a 3.91 in my Evo (with 5 speed box) and I'm now going for a 3.64 for the previous reasons

EDIT: forgot to mention, he'll exceed 134 mph at Bedford GT.

Edited by swtmerce on Saturday 22 January 16:52

[isleofthorns]

I was about to say.....so far the car has only been used for trips to he ring and Bedford, both where it'll be on the limiter. It will do more uk circuits this year, which I why I wanted the shorter diff in the first place, but with hindsight, I should have done the sums first and gone for a slightly longer option, so I could do both on one diff.

Having said that, I bought yesterday a set of 6pot fronts / 4 pot rears, along with some 18" alloys and slicks - the 18's will help a bit with the top end - I would imagine another 5-10mph?!

I guess also a trip to have a map and a limiter rise would help.... My friends group n e36 does 8k... Has anyone had this done and or can recommend somewhere?

Thanks....

[audirmz]

Mroad said:

scz4 said:

isleofthorns said:

also, now trying decide between AP four pots front and rear, or 6pot/4pot?

From Thorney Motorsport website:

The E36 M3 has two choices from AP, a four piston kit and a six piston kit. The four piston kit is really all you need (even for racing) but you need to make sure your wheel choice is suitable.

4 pots are great on mine (with Pagid RS19's) although it's a lighter car now compared to stock. Previously I was running Performance friction upgraded bells/discs and pads which could only be described as OK/adequate on track.
With the AP 6 pots I think you need 18in wheels so slightly more expensive rubber is required too. The 4 pots only require 17in x 8in which is what I now run all round. A cheaper alternative would be to run standard Evo size rears all round (17in x 8.5in).

As for the gearbox, as has already been said sticking the slightly unreliable Evo 6 speed in is a backwards step. I pulled mine out (that started to give a slight baulk into 3rd) and plopped the 5 speed in. It also saves 9kg in weight according to my scales (not including prop weight differences).

Hallo Mroad.
I would like to ask you about the ap brakes 330mm 4pots.You have them fitted without spacers?They require only 17 x 8in wheels?Are you satisfied from their performance?They would be ok for a full weight m3 e36 evo?If you dont have a promblem i would appreciate it very much if you could sent me a picture from your wheels because the most which i find are 17 x 8.5in.Have a nice evening Giorgos.

[minerva]

I have the 6 pot on the front of a track car and I am sure that the original 7.5 wheels will fit with 25mm spacers. Not from personal experience, mind, because I have compomotives, but then there are 7.5 with greater offset.

[minerva]

By the way, where did you get your 3.9 diff? I quite fancy one of those....

[isleofthorns]

Thanks - I also think they would fit under my current 17" team dynamics - I think the problem then becomes cooling as in there would likely be only a few mm clearance....

Ref the diff... It's a bit of a bitzer... When taking the original diff apart, damage was evident with slipper unit, so I went for an upgraded custom unit from diffsonline. This was then coupled to a 3.91 cw&p from BMW's group n parts catalogue.

I think it also possible to use a cw&p from a standard small case diff, most likely e30, which runs this ratio -- I can't advise more than this though.... I'm sure somewhere here will have the answer

[Mroad]

audirmz said:

Mroad said:

scz4 said:

isleofthorns said:

also, now trying decide between AP four pots front and rear, or 6pot/4pot?

From Thorney Motorsport website:

The E36 M3 has two choices from AP, a four piston kit and a six piston kit. The four piston kit is really all you need (even for racing) but you need to make sure your wheel choice is suitable.

4 pots are great on mine (with Pagid RS19's) although it's a lighter car now compared to stock. Previously I was running Performance friction upgraded bells/discs and pads which could only be described as OK/adequate on track.
With the AP 6 pots I think you need 18in wheels so slightly more expensive rubber is required too. The 4 pots only require 17in x 8in which is what I now run all round. A cheaper alternative would be to run standard Evo size rears all round (17in x 8.5in).

As for the gearbox, as has already been said sticking the slightly unreliable Evo 6 speed in is a backwards step. I pulled mine out (that started to give a slight baulk into 3rd) and plopped the 5 speed in. It also saves 9kg in weight according to my scales (not including prop weight differences).

Hallo Mroad.
I would like to ask you about the ap brakes 330mm 4pots.You have them fitted without spacers?They require only 17 x 8in wheels?Are you satisfied from their performance?They would be ok for a full weight m3 e36 evo?If you dont have a promblem i would appreciate it very much if you could sent me a picture from your wheels because the most which i find are 17 x 8.5in.Have a nice evening Giorgos.

Yes the AP kit I have is fitted without spacers but I bought a new set of 17x8in MV2 (I think) style alloys all round with ET+40 offset, they are not official BMW wheels but copies, they are fine on track and only cost £250 for the set I seem to remember. The wheels fit fine although there is a tiny tyre rub on the arches on full lock at the front but that's due to the Z3 rack being fitted and the car is lowered on AST coilovers (225/45ZR17 Corsas on the front at the moment).
The AP's are great on my car, the Pagids probably make the combo although probably overkill on the road. I can't say if the 4 pots are up to coping with a full weight Evo, they are definitely a great improvement on stock and I'll bow to Thorney Motorsports knowledge mentioned above that the 4 pots are all you need on road or race.
Please bear in mind that my AP set-up is not the kit AP supply but custom made bells/discs and brackets with AP 4 pot callipers. Dimensionally it is the same though.
I'll try and sort out a photo.

[swtmerce]

Geoff Steel Racing, JC Racing and West Sussex Racing are three outfits that I know of that can supply you a built diff to your spec. I used to have a 3.91 from a West Sussex Racing built car (Kumho championship winner in fact) and my friend is having a 3.64 built using E90 M3 variable M diff internals from Geoff Steel.

[audirmz]

Mroad said:

audirmz said:

Mroad said:

scz4 said:

isleofthorns said:

also, now trying decide between AP four pots front and rear, or 6pot/4pot?

From Thorney Motorsport website:

The E36 M3 has two choices from AP, a four piston kit and a six piston kit. The four piston kit is really all you need (even for racing) but you need to make sure your wheel choice is suitable.

4 pots are great on mine (with Pagid RS19's) although it's a lighter car now compared to stock. Previously I was running Performance friction upgraded bells/discs and pads which could only be described as OK/adequate on track.
With the AP 6 pots I think you need 18in wheels so slightly more expensive rubber is required too. The 4 pots only require 17in x 8in which is what I now run all round. A cheaper alternative would be to run standard Evo size rears all round (17in x 8.5in).

As for the gearbox, as has already been said sticking the slightly unreliable Evo 6 speed in is a backwards step. I pulled mine out (that started to give a slight baulk into 3rd) and plopped the 5 speed in. It also saves 9kg in weight according to my scales (not including prop weight differences).

Hallo Mroad.
I would like to ask you about the ap brakes 330mm 4pots.You have them fitted without spacers?They require only 17 x 8in wheels?Are you satisfied from their performance?They would be ok for a full weight m3 e36 evo?If you dont have a promblem i would appreciate it very much if you could sent me a picture from your wheels because the most which i find are 17 x 8.5in.Have a nice evening Giorgos.

Yes the AP kit I have is fitted without spacers but I bought a new set of 17x8in MV2 (I think) style alloys all round with ET+40 offset, they are not official BMW wheels but copies, they are fine on track and only cost £250 for the set I seem to remember. The wheels fit fine although there is a tiny tyre rub on the arches on full lock at the front but that's due to the Z3 rack being fitted and the car is lowered on AST coilovers (225/45ZR17 Corsas on the front at the moment).
The AP's are great on my car, the Pagids probably make the combo although probably overkill on the road. I can't say if the 4 pots are up to coping with a full weight Evo, they are definitely a great improvement on stock and I'll bow to Thorney Motorsports knowledge mentioned above that the 4 pots are all you need on road or race.
Please bear in mind that my AP set-up is not the kit AP supply but custom made bells/discs and brackets with AP 4 pot callipers. Dimensionally it is the same though.
I'll try and sort out a photo.

Thank you very much Mroad.The only thing which must be cleared before to buy the AP's is to find a nice set wheels.It would be perfect if you couls sent a picture to have a look.