Bluemotion MZN gearbox, an alternative...

Menno

A2OC Donor
A lot of people are installing JDD gearboxes to AMF/BHC tdi's to temper the revs at higher speeds.
Downside is the (huge) gap(s) between 2nd to 3rd to 4th gear.

An MYP 6 speeder is much nicer, but hard to find and/or expensive, also the shorter shift throw is not always or sometimes appreciated. Or an added 6th gear on your original AMF/BHC/ATL, which comes at a (hefty) cost.

A GRJ from an ATL tdi 90 is a good compromise, but can be also hard to find and makes use in standard form from DMF. If you would use this one, could it be used with a single mass flywheel? And would the starter motor from the ATL be required too? I didn't dare to have a go at it, so;

Enter a MZN (or MAL, MNY, MZK) gearbox. In my opinion it sits between a GRJ and a JDD gearbox in terms of gear ratios.
They're also fairly cheap and plenty to be found in comparison with the above other options.
I've done some research on Google (don't forget to put your b*llSh*t filter on....😉) and found that some people did install this gearbox successfully on an A2.

So having involuntary time off, I had a go on it too.
Modifications is cutting a piece out of the original hinge point, add some spacers between gearbox support/hinge and swap the driveshaft flanges from your original gearbox. That's it.
Ofcourse it's nice to first put some fresh new seals and sleeve for the clutch bearing in, and if your clutch is not so fresh, put a new one in too.

The advantage (imo) is that the ratios are not as steep as the JDD, but you're still benefit the lower rpms at cruising speeds.

Well, maybe you all know about this already, and I'm talking b*ll*cks, etc. But I'm happy with the result so far, and it didn't cost me an arm and a leg, and "sharing is caring".

Here some comparison between an EWQ (in white, standard AMF) and a MZN bluemotion gearbox (in blue).
Tyre size is 195/50-16 and display is in mph (especially for you beautiful lot) ;)

Screenshot_20200403_221706_com.robgreen.gearspeedcalc.jpg

Screenshot_20200403_221727_com.robgreen.gearspeedcalc.jpg

And here EWQ in white vs JDD in blue, tyre size also 195/50-16.

Screenshot_20200403_232410_com.robgreen.gearspeedcalc.jpg

Screenshot_20200403_232416_com.robgreen.gearspeedcalc.jpg

As a note: I don't want to slayer JDD gearboxes! It is a great conversion and is usefull to get noise and mpg down to great levels.
In fact, I was searching for one with acceptable mileage and pricing, but wasn't able to find and purchase one.
The MZN came around as an alternative, and became the weapon of choice 😉 .



Aloha,
Menno.
 
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dj_efk

A2OC Donor
Hi @Menno

This is interesting. Can you comment (for the benefit of newbies like myself) on what A2 you have that is the subject of this conversion? Also what do you mean by hinge point - Could you share any Pics for reference?

Finally, how does she drive? Whats the flexibility like in top and the drive ability in the gears / going up hills etc.? Any impact on fuel consumption that you’ve noticed? Noise?
 

Menno

A2OC Donor
Yes, sorry, the A2 in my case is a 2003 AMF Tdi.
It's remapped (thanx to @timmus) and has around 100hp, torque I guess in the range of 245nm.

Here a pic of the altered hinge point on the gearbox before;

IMG_20200404_091505.jpg

After;

IMG_20200328_194414.jpg

The drive is not very different in first and second, they have more or less the same ratio.
In third the step is a tad higher, and the same goes for fourth and fifth.
It's more now (in contrary to an EWQ) 1, 2, 3¼, 4⅓, 5½ "ish" (is this sounding somewhat clear?).
Where the JDD is almost in 3 a 3½ and 4 almost a fifth gear in contrary to the original EWQ box. This is very nice for highway cruising, but I don't know if it's very convenient for town and city driving.

To be honest I only drove it now for max half an hour on some 50/80 and 100km/hr roads.
It feels OK, and thanks to the remap it pulls the longer gears easily.
At 100km/h it sits at 2000rpm in top, just before the power band.
Imo good enough to pull away without having to shift to fourth.

The lack of noise is the best part, it's less noisy at higher speeds. The engine really starts to let herself hear from 3000rpm.
With this gearbox you have roughly all the daily required speeds on highway use from 2000 till 2750rpm in top Gear.

Fuel economy I don't know yet, but the dashboard gave lower consumption on a flat piece of tarmac at 100km/h.
Personal, the modification was done to temper engine noise, and fuel saving is a nice bonus.

Speed holding at inclines........ Well, err, I'm living in Holland, the flattest land in the world..... So that's not an issue to me, but I guess it can handle some hills.

More pic's starting here. Beware there are some JDD boxes pictured in the thread, which are posted by forum members.
To be clear; my box is a MZN.


If there are questions, I'm willing to answer as good as possible.
 
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dj_efk

A2OC Donor
It’d be interesting to know the drivability on fast-flowing but hilly roads if you do ever drive it somewhere like that / that isn’t completely flat.

Great write-up. Like earned.
 

Menno

A2OC Donor
It’d be interesting to know the drivability on fast-flowing but hilly roads if you do ever drive it somewhere like that / that isn’t completely flat.

Great write-up. Like earned.
If you're doing 70mph with this MZN box you're at approx. 2250rpm. Quite fast (I'm an old & slow f*rt 😉) and power should be (remap!) on tap, so I guess sufficient to attack some hilly roads.
 
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dj_efk

A2OC Donor
For sure this sounds like an ideal solution for the British motorway network if you can’t stretch to the 6 speed conversion - I tend to chug along at 75 or so myself if I need to be somewhere (65-70 otherwise), this means you sometimes need to overtake marginally slower vehicles via blips of 80 mph+ before pulling in / settling back again.
 

timmus

A2OC Donor
Goed gedaan, Menno. Echt Mooi. :)
If you're doing 70mph with this MZN box you're at approx. 2250rpm
The factory EWQ gearbox, fitted with a a 0.659-ratio longer 5th, turns 2270rpm at 70mph. So, it seems that the MZN gearbox results in a 5th gear of the same length, but that spaces all gears evenly, rather than having a huge jump between 4th and 5th. Winner.

Cheers,

Tom
 
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Menno

A2OC Donor
Tom, de A2 Tovenaar, dank u wel!

Exactly! All gears slot together, so there's no "riding around and minding" the drop in revs.

Just dumped the old EWQ at the breakers and collected my deposit.
Was a short distance drive, but with the new box I'm as happy as a puppy!
 

Howey

Member
Very informative are seals same in each box for ordering purposes and how much are they?
 

Menno

A2OC Donor
Seals are in the range of €5 - €15, you look them up on Google, and pick the price or shop you like.
As far as I know the seals are the same for an EWQ and MZN.

L/H gearbox/flange seal 15263
R/H gearbox/flange seal 39727
Seal for clutch bearing sleeve 101 776

Now, the seal for the sleeve you don't have to buy separate if you're buying the sleeve itself, because it comes with the seal pre installed.

IMG_20200404_165339.jpg
 
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dj_efk

A2OC Donor
Goed gedaan, Menno. Echt Mooi. :)

The factory EWQ gearbox, fitted with a a 0.659-ratio longer 5th, turns 2270rpm at 70mph. So, it seems that the MZN gearbox results in a 5th gear of the same length, but that spaces all gears evenly, rather than having a huge jump between 4th and 5th. Winner.

Cheers,

Tom
@Menno, looking at the first table / graph again (comparison of standard vs. MZN gearbox), it seems you need to rev out 3rd a bit to 3000 RPM in order to change up to 4th and still be within the powerband at around 2000 RPM - 4th to 5th looks like a smaller gap between them of around 500 RPM only, which is much more preferable and usable on hilly A roads & motorways.

I would imagine for 30 MPH limits the engine should just about be OK on light throttle cruising at 1500 RPM, although I would have thought you'd need to change down to 3rd for even lighter acceleration?

Overall, I'd say this is about the limit you'd want to go in terms of optimal gear spacing: As @timmus says - winner!
 

Menno

A2OC Donor
@Menno, looking at the first table / graph again (comparison of standard vs. MZN gearbox), it seems you need to rev out 3rd a bit to 3000 RPM in order to change up to 4th and still be within the powerband at around 2000 RPM - 4th to 5th looks like a smaller gap between them of around 500 RPM only, which is much more preferable and usable on hilly A roads & motorways.

I would imagine for 30 MPH limits the engine should just about be OK on light throttle cruising at 1500 RPM, although I would have thought you'd need to change down to 3rd for even lighter acceleration?

Overall, I'd say this is about the limit you'd want to go in terms of optimal gear spacing: As @timmus says - winner!
Hmmm, difficulties for me is to recalculate mph to km/hrs....... It's my problem, I've never been any good with numbers or mathematics......

But let's put it like this (in my opinion!) ;

1) If you have a bog standard AMF, just keep the EWQ gearbox. It can cope with it and will get you from A to B in comfort and no need to shift once you're in top on the highway.
Or the maximum for a standard AMF; a GRJ gearbox from an ATL 90 pk A2, which is a tad shorter geared then a MZN, but will have just enough puff/oomph(?) to pull the longer ratios.
Sadly, there's not a lot GRJ gearboxes wandering around to be mated with AMF's.

2) an AMF with remap requires a gearbox which is longer. It's got enough puff from 2000 rpm to pull in 4th and 5th. A GRJ is a good contender (again) but maybe hard to get.
A JDD is in my opinion too long geared, certainly for a standard AMF, but even a remapped one will be wanted to be driven like it's stolen to counter the drop in revs in 3 and 4.
If I had a remapped ATL 90, I would consider a JDD. This engine benefits from a VNT turbo which has more puff in sub 2000 rpms, and could pull the longer JDD gears........ In fact, the JDD would have a hard time to handle and stay in one piece from the remapped ATL hammering I guess.....
An MYP would be a better choice, or an added 6th gear to your GRJ if you're a posh guy or madam 😉.

Untill now I didn't drove my new setup much, because my employer put me on ground (AOG they call it in my profession(simple mechanic by the way)), so no need to get back and forth to work.
But, the times that I'd drove it, it didn't disappoint me at all! It goes just the same as always, no need to put some extra revs in to catch a drop in rpms, just drive it like I normally would with the bonus of low rpms at highway speeds.

30mph is the equivalent of 50/60 km/hrs I guess, and I'm now sticking to third gear. Because it is low enough in rpms, but also keeps it in the power band.
Sure, it's possible to put it in fourth at these low speeds, but the revs are too low to let the engine pick up speed in normal and healthy manner in my opinion.
Personally I think 1750/1800 is the lowest rpm an AMF should be exposed to in fourth and fifth gear to be at least able to go forward if the driver asks it to do so.
In the first three gears it can pull lower rpm's IF the gears are not too long, this is crucial!

Again, I'm not saying an JDD is inferieur, but a lot of reading on fora gave the same downfalls; the big gaps and not evenly spread ratios when combined with a wastegate AMF standard or remapped.
You can look it up here on A2OC... Initially I was going for a JDD too.

I'm better off with a MZN for my kind of driving style, but make your own choices, and go for what suit your needs.
 
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Menno

A2OC Donor
Thanx @greywolfhound for your kind words!

When I was 14/15 I wanted to know all about bikes.
Dutch motorbike magazines didn't gave me the satisfaction I was craving for...... But you lot had "Performance Bikes magazine"......DOH! Porn magazines are easy, you just watch it, but man did I care about that? NOPE, Performance Bikes was it for me!
Struggled a lot to understand what they where on about, but I managed little by little..... Guess it improved at least something 😉.

In my current job I'm working with Swedes, Italians, Icelandic, Morrocon and Spanish people (some funny Brits and an Irish bloke too....can't understand the last one sometimes, but man he's REALLY funny 😂) and your beautiful language is connecting and makes us understand each other......... So please don't be ashamed, but be proud on your language!
 
0C478DCF-2DD2-4C87-B048-95CAD6900962.jpeg
Thanx @greywolfhound for your kind words!

When I was 14/15 I wanted to know all about bikes.
Dutch motorbike magazines didn't gave me the satisfaction I was craving for...... But you lot had "Performance Bikes magazine"......DOH! Porn magazines are easy, you just watch it, but man did I care about that? NOPE, Performance Bikes was it for me!
Struggled a lot to understand what they where on about, but I managed little by little..... Guess it improved at least something 😉.

In my current job I'm working with Swedes, Italians, Icelandic, Morrocon and Spanish people (some funny Brits and an Irish bloke too....can't understand the last one sometimes, but man he's REALLY funny 😂) and your beautiful language is connecting and makes us understand each other......... So please don't be ashamed, but be proud on your language!
Never to old to ride a motorcycle..no it’s not me 🤣..
 

sco

A2OC Donor
Yes, sorry, the A2 in my case is a 2003 AMF Tdi.
It's remapped (thanx to @timmus) and has around 100hp, torque I guess in the range of 245nm.

Here a pic of the altered hinge point on the gearbox before;

View attachment 62857

After;

View attachment 62858

The drive is not very different in first and second, they have more or less the same ratio.
In third the step is a tad higher, and the same goes for fourth and fifth.
It's more now (in contrary to an EWQ) 1, 2, 3¼, 4⅓, 5½ "ish" (is this sounding somewhat clear?).
Where the JDD is almost in 3 a 3½ and 4 almost a fifth gear in contrary to the original EWQ box. This is very nice for highway cruising, but I don't know if it's very convenient for town and city driving.

To be honest I only drove it now for max half an hour on some 50/80 and 100km/hr roads.
It feels OK, and thanks to the remap it pulls the longer gears easily.
At 100km/h it sits at 2000rpm in top, just before the power band.
Imo good enough to pull away without having to shift to fourth.

The lack of noise is the best part, it's less noisy at higher speeds. The engine really starts to let herself hear from 3000rpm.
With this gearbox you have roughly all the daily required speeds on highway use from 2000 till 2750rpm in top Gear.

Fuel economy I don't know yet, but the dashboard gave lower consumption on a flat piece of tarmac at 100km/h.
Personal, the modification was done to temper engine noise, and fuel saving is a nice bonus.

Speed holding at inclines........ Well, err, I'm living in Holland, the flattest land in the world..... So that's not an issue to me, but I guess it can handle some hills.

More pic's starting here. Beware there are some JDD boxes pictured in the thread, which are posted by forum members.
To be clear; my box is a MZN.


If there are questions, I'm willing to answer as good as possible.
Nice job on the write up Meeno with some clear conclusions on the suitability of this swap. One question though: the chop on the gearbox casting - does it definitely have to be that brutal as that has seriously weakened that boss - those webs won't have been there just for the look of it.

Simon.
 

timmus

A2OC Donor
and your Dutch not that anyone would guess
Having spent a few very enjoyable sunny afternoons with Menno, and having lived in the Netherlands for a few years, I can definitely tell that Menno is Dutch. Indeed, I can hear Menno's voice saying the words he's written. I hasten to add that this is certainly no criticism of his English, which is vastly superior to my limited Dutch, but instead a pleasant reminisce about last year's adventures through continental Europe ... back when we were all free! :)
 
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