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1974 140 manual swap (BW35 -> M400)

i've never done a swap like this so i am still figuring out what else i'll need; please feel free to chime in if you've been down a similar road

i have an 8-bolt flywheel otw but, besides that, i figure that ill also need;

1) throw out bearing
2) drive-shaft center carrier bearing/bushing
3) pedal assembly solution (i have a partial 1974 pedal setup laying about somewhere)
4) rear main seal assembly
5) flywheel bolts

i'm not sure if the 164 clutch cable will be the right length (i doubt it) so i'm also figuring to need a cable that fits whatever 140 pedal setup i use as well.

edit;

6) clutch alignment dealio
 
The 164 M400 bell housing doesn't fit the B20 engine. Also, the input shaft splines are larger as is the front seal housing that the T/O bearing rides on. The clutch cable is also completely different.

What you really need is an M410 from a '70 1800E or any later M40/41 that has the stronger gears. With an O/D trans you'll also need the special trans cross member.
 
I was going to say what hiperf said, but he already said it. It's just not going to fit.

Find a buyer for it (164 manual trans parts are very rare and valuable). Is the flywheel you have coming a B30(164) or a B20 flywheel? Not the same thing, not interchangeable, like the trans.

Then start shopping for b20 M41/M410 trans and parts instead. M410 being the much rarer version used for a brief period on the 1800E, the M41 being the one that was much more common.
 
hiperfauto, JohnMc; thank you. exactly what i needed to know but didn't pick-up on when researching.

the flywheel incoming is for a '74 b20 specifically.
also, i have an m40 and m41 (with some damage to the od unit) laying around, too; can i swap the bell-housing and still use the m400?

edit; nm the input shaft splines nixes that.
 
M400/410 bell housings are an integral part of the transmission as they retain the bearings and oil using a gasket like M45/46/47. M40/41 bell housings are a separate part so they're completely different and won't interchange.
 
alright, sure.
so am i understanding this right;

1) the m400/m410 are getrag boxes (different bellhousing design from m40/m41)
2) the m400/m410 from the b30 do not swap with the b20 due to input shaft/bellhousing differences
3) the m410 was produced for b20s in the 1800 for a very limited time
4) the m400 never was produced for b20s

?
 
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anyways seems the best foot forward is to liquidate what ive got in favor of better fitting parts considering how much differed across the few models & years.
 
alright, sure.
so am i understanding this right;

1) the m400/m410 are getrag boxes (different bellhousing design from m40/m41)
2) the m400/m410 from the b30 do not swap with the b20 due to input shaft/bellhousing differences
3) the m410 was produced for b20s in the 1800 for a very limited time
4) the m400 never was produced for b20s

?

1) According to this post they're made by ZF, not Getrag.
2) correct
3) correct, they were only used in '70 1800E's with manual trans AFAIK.
4) correct but it's possible to build one. That's what's in the race car in my sig. :)
 
Little steep and a bit far but they're not getting any easier to find.

M410

That's pretty close to me so if you want to spend the coin and the guy doesn't want to ship, maybe I can help facilitate that for you.
 
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Little steep and a bit far but they're not getting any easier to find.

M410

That's pretty close to me so if you want to spend the coin and the guy doesn't want to ship, maybe I can help facilitate that for you.

Damn, seems like a decent price given what M41s seem to go for. Wish I'd seen that sooner.

Since a '74 has the right shifter placement and wider tunnel I'd also entertain a T5 or one of the multitude of transmissions that fit in a 240. Might have to get creative with a bell housing adapter though. if you can't get the right bell housing (both B20 and B230 ones work) and adapter plate (one of them should mount the transmission upright).
 
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Little steep and a bit far but they're not getting any easier to find.

M410

That's pretty close to me so if you want to spend the coin and the guy doesn't want to ship, maybe I can help facilitate that for you.

I asked the guy, apparently he is willing to ship it. Probably in the neighborhood of $200 for shipping. Seems like a good deal for an M410 if it is working.
 


I'm doing two 1800E 410s with B20 bell housings now. One for the 1800s racing car and the other for the '68 122 wagon. Using the larger and stronger 164 input shafts with custom clutch discs with 164 splines. They are not easy to work on, some special tools are required, some of which were found and I had to make a puller for the output shaft bearings.



164 410 input shaft on the left M40/M41 on the right. Everything inside of them is about 25% larger and stronger. Good for racing and can handle a lot of torque and HP.

Parts are expensive and new syncros are very hard to find and some of the things needed including a new second gear were found in Sweden. I've now have a source there for NOS parts. The counter shaft bearings need be updated because the originals are weak.

hiperfauto and his brother Planetman helped me with a few things and they know a quite a bit about them as well.

I have five of them now and four of the rare B20 bell housings.



 
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There are three versions of ratios for M400/M410. I don't have exact numbers right now, but 1st gear ratios are like:
Early 3,1:1
Late 3,5:1
Racing 2,5:1 (This gear set can be found in some military applications)

By grinding down 164 shaft you can use B20 clutch disc.
 
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