Taking the plunge...M70 to complete M73 and auto to M3 6 speed

[vwleadfoot]

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I've already gotten the M70/4hp24 out of the car, and have purchased a REALLY clean 94k mile M73. I've tried to get all the info together that I can but it's been a battle. Especially when all of the threads on it are so old and don't have pics anymore. My main concern right now is getting a chip set that has the right ignition curves for the higher compression M73 (M73 10:1 vs M708.8:1) while still using the M70 electronics/ECUs. I emailed Wolf (wokke) and he did respond, but not with the answers I need yet. Has anyone found an answer for this? Is Wokke the only place I can get this? Shogun?

I also need;

-The longer and correct crank bolt for using the M70 balancer on the M73 engine.
-Does anyone know if there is a guy who reseals ac compressors and PS pumps? Both worked fine but I just want to reseal them to be sure.
-I'd also like to put new seals in my perfectly healthy(but maybe leaking) 20k mile old BMW reman steering box. Is this a doable thing to do myself? Or is there a place anyone could recommend? Especially if it's local to Baltimore, MD....

After I'm done I will also be unloading a large amount of M70 stuff. 2 motors ,3- 7 pin 4HP24s(two known good), and whole bunch of other stuff leftover from 2 parts cars. If anyone knows an 8 series guy who could use it please turn them on to me.

If anyone here has other pointers please post them up here. Anything helps.

[moroza]

Compressor reseal? I had a good experience with Compressor International and an M50 reman they did. In my case, the compressor was a Denso PA17C, which is a fairly common compressor type fitted to many cars, all of which have the same seals and internals.

PS pump reseal? I've heard of kits...

Steerbox reseal? See here.

What're you doing for clutch and flywheel?

Looking forward to your build thread. That'll be a sweet ride!

[vwleadfoot]

Compressor reseal? I had a good experience with Compressor International and an M50 reman they did. In my case, the compressor was a Denso PA17C, which is a fairly common compressor type fitted to many cars, all of which have the same seals and internals.

PS pump reseal? I've heard of kits...

Steerbox reseal? See here.

What're you doing for clutch and flywheel?

Looking forward to your build thread. That'll be a sweet ride!

Thanks for the info. I'll be using the PMC adapter plate and E46 M3 clutch setup. It comes with a specially made flywheel that extends out from the engine to compensate for the thickness of the plate.

[a777fan]

Curious what the M73 is buying you over the M70?

[LappingLuke]

Curious what the M73 is buying you over the M70?

If nothing else, is +400cc useless?

[vwleadfoot]

Curious what the M73 is buying you over the M70?

M73 has more displacement, higher compression, and has roller rockers. My M70 was tired at 180k miles and starting to show it's 30 years of age.

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If nothing else, is +400cc useless?

Not useless at all.....

[LappingLuke]

Yeah I'd personally love to have an M70/3 or however one might like to name it in my 850Ci 6 speed car. When you finish you'll have a really neat ride. good luck!

[jimmythefish]

Master6 on here, Jay Stratton, might be a good resource to reseal your AC compressor and other pumps. I find that the M73 engine is just a smoother motor than the M/S70. Cool project, I have 3 E32 M70 cars, and installing a manual transmission in one of them could be interesting….maybe someday! I have family in the Baltimore area and if I get back in the spring and you have availability, I would love to see your project.

James

[shogun]

I also need;
-Does anyone know if there is a guy who reseals ac compressors and PS pumps? Both worked fine but I just want to reseal them to be sure.
-I'd also like to put new seals in my perfectly healthy(but maybe leaking) 20k mile old BMW reman steering box. Is this a doable thing to do myself?

In case you keep the original M70 steering gear box, you need a gasket set 32131134768, have done some steering boxes for M70, doable for a DIYer https://www.ecstuning.com/b-genuine-...t/32131134768/
same with the original 750 power steering pump , Seal Kit For Power Steering Pump Genuine 32411135880
AC compressor: Master6 https://www.bimmerforums.com/forum/s...on-JCS-master6

[Jormotors]

I was planning to do the same swap on my manual 750 but decided to stick with m70 for now. Hope to see you make some progress!

[vwleadfoot]

Reviving this thread for new pics. Test fitting E46 M3 trans to clutch and M73
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