Old style intake Manifold for M30

[Justinian]

Trying to get a few details together for trying to put a M90 with a dog leg trans from a 79 euro 635 parts car I have into my E30. Through this forum and other sites I think I have a pretty good idea about what it will take but I have a few questions still.

I've seen a few pics of the M90 used but the older tubular manifold was switched for the newer style with the 3.5 stamped in the side. Was this done because of clearance issues?

Also, does anyone know of any companies that provide shifter rebuild kits for the older style plate shifter assemblies? The one on the 635 is possibly bent.

Thanks!

Justinian

[euroshark]

Justinian,

VERY good engine and tranny choice, I used an M90 in my first 335i as well... It's a totally different animal than your standard M30B34 or even the M35!

The reason most people go with the later style manifold is because that's the way their motors came. I would recommend swapping to the newer one though, as it flows better than the old one. If you need a list of parts for the conversion I can help you out. In fact, I have pretty much everything you will need if you would like to buy all the stuff at once.

Not sure about the shifter plate rebuild, but you can easily find a replacement from a dealer or from someone on www.mye28.com or www.bigcoupe.com

Post some pictures of your E24s!

[Justinian]

Justinian,

VERY good engine and tranny choice, I used an M90 in my first 335i as well... It's a totally different animal than your standard M30B34 or even the M35!

The reason most people go with the later style manifold is because that's the way their motors came. I would recommend swapping to the newer one though, as it flows better than the old one. If you need a list of parts for the conversion I can help you out. In fact, I have pretty much everything you will need if you would like to buy all the stuff at once.

Not sure about the shifter plate rebuild, but you can easily find a replacement from a dealer or from someone on www.mye28.com or www.bigcoupe.com

Post some pictures of your E24s!

Shoot me an e-mail with what your willing to part with since I would be much easier than going through my local junkyard. It seems that they have everything I need and the guy who owns it is familiar with the swap.

I wish the euro 635 could have been saved but there was to much corrosion on structural sections to save and the interior is in awful condition. I did get to drive it a few time before the shifter linkage failed and it felt like an amazing motor and will really push the E30 well.

[Madhatter]

if the newer manifold flows better, why do people swap back to the older jetronic manifold and swap in M10 2L runners to get more power?

[PiercedE30]

I was about to say the same thing about the M10 runners being used on the M30.

[euroshark]

I've never heard of anyone swapping BACK to the old style manifold and fitting M10 runners for more power on a Motronic M30. On the L-Jet M30s I've seen it done, but from what I have read, the Motronic manifold is designed the way it is because it promotes better flow and better atomization, as well as improved midrange torque over the older style manifold. Not only that, but the throttle body bolt patterns are different from the Motronic to the L-Jet manifold, and the placement of the throttle body in relation to the AFM changes significantly with the L-Jet manifold, making it impossible to use the motronic style IVC...

Long story short, going from the Motronic style manifold to the L-Jet piece on a Motronic car would be hard, but going to the Motronic manifold on an L-jet car is easy.

If he stays with the old manifold, I'd definitely recommend the M10 runners though.

if the newer manifold flows better, why do people swap back to the older jetronic manifold and swap in M10 2L runners to get more power?

[rs4pro3]

the bigest issue with the old style manifold, is you can't put motronic injectors in it easily. So if someone is swapping there fuel injection to something newer they almost have to go with the newer manifold

[Justinian]

Thanks for the information. I will be using the original manifold since I have a complete parts car and do not want to try to source a swap motronic components.

What difference am I looking at with going with M10 runners?

[euroshark]

I've never seen any numbers, but from what I have read on www.firstfives.org the gain can be fairly substantial. Most likely worth the effort I'd say!