M127 swap to M189?!

[lagolag]

The more I read about Mercedes history from the 50's I am amazed how they came to use a bored out M127 2.2l engine to 2.3l and give it mechanical injection when you already had the M189 3l engine on the 170 hp, and there was a stronger version in the 300SL. There can't be much difference in weight and the size is similar so the price should have been basically the same and you would have avoided a lot of development costs, the 3l machine might not have been as revving but it would have been perfect in the Pagoda as a real Grand Tourer.
Has anyone here changed their M127 to M189, would be interesting to get feedback on that?!
Is it possible?
//Lars

[Vander]

M189 parts cost significantly more, which makes it cost prohibitive. It has a generator instead of an alternator, which the water pump is driven off the back. The fuel injectors are completely different, M189 in the W112 had a belt driven pump for the air suspension system. There are A LOT more components on the side of a M189 motor, I'm not sure it would fit in the W113 engine bay without a lot of reconfiguring.

[ja17]

The M189 engine was too tall to fit in a 300 SL or a pagoda. In the case of a 300SL, the factory installed the engine at a slant. Seems like an easy fix?  Not really, with the SL, the factory went to dry sump lubrication and a second "power dome" was added to the hood since the valve cover ended up on the drivers and the long intake runners on the passengers side. All kinds of special parts were unique to this engine. No other MB engine had the unique sound produced by a M189, M198, when they were asked to perform.

[Benz Dr.]

The 300SE is manifold injection but the injectors spray right in front of the intake valve so it is much closer in function to one of our SL engines. I would call it a sort of highbred engine in that it comprises aspects of both builds. And, you are right Joe, it is a large engine.

[ja17]

Yes, the early 300SE engines used a two plunger injection pump. The latter ones used a six cylinder injection pump like the pagoda. I owned a rare 1966, 300SE sedan (W108) chassis. This car had the M189 engine with a standard four speed transmission, and NO air suspension with the short wheelbase. Mercedes only made 2.700 in this configuration and they were all Euro Delivery. It was a blast to drive, fast and light with the aluminum block, short wheel base, no air suspension, no AC, roll-up windows, and standard transmission. It had the characteristic sound unique to those engines.  The car eventually succumbed to the salty roads of the north since it was may daily driver. The engine was extracted and sold to a new owner somewhere in Chile for his 300SE cabriolet!

[Benz Dr.]

Interesting story. I've worked on a 109 300 SEL with that engine and a 112 sedan RHD which was said to be a very rare car. Nothing sounds like 300 ( SL ) 

[lagolag]

Thanks all for your feedback.
It’s a tall engine, that's probably the main reason and yes this tall engine had to be leaned to reduce the build in height but the basic engine is always without all help units and as ja17, it did exsist in a basic version in 300se in the mid sixsties.

[Jack the Knife]

Surely it's not as tall as an M110?