'69 230 w/m110 build/swap
 

Just started buying pieces for my new project.

Interested in informational comments on "sleeper" hot rodded W114.

I have purchased a 1969 230 w/original drivetrain, sold as an original 35,000 mile car. Runs, interior looks almost perfect, no rust. It left Oakland yesterday, I should be able to pick up after X-mas.

Attachment 133812

I have a M110 and auto trans from a grey market 1985 280SE that arrived on island Friday and will be delivered to me Monday.

Just arrived a set of 16 x 8 Lorinser wheels for it from Poland.

Plans for the engine are offset grind crank, increase compression to 10.5:1, individual F/I throttle body's, custom rods, pistons, mods to head relative to changes. Only the block, crank, and head will remain. Change to coil on plug, serpentine belt system, etc

I've been trying to research building up this engine, but it seems no one completes the build or they just loose steam.

Over the last 10 years I have built/modified/restored 1979 Jeep Cherokee (401 stroked, custom pistons, rods, cams, heads, etc), 1972 Mustang, 1977 Corvette (on 3rd engine revision), 1995 YJ Jeep with Chevy 4.8 ltr Vortec/4L60 trans conversion, and just finishing building a Factory Five Racing 818.

Not necessarily bragging, just putting into perspective that I do understand some of the concepts, costs, and time required to make major changes.

The goal is not to make unfriendly outward changes to the cars appearance, just modern designed/performance drivetrain. Obviously it would be much easier to drop in a LS engine, but I want to keep this Mercedes. Plus the fact that the M110 is a Hemi is too cool not to try and build.

After I get the engine/trans I will be shipping off the crank and heads for their improvements. Does anyone know if anyone has a torque plate for the M110?

1) Two changes to the engine bay: deletion of the firewall-to-inner fender braces, and, relocation of battery to RF corner.

2) Re: Crankshaft & Rods
What would be the new journal size, source of bearing, width of bearing relative to journal width, and perhaps most important, the benefit of any possible change in stroke?

3) Re: Pistons & CR
Be aware that the combustion chamber configuration (including the piston top), valve placement, and spark plug placement are non-symmetrical. As a consequence, the shape of the piston top required to achieve the desired CR, and, good flame control will be a decidedly custom piece of work. You may have encountered pictures of M-110 pistons with off-the-shelf domes; they may yield the intended CR, but will result in very poor flame propagation, with its attendant detonation.

4) "Hemi"
The M-110 chamber is actually closer in configuration to the Mopar "Poly-sphere" chamber of the 1950's, than to that of the hemis.

The W114 chassis is said to be similar to the R107 chassis which is the 450SL to 560SL convertible platform from 1972 to 1989. If you put a Mercedes V8 in that chassis it would be faster and still have Mercedes parts. Trying to sell a W114 with a Chevy or Mopar under the hood is difficult and reduces the value drastically.

Frank, thanks for commenting.

Part of the overall build includes deleting the spare tire and pocket in the trunk. The battery will be located in that area. Cleaning out everything possible under the hood also for a clean look.

I have not been able to confirm if the M110 has a forged or cast crank. Obviously hoping for forged. I have not been able to find anyone that has pushed the envelope on maximum stroke, so not sure how far I can go until I open mine up. But my hope is I can get to 86mm. Carrillo sells an off the shelf rod for a Spidget that has a 1.77" dia and 1" wide end with several options for bearings. It is also close to the right length. If the crank is forged I can get it welded up, stroked and fit to the rods for $2k, if not it will be closer to $5k for a custom crank.

The benefit is displacement. Can't go wide, gotta go deep! Plus it will help with increasing the compression to my target static of 10.5:1

Custom Pistons will be required, each aspect actually. Looking to drastically reduce the weight of the assembly. The Carrillo rods are half the weight of stock, looking to do the same on the pistons. After the heads are complete I wil be sending a mold of the combustion chamber to aid in the design of the top of the piston. Increasing the stroke will alter the shape of the top of the piston and how far it extends beyond the top of the block and its shape.

I guess you can split hairs on the hemi shape, but it is rounded and has splayed valves.

This will take a few months to put together. But I did build my 818 from the ground up in 13 months, including paint.

Attachment 133827

Jeffery, thanks for taking time to comment.

I agree about the Chevy engine, that's why I bought a Mercedes M110.

I have already done a Chevy engine swap, build up a couple of V-8's, and 4's, but never a staight six. Looking to apply all modern engine technology to this engine. Honda K20 engines, with a 86 X 86 bore and stroke are getting +200 HP, hoping to apply some of the technology to get close to 300 HP out of this build. Probably won't make it that far, but should be a fun exercise. And who knows, maybe I get close to the power of that era's Mercedes V-8's with less weight.

I am enthusiastic about your project. There are materials available today that Mercedes engineers could not have dreamed of when designing the straight six. Thank you for sharing your experience.

I am a nuts and bolts level mechanic. Much of my experience has been diagnosis of wear, tear and broken parts that can be replaced. I learned how to rebuild parts and perform maintenance to extend the life of components. What you are planning is a higher level and very interesting.

It is an interesting project--might be worth while to see what AMG and other aftermarket manufacturers learned--and what they modified in order to improve on the M110's potential thirty years ago. There may be components available in Germany still on the shelf--good luck



Tim Kraakevik
kraakevik@voyager.net

Before you build the motor, fit it into the W114 and resolve any installation and mounting issues.

Out of curiosity, why didn't you start with a younger, hotter benz motor and go from there? Isn't a C36 power plant most of the way to what you are looking for?

-CTH

CTH, thanks for joining the conversation.

Good question about the C36 engine as a choice.

MB actually has a stable full of great engines to choose from. A few of the reasons I chose the M110; 1) paired to a non TCU controlled auto trans, 2) can be outfitted to match vintage year, 3) want to build an inline six, 4) possible increased flow offered by the Hemi head, 5) engine is strong enough to support mods, 6) well supported crankshaft with 7 mains, 7) head organized with exhaust on one side and intake on the opposite, 8) should fit my engine bay without major modifications and changes to suspension, 9) gives me the most flexibility to re-design, but not be too visible when you open the hood, 10) should be unique.

I am not constrained by time, money, transportation, sanctioning body, government regulation, etc for the buildup of this project. Only my imagination. This is an exercise of recreation for me, with the bonus of being able to drive it when I done!

1973-1976 W114s were built with the M110. 280/280C/280E/280CE


See above

They delivered the engine/trans Monday, just got a bit of time to look it over.

Trans fluid smells normal, maybe a little stale smelling. Oil looks medium clear, no weird colors. Not sure of the mileage.

Side view

Attachment 133874

Front view

Attachment 133875

Engine plate

Any insight on what I have other than a M110?

Attachment 133876

Anything special about the head?

Attachment 133877

Transmission plate.

Any helpful information?

Attachment 133879