Originally Posted by Mark DiSilvestro
The OP stated a 200 M115, which would be a 4-cylinder gasser with a side-draft Stromberg carburetor and about 90 hp.
As for gas mileage, many years ago I replaced a '72 W115 220 4-cylinder with a '72 W114 250 6-cylinder. both were automatics. The six gave about 1-2 mpg worse than the four, which was worth it for the added smoothness and power. Although my 220 four did seem to rev more easily on the highway.
In addition to rear-end gears, driveshaft, exhaust, plumbing, wiring, and adapting any accessiories you might now have on your 200, there may be issues with needing stronger front springs and relocating the radiator to fit the longer, heavier M180 six.
I'd suggest trying to find and inspect a complete 230-6 version before you decide.
Otherwise, for the simplest performance upgrade, I'd be more inclined to convert your existing 200 4-cylinder to a stick-shift. I might have been much less inclined to get the 250 if my 220 had been a stick.
Happy Motoring, Mark
Yep it's a gasoline engine. About the diff, I saw the difference in the gear ratios at the mb classic wiki and it isn't that big, I think that could be done later. What about the transmission? Could I use the same tranny or definitely change it?
This is just my plan B in case the engine fails the tests and must change it. I would go for a more powerful engine with similar fuel consumption like the six cyl from the 230.6. And also for the future if I come across a cheap and more powerful MB engine to drop into my engine bay
About the auto to manual transmission change, does it really make a difference? Because I read at the specs that it only delivers 5 more km/h of max speed and in fact with auto transmission the acceleration is higher, 0-100 km/h is 15s and with a manual is 15.2s. So I'm not sure if it would be a great idea changing it. I know driving a stick is more fun but I already have the auto so is cheaper haha. When I get to upgrade the engine I would definitely change it to stick-shift so I can do burnouts and drifts
I am a fan of a k-jet m110 DOHC motor. The motor came in w114/115 chassis cars in the d-jet and carbed flavors, but the carbed versions apparently are anemic, and the d-jet is rare with a lot of electronics. The k-jet is fully mechanical and requires little-to-no wiring. The injected versions of the engine may be higher compression, but the 185 hp vs ~130 for the North American carbed version is pretty significant. Add a manual transmission, and there's a lot of fun to be had.
But if going with an automatic, I would be tempted to squeeze the most power possible in there. Apparently the m104 engine can provide a lot of power. I am not sure if you could squeeze a v8 into a w114/115 chassis car. They do sit on the same subframe as the 107 chassis that is most v8s.
That would be fun, I love the growl of a powerful V8. I would consider this for the future, not for my daily driver since those V8's are thirsty. Maybe using that combination with a lighter MB for drag racing and weekend fun
The engine bay of W114/W115 is quiet big and has lots of space so I don't think it would be a problem fitting a V8 there with some little mods.