W123 200 Petrol Engine Change to 280

[vrsmatt99]

Good evening everyone,

This is my first post as I have just bought my first Mercedes!
I have got a 1982 W123 200 Petrol model as a project, It doesnt have an engine or gearbox but is otherwise complete and very solid.

I was looking at putting the 6 cylinder engine out of the 280 model in.
Can anybody advise if this is possible and the amount of work involved?

I have restored a few cars so doing the work isnt a problem, just need to have a clearer idea of what is required!

Cheers.

Matt

 

[nick mercedes]

It would go in allright, but you'd need the engine and box and the exhaust.

Why not put a diesel in it?

 

[vrsmatt99]

Hi Nick,
Thanks for the reply, Is it much work to put the M110 Injection engine in if the original was a carb ening?
Also will the rear axle from the 2.0 be ok with the 2.8.
As for the diesel option, This would be a weekend car so Fuel economy isnt an issue and I want something that will have a little bit of power too!

Cheers

Matt

 

[nick mercedes]

280 is not the best engine, heavy and uses lots of fuel, you may as well fit a V8 from a 126.

Wiring is always going to be an issue with what ever you fit.

 

[nick mercedes]

The way to go:

Mercedes Prosjekt Photos by Ksteen2 | Photobucket

 

[vrsmatt99]

Thanks again Nick, Ironically a V8 is a strong possibility too!!
I know that will be a lot of work and was thinking if there was something a little simpler to fit but more powerful than the original engine.

Cheers

Matt

 

[chrisd87]

If you're just looking for a little more oomph, might it not be easier to fit the 2.3 litre version of the M102 engine, as fitted to the W123 230E? This engine has 136bhp as opposed to the 109bhp of the 200, so not a huge improvement, but would probably be fairly simple to fit.

 

[stwat]

If you're just looking for a little more oomph, might it not be easier to fit the 2.3 litre version of the M102 engine, as fitted to the W123 230E? This engine has 136bhp as opposed to the 109bhp of the 200, so not a huge improvement, but would probably be fairly simple to fit.

It's the extra torque from the 230 that makes a big difference.

 

[219]

It is certainly possible to fit the M-110 - you would best find a complete donor car to get all the associated bits : engine , gearbox , diff . Various electrical modules .

The 110 weighs a lot more than the 4 cyl , so you need the correct front springs , and the correct front brakes , rear brakes I think are the same . Is your existing car an auto , you may need the radiator from the donor car if an auto . Speedo will be a different ratio too .

If you find a rusty or accident damaged 280 , they usually have a higher spec than lower models , and little details like extra chrome trim over the front air vents , below the rear lights etc to set them apart . Around the inside of the door windows on a 280 are trimmed , unlike the bare metal on the rest .

Depends how far you want to go .

 

[vrsmatt99]

Thanks everyone for your help.
My original plan was to fit a V8 as the car is a project car and I know its going to be some work, but then thought what about other engine that were originally avaible in the W123.
It appears that either the 2.3 or the 2.8 are still going to be quite involved, so if its a major job whatever the engine. I think im going to stick with the original plan and put an M117 V8 in it!
Wish me luck!

Cheers

Matt

 

[rifiki]

I think Pratical Classics magazine did a V8 conversion a few years ago.

 

[vrsmatt99]

I saw that one yes, a Grey coupe I think,
Ive also checked out the guys build thread and it gives quite a lot of useful info.

I know Its going to be a bit of work but im looking forward to getting stuck in!

Cheers

Matt

 

[backlane41]

Martin Marrocco of Malton North Yorkshire is an expert in the V8 conversions on w123s. I have one, and it's a fabulous car.

 

[Druk]

Martin Marrocco of Malton North Yorkshire is an expert in the V8 conversions on w123s. I have one, and it's a fabulous car.

Welcome to this forum Tim. . Some interesting folk on here.

Derek.

 

[Bellow]

What about the straight sixes used in the 190 (2.6 12valve) and W124 (12 and 24valve)?
Do they drop in or do they require too much electrical/electronic support from the donor car?
They'd be more efficient and lighter (to the benefit of handling) than a V8 and a 3.0 24 valver can't be far off an early V8 power wise. Diff matching would be easier I'd imagine - unless there's a range of diffs that fit the W123 - is there?

 

[grober]

Depends on how much originality you want to go for. You would need to go for the M110 or M102 as they were the engines fitted to the production models. Anything else would detract from the cars orginality and possibly value. Stick in a V8 if you want but that turns it into a HOT ROD. It will be a hoot to drive and may attract a premium over an average W123. Doubt if it would climb to the dizzing heights of a tastefully converted W123 M110 though? Best of all would be to emulate a tuned M110 machine but then you are into big money. Mercedes Spezialist für Tuning und Oldtimer - VÄTH - M110

 

[Druk]

My experience of the M110 is they're greedy, underpowered and rattly old things you wouldn't want anywhere near the front of your car. Fit the 4cyl M102 and it will be fine.