Best engine for a w123? - PeachParts Mercedes-Benz Forum

William73 · #1 05-20-2006, 09:59 PM

I have a '80 w123 (used to be a 300D) with no motor or transmission. What would be the best Gas engine to put in it? I'm on a budget so lets not get crazy. If I can't find a M.B. engine I might have to put an American V8 in it. I know most of you wouldn't want that to happen so give me some good advise. Thanks for your input, Will.

t walgamuth · #2 05-21-2006, 09:34 AM

the most powerful engine offered was the 280e euro. with that engine it is a pretty peppy performer. i have one of these with a five speed.

but if i were starting with a diesel car i would prob put in a 300turbodiesel. this is a good option that you can do for not too much money and when finished you can sell it. something you might not be able to do with an merican engined benz.

just me. but why ruin a good benz with a 'merican engine. i have thought about it though but never done it.

the biggest plus (maybe the only one) is that you can be the only one on your block with an merican engined benz.

tom w

mbc43amg · #3 05-21-2006, 09:10 PM

If you'd be willing to put an american V8 in it, why not put a German v8 in it instead? I have a '98 C43 4.3L AMG engine with about 65K miles on it for sale. Long block. Make an offer; I'm not looking for too much.

William73 · #4 05-21-2006, 11:15 PM

I would put a M.B. V8 in it if the price was right. Where is yours? does it come with a transmission? How much do you want for it?
One reason I would use an American V8 is cost. I can buy a beat up pickup with a V8 and an automatic trans. for around $500. Some American V8s don't cost much to rebuild. After market intake manifolds, headers, carbs, etc. are affordable. Parts like oil filters, gaskets, timing gears and chains, etc. are easy to get and don't cost too much.

mbc43amg · #5 05-22-2006, 12:19 AM

no, just longblock engine like I said (no tranni, wiring harnass, fuel system, etc...). I sure won't go near that price tho. (it is an AMG engine after all

)

BobsterMan · #6 05-22-2006, 03:08 AM

Hi, William73... I rolled in a couple of months ago with a similiar interest (but no car yet) in a 123 coupe, or the predecessor. I was thinking of an L6 because of the fit... the old Ford from 60's... the 200 cu in can have 7 mains and will go to 7000 rpm with light factory pistons. However, the bunch here convinced that the MB 2.8 L6 is a good deal... hp, torque, and apparently a lot of good used ones around.

Jim B. · #7 05-22-2006, 04:33 AM

Do any smog rules apply in your state for a 1980 car?

In California, diesels are exempt, but for gas cars, you can't install an engine older than the model year of the car (for example)

It varies by state...Michigan has NO annual/biannual inspection; you could rip out the catalyst, smog equipment and be good to go for years. May be a different situation though when you transfer ownership.

Tom is right about the 280E, that is the hot setup, especially with a stickshift, but W123 280E cars were pretty scarce on the ground back in the day, but they were the fastest/biggest available for the car. Most Americans went for the 240/300 engines.

IF you could find a Chevy or Ford small block, and could find written examples of people who had made that swap, it would be worth it make a sleeper muscle car to enjoy..with the "Diesel" script on the deck lid.

And maybe a little sticker (saw one on a Volvo today) "Death cab for cutie"

t walgamuth · #8 05-22-2006, 06:21 PM

Quote:

Originally Posted by BobsterMan

Hi, William73... I rolled in a couple of months ago with a similiar interest (but no car yet) in a 123 coupe, or the predecessor. I was thinking of an L6 because of the fit... the old Ford from 60's... the 200 cu in can have 7 mains and will go to 7000 rpm with light factory pistons. However, the bunch here convinced that the MB 2.8 L6 is a good deal... hp, torque, and apparently a lot of good used ones around.

not to be a wet rag but i bet the 'merican i 6s are way to long and some are too tall too.

best choice if you must put an merican engine in imho is the small block ford v8. it is very narrow like a benz v8 and light too. chebby v8s will interfere on the fenders i think.

tom w

BF_JC230 · #9 05-23-2006, 12:47 PM

This is old news to those that know me - but here is my Fordcedes with a 3.0 V6...before the supercharger....

I was on a budget when my father and I built this - I was 15

The w123 at $500 was rotted out and needed A LOT of work, and the donor Ford car was free - so the price was right...

But I agree to try and keep it pure - if you can, if not it is better to me, than sending it to the bone yard or crusher...

Jake

BobsterMan · #10 05-24-2006, 11:18 AM

Quote:

Originally Posted by t walgamuth

not to be a wet rag but i bet the 'merican i 6s are way to long and some are too tall too.

best choice if you must put an merican engine in imho is the small block ford v8. it is very narrow like a benz v8 and light too. chebby v8s will interfere on the fenders i think.

tom w

Tom... I'll give you the height issue for now because I haven't made the exact measurements, and the Ford s/b is narrow (is it 60 degrees?), though the heads on the 351 can make it little wider.

However, at 385 pounds, how big can the 200 be? Yes, the 300 in much larger. The ultimate demonstration of hybridization (bastardization???) would be to use the industrial 200 from a farm swather, and it is still a player for me.

t walgamuth · #11 05-24-2006, 11:14 PM

hey bobster.

dont take my guess word for it. measure and see. my thoughts are just a very preliminary guess.

i once dragged home a chevy II four cylinder thinking i could put it in my 61 bugeye sprite whose engine was absolute rubbish. i sat the chebby on the ground next to the front end of the sprite and the top of the valve cover would have protruded about 6" out of the hood, so with adequate ground clearance under the chebby pan i would have needed about a 12" tall blister!

i dragged out my peterson engine swapping book from 75 and looked for the ford I-6 dimensions but they only showed v8s. they figured everyone would be pulling out the sixes and stuffing in 8s.

good luck.

tom w

William73 · #12 05-29-2006, 12:40 AM

I was thinking that I might want a Dodge engine in the Benz now. Since Chrysler and Mercedes are now one, would it be less offensive to the purists out there if I had a Chrysler Corp. engine in it. A local junkyard will sell me a motor and trans out of a Dodge van for $400. Still, I would love a Mercedes engine for it.
Oh, by the way. Me taking interest in this car is what is keeping it from being crushed so it's not like I'm ruining a good car, I'm saving one.

t walgamuth · #13 05-29-2006, 07:18 AM

ouch!

dodge engine is a lot wider than any benz motor.

if you must have a v8 why not a benz v8? i have seen several offered for sale with 380 or 500 benz motors. the weight will be much less than any mreican motor except perhaps small block ford, and lots of stuff will bolt up and work. then you will only have to deal with the exhaust header hitting the fender well and not a lot of other incidentals.

if you want a benz with an meircan v8 why not buy one already done? ifyou run a search i bet you can find one.

i know you are looking for a cheap way to power your 123 but a good used benz motor will work and when you are done you will have less money in it and it will be right.

going the merican engine route is a lot more work than you are imagining.

tom w

William73 · #14 05-29-2006, 11:54 PM

I'll tell you the whole story. My neighbor somehow came to own a '77 300D and an '80 300D. The '80 ran and drove but didn't have reverse. Also the interior was in pretty bad shape. The '77 had a good trany and great interior but didn't run.
He wanted to put the good engine in the '77 and keep the bad engine and trany to rebuild and keep as a spare. He also wanted a few parts off the '80. He told me that if I pulled the engine out of the '80 I could have the rest of the car.
I went a little further and pulled both engines and tranys. Then I put the good engine with the good trany and also swapped over a bunch of parts from the '77 engine onto the '80 engine and then put the '80 engine with the '77 trany into the '77 300D. So now he has a '77 300D with an '80 engine that has nice interior.
I now have an '80 300D with no motor or trany that has bad interior and is missing a few parts. The body is straight with no rust. All the glass is good but the car needs a paint job. I just got some window switches from Ebay but I still need taillights. I have to redo all the seats. I think someone was trying to smuggle Triscuits by stuffing them into the back seat. I have some mechanical skills and some time on my hands but I don't have much money. I would love a M.B. V8, or turbo Diesel, with a trany to put into it. I also think it would be cool to have a 440 with a six-pack in it but I don't think it would fit without chopping up the car.
If I do put an American V8 in it, I don't want to modify the engine compartment so that in the future, when I have the money, I can put a M.B. engine in it.
If I don't get this car running and driving by the end of the summer I might have to get rid of it and I don't know what will happen to it.
So now you can better see the situation I am in.

BF_JC230 · #15 05-30-2006, 12:31 PM

In my original set up - with the drop block drag link - it could have gone back to OEM with a boxed in / cut out in the engine cross member...now with the rack and pinion - I think I will hit OEM components...
Jake