Best engine for a w123? - Page 2 - PeachParts Mercedes-Benz Forum

mercmad6.3 · #16 05-31-2006, 09:33 AM

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.

I have a W108 250SE here right now with the Australian inline Ford six in it,it's a 4.1 liter crossflow engine,vastly superior to the American six ,although it looks simlar,the block is wider and of course it has the crossflow head with the 351 cleveland combustion chamber design .
OK ,so what is involved in fittting a Merc V8 and trans into a w123? .
The tunnel is a bit tight with the 722.trans but it bolts in...so the engne bolts in too!,you can also buy a complete running 500-560 se/sel W126 for around a grand in the US ,and you get all the odds and ends to convert it over.the M116-m117 engines are not really heavy so the front springs of a diesel car will be OK.Just make sure you buy one that it running..there plenty of bargains out there so don't chase the first one you see.
Why not fit a US V8 or six???...the SUMP,it's in the wrong place on both Ford and Chev!!!,the hassle of cutting a sump and rerouting an oil pump etc aint worth the trouble and they're a lot heavier than the Merc engine in the earlier Pre GEN3 form.
The Ford Six in the car I have here has been modified to fit in the Merc and although the sump was modified extensivly the engine still sits a bit high and too far forward ,this has created a car which was a pig to drive and would understeer in all corners.You wil have the same trouble with the Chev etc in a merc.It's been done before and it's never been a popular swap.There are plenty of V8 W123's in Germany where it's a real hassle getting modified cars registeered and all have merc V8's.
The Performance of the Chev is'nt in the same realm as the Merc 560 either...

BobsterMan · #17 05-31-2006, 03:33 PM

Quote:

Originally Posted by mercmad6.3

...you can also buy a complete running 500-560 se/sel W126 for around a grand in the US ,and you get all the odds and ends to convert it over.the M116-m117 engines are not really heavy so the front springs of a diesel car will be OK. Just make sure you buy one that it running..there plenty of bargains out there so don't chase the first one you see.
Why not fit a US V8 or six???...the SUMP,it's in the wrong place on both Ford and Chev!!!...

Interesting info, MM, though I can't seem to get Merc engine weights, but if the number bolts in and the diesel springs perform, the question is answered. However I am led to the matter of the 500-560 SE/L available at that price... not to doubt it, but why so low. Even the 70's 280Cs are low for a pillarless hardtop... try to get a Chevelle or Nova 2d-ht for that money.

GM sump? Doesn't the early 70's v8 in that little two-door four seater jobbie from Chev and Pontiac have the right sump?

t walgamuth · #18 05-31-2006, 07:28 PM

i believe that the mb al v8 is lighter than the diesels. maybe 50#. all engine weights were posted in the last month or so so run a search and you will find it.

tom w

mbc43amg · #19 05-31-2006, 08:56 PM

Quote:

Originally Posted by t walgamuth

all engine weights were posted in the last month or so so run a search and you will find it.

I did a search for 'engine' and 'weigh' to get the most hits, posted in the last 6 months, but couldn't find it. What words do you suggest searching for? Thanx.

t walgamuth · #20 05-31-2006, 10:53 PM

did you try engine weight? (with a t)

good luck

tom w

mbc43amg · #21 05-31-2006, 11:05 PM

yup -- let me try again returning posts instead of threads however ...

edit... while I found some engine weights posted, I didn't find anywhere near 'all' MB engine weights. I was hoping to find a definitive answer for the difference in weight between the C43's 4.3L AMG engine and E55's 5.4L AMG engine; with the later having a much beefier crank and silica sleeve. Some say 50lb difference. I'm not so sure based on my running of 950lb/in springs up front after the engine swap, but with tires still easily bottoming out on the inside fender well.

StevenHamilton9 · #22 05-31-2006, 11:49 PM

best engine for a w123 is a 617 no doubt about it

t walgamuth · #23 06-01-2006, 08:51 AM

Quote:

Originally Posted by mbc43amg

yup -- let me try again returning posts instead of threads however ...

edit... while I found some engine weights posted, I didn't find anywhere near 'all' MB engine weights. I was hoping to find a definitive answer for the difference in weight between the C43's 4.3L AMG engine and E55's 5.4L AMG engine; with the later having a much beefier crank and silica sleeve. Some say 50lb difference. I'm not so sure based on my running of 950lb/in springs up front after the engine swap, but with tires still easily bottoming out on the inside fender well.

both engines are v8? same number of cams? same type of intake (al or plastic) either one have a super? if all major factors are the same, the difference in cranks would be minimal i would think. rods too. there is only so much room available so unless one has a major element made of titanium i would think the weight diff would be minumal. five pounds maybe at most.

tom w

mbc43amg · #24 06-01-2006, 10:40 AM

I'm confident it's more. Just the addition of the silica steel sleeves for the cylinder walls is close to 10 lbs I bet... The number I've both heard & read from multiple sources have all cited a weight difference of about 50lbs.

Anyway, my goal with looking for that post was to end all the mystery, guessing and supposition, and get the true, exact difference. Based on the posts I did find, I'm guessing when t walgamuth said 'all', he didn't exactly mean 'each & every MB engine ever' (i.e. M113.### wasn't covered)

BobsterMan · #25 06-01-2006, 11:58 AM

any dimensional sketches like the ones here... http://www.paceparts.com/index.asp?PageAction=Custom&ID=586

t walgamuth · #26 06-01-2006, 11:24 PM

Quote:

Originally Posted by mbc43amg

I'm confident it's more. Just the addition of the silica steel sleeves for the cylinder walls is close to 10 lbs I bet... The number I've both heard & read from multiple sources have all cited a weight difference of about 50lbs.

Anyway, my goal with looking for that post was to end all the mystery, guessing and supposition, and get the true, exact difference. Based on the posts I did find, I'm guessing when t walgamuth said 'all', he didn't exactly mean 'each & every MB engine ever' (i.e. M113.### wasn't covered)

drat! ... the dreaded imprecise statement!

hope you find the true facts. and report them here.

tom w

William73 · #27 06-02-2006, 12:20 AM

Today I found a M.B. with a DOHC straight six in it. Would this be a good engine to put in my W123? Does anyone know what displacement it has? I think it's a M110 engine but the car it's in looks older than mine. Maybe a W114. By the photos I have seen, I don't think it's a W116. By the info I have read, I don't see where a DOHC I6 was in anything but a W116. I'm confused.

t walgamuth · #28 06-02-2006, 09:22 AM

i sthis a duplicate post?

that would be a 280. also called the 110 engine. about 175 cu in. up to about 150 hp carbbed and up to 185 injected eruo spec. very nice durable engine. feels very good in a 123 car. i have a euro 280e euro with a five speed. it is a sweet combo.

tom w

ConnClark · #29 06-07-2006, 07:27 PM

Although your mileage will drop some I think this would be the best performance engine for a w123. Going from 3.0 liters to 56.0437589 liters should give the car a real kick in the pants.

You might have to modify the frame a little bit to get it to fit and handle the torque. You'll also have to find a differential to utilize the dual driveshafts.

William73 · #30 06-07-2006, 11:28 PM

I think I would have some fitment problems. One driveshaft per rear wheel would be cool. If someone gives me the engine, I'll put it in.