w123 230-280 conversion
Discussion
Should be quite straight-forward... the W123 was offered with the 2.8 M110 engine as the range-topper, pretty sure it would be the same transmission so in theory it should drop in and bolt up nicely. I had a S-class with the 2.8 engine and it's my least favourite MB engine I've experienced- noisy and as thirsty as the V8's, good torque but 'tizzy' sounding. The 2.3 4-pot is a good match in the W123 imho.
The bodyshell is the same .
I'm not certain the gearbox is exactly the same (ratios) , diff may also be a different ratio and the propshaft may be shorter ; the M110 is heavier than the M102 so you may need to change the front springs to cope with the extra weight ; brakes may also be different . Even silly things like the speedometer will be different on a 280 from the one on a 230 ( turns ratio and max indicated speed will differ , plus in a W123 rev counter was standard on the 280 , optional on pre facelift 4 cyl models with a big clock fitted in its place - 4 cyl pulse rev counter also won't work on a 6 cyl engine ) - the deeper you get into it the more silly little things will be different . Cosmetic differences - Pre facelift 280 had different lights from the lesser models ( after facelift all models got 280 style lights ) , chrome vents in front of the windscreen instead of plastic , chrome trim below rear lights , different rear bumper , trim around the window apertures , bare paintwork on the lesser models ........ those are just things I've thought of in a few minutes . 280 exhaust system is different too ,....... oh - 280 runs 185/70 HR14 ( hard to get now ) lower models ran smaller tyres .
It would be easier to just sell the 230 and buy a 280 , but if you're attached to the car or it is special in some way then the best thing would be to get a complete donor car so you can swap all the componenents required .
The MB EPC will be your friend since it will tell you which componenets are the same and which differ . You can get access to it either by subscription , or as part of your membership of MBOC .
I'm not certain the gearbox is exactly the same (ratios) , diff may also be a different ratio and the propshaft may be shorter ; the M110 is heavier than the M102 so you may need to change the front springs to cope with the extra weight ; brakes may also be different . Even silly things like the speedometer will be different on a 280 from the one on a 230 ( turns ratio and max indicated speed will differ , plus in a W123 rev counter was standard on the 280 , optional on pre facelift 4 cyl models with a big clock fitted in its place - 4 cyl pulse rev counter also won't work on a 6 cyl engine ) - the deeper you get into it the more silly little things will be different . Cosmetic differences - Pre facelift 280 had different lights from the lesser models ( after facelift all models got 280 style lights ) , chrome vents in front of the windscreen instead of plastic , chrome trim below rear lights , different rear bumper , trim around the window apertures , bare paintwork on the lesser models ........ those are just things I've thought of in a few minutes . 280 exhaust system is different too ,....... oh - 280 runs 185/70 HR14 ( hard to get now ) lower models ran smaller tyres .
It would be easier to just sell the 230 and buy a 280 , but if you're attached to the car or it is special in some way then the best thing would be to get a complete donor car so you can swap all the componenents required .
The MB EPC will be your friend since it will tell you which componenets are the same and which differ . You can get access to it either by subscription , or as part of your membership of MBOC .
Edited by Pontoneer on Wednesday 11th April 19:59
Edited by Pontoneer on Wednesday 11th April 19:59
Edited by Pontoneer on Wednesday 11th April 20:04
thanks for the info fellas, i'm sorry but i don't think i've been very clear, i have a 230E saloon without a gear box (but great body and running gear), also a 280CE coup with a good engine and gear box (but a crap body). will the 280 coup gear box and engine fit the 230 saloon, sorry for the badly put question, and value your reply.
It should fit straight in , but you may have to swap over a few more bits than just the engine and box , as per my reply above . In particular front springs , diff , prop shaft ( not sure if coupe is shorter wheelbase than saloon and different length propshaft , length may also differ between 4 and 6 cyl cars ) , brakes , various electrical bits , speedo ........
You may need to get a new exhaust system since , from memory , the 230 has a single pipe system and a 280 has dual pipes all the way , saloon exhausts will differ from coupe ones .
the good news is that you have the complete other car , so should have everything you need apart from exhaust and possibly prop shaft .
You may need to get a new exhaust system since , from memory , the 230 has a single pipe system and a 280 has dual pipes all the way , saloon exhausts will differ from coupe ones .
the good news is that you have the complete other car , so should have everything you need apart from exhaust and possibly prop shaft .
chazola said:
Should be quite straight-forward... the W123 was offered with the 2.8 M110 engine as the range-topper, pretty sure it would be the same transmission so in theory it should drop in and bolt up nicely. I had a S-class with the 2.8 engine and it's my least favourite MB engine I've experienced- noisy and as thirsty as the V8's, good torque but 'tizzy' sounding. The 2.3 4-pot is a good match in the W123 imho.
I love the M110, real sporty character and in many ways a more bespoke effort than its successor - the M103. People talking about the cost-cutting in Mercs should take a look into engines as well as platforms.
Twin cam mercs rule!
i can only agree with what has been said above....i worked for mbuk in the early 80's and have a soft spot for the m110 engine....not overly powerful but smooth and long lived ( 400,000 miles +) if looked after....cam chains can get a bit loose on high milage units ....camshafts can wear if oil is not changed on a regular basis ...cambox oil leaks...all minor stuff....ohh and No 6 plug is a git to get to and easy to cross especially in a 107 sl/slc.....but overall a far superior lump to the poxy M102 you are planning to replace...go for it.
Steve
Steve
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