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Garage => Test Drive => Topic started by: Mergyver on 12 May 2019, 10:37 AM

Title: 74 SEL engine swap
Post by: Mergyver on 12 May 2019, 10:37 AM
Haas anyone ever had experience swapping a higher horsepower engine into an SE or SEL?

My 74 450SEL is running fine but I keep on thinking about swapping a GM LS engine in in such a way that I could maintain the stock frame mounts. I love the car but an extra 100HP would be fun every once in a while.

Thoughts?
Title: Re: 74 SEL engine swap
Post by: ptashek on 12 May 2019, 03:47 PM
Quote from: Mergyver on 12 May 2019, 10:37 AM
Haas anyone ever had experience swapping a higher horsepower engine into an SE or SEL?

My 74 450SEL is running fine but I keep on thinking about swapping a GM LS engine in in such a way that I could maintain the stock frame mounts. I love the car but an extra 100HP would be fun every once in a while.

Thoughts?

There's a workshop in Germany who put a V12 from a W140 600SEL into a 280S, and a V8 from a 560SEL into a S123, so anything is possible...
http://roesenclassics.de/mercedes-benz-w116-v12-600-se/
http://roesenclassics.de/mercedes-benz-w123-v8-560te/
Title: Re: 74 SEL engine swap
Post by: Pete49 on 12 May 2019, 11:47 PM
Why stuff up a classic? Sell it to an enthusiast and buy a car with a LS in it. Just my 2 bobs worth
Title: Re: 74 SEL engine swap
Post by: Scotty on 15 May 2019, 03:30 AM
I think that it's your  car - your rules, though, for me, if a swap were to occur on my W116 it would be the E55  AMG W211. I've seen it done on a W124 (I think) and was quite the project.  I'm sure however you could easily get loads more horsepower from a 450 without the cost and bother of a conversion. But either way keep the forum  up to date not only on the outcome but the decision process too. It's all interesting to some of us!
Best of luck
Title: Re: 74 SEL engine swap
Post by: robertd on 15 May 2019, 10:35 PM
Hi Mergyver
I swapped a 5lt all alloy motor from a 1981 500SEL into a 1976 450SE, I have attached the forum link.
it was back in June 2012.
lots of fun

https://forum.w116.org/auto-torque/500-se-donor-car/msg100616/#msg100616
Title: Re: 74 SEL engine swap
Post by: robertd on 15 May 2019, 10:39 PM
And here is the car that got the transplant

https://forum.w116.org/test-drive/snatched-from-the-jaws-of-the-crusher/msg101920/#msg101920
Title: Re: 74 SEL engine swap
Post by: Mergyver on 17 May 2019, 11:55 AM
Hey guys thanks for your responses. Sorry I have been absent for a few days. You guys threw out a couple of questions so let me hit those first.

I like the ride and most of all the looks of the car. However there is only so much you can do with a D-jet 450. I looked for modified heads and longer duration cams but couldn't find anything practical. I did see a reference to an AMG head from that time period but could not find anyone reproducing it or modifying heads. Then came the D-jet problem. Even if I could get ported heads and a larger cam I couldn't find a way to modify the D-Jet fuel mapping.

To Pete49's point I am looking for a way to transplant an engine without modifying the frame or frame mounts. In fact I would keep the old engine that way if someone wanted to restore it back to stock they could.

I like the way Scotty is thinking. I used to own a E55 and that was a great normally aspirated engine and trans combination. I don't want turbos to complicated. I would like well north of 300hp though. I think my E55 was rated around 340hp. So I was thinking about an E55 swap but I have not seen many of those cars around much less salvaged engines and ECM's from them.

So then I landed on the GM LS motors. I have modified and retuned them before for another car I own (2009 Pontiac G8). They are relatively cheap and easy to find in salvage yards. Modified heads and cams are cheap and plentiful, the ECM's can be completely remapped to produce torque and HP at what ever level you want. They are all aluminum and really light. Stock exhaust headers are cheap and compact. All in all they just seem like the way to go for a someone without unlimited resources.

I am also thinking a GM LS motor would open up a lot of choices around transmissions also. I am thinking the stock transmission is probably not capable of holding more than 300 HP.

So that is my thinking so far. I am going to continue to look into it. As always I love the insight I get from this forum so all comments are welcome.


Title: Re: 74 SEL engine swap
Post by: Eyeman on 17 May 2019, 07:30 PM
Why not a 6.9 engine?  For sure you'd want to find a euro version for the higher HP.