Curious Cabriolet Engine Transplant Question
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2018 GLE350, 2014 G550, 2000 SL500, 1980 TR8, 1995 E320 Cabriolet
Curious Cabriolet Engine Transplant Question
I was just curious . . . has anyone ever transplanted the V8 from the 400e/e400, e500/500e or early R129 (same V8 as the e500, I believe) into a Cabriolet? Is this even possible or is the engine bay bigger on these cars? It seems to me that since these engines were all used in the W124 chassis, the necessary MB goodies (and potential donor cars) would be available to do it. It also seems like the resulting car would be absolutely smashing.
Just curious,
- FD
Just curious,
- FD
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300TE / 300E / 300CE
FD,
Here are a few examples for coupe chassis conversion. As with all conversions, wiring adaption or transfer is the larger task. Physically the V8 firewall and crossmember must be welded in. There are some conversions for the sedan...somewhere but not generally worth the effort because it's already available. Coupes, wagons, and the Cab conversions would be unique. I would be concerned at the structure of the Cabriolet chassis to handle the added HP. It has been reinforced but to what extent, only MB engineers at the time would know...
4.2L in coupe
5.7L in coupe
Here are a few examples for coupe chassis conversion. As with all conversions, wiring adaption or transfer is the larger task. Physically the V8 firewall and crossmember must be welded in. There are some conversions for the sedan...somewhere but not generally worth the effort because it's already available. Coupes, wagons, and the Cab conversions would be unique. I would be concerned at the structure of the Cabriolet chassis to handle the added HP. It has been reinforced but to what extent, only MB engineers at the time would know...
4.2L in coupe
5.7L in coupe
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From: New Zealand
1996 E320 Sportline Cabriolet x 2
Thread Starter
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From: Massachusetts
2018 GLE350, 2014 G550, 2000 SL500, 1980 TR8, 1995 E320 Cabriolet
Thanks everyone . . . not as straightforward as one might like. I agree about the Cab chassis not having the chutzpah to handle a V8. But a V8 wagon, now there's a sleeper. 
Thread Starter
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From: Massachusetts
2018 GLE350, 2014 G550, 2000 SL500, 1980 TR8, 1995 E320 Cabriolet
What about a C36 engine?
What's involved in putting a C36 engine into a '95 Cabriolet? The mechanicals look fairly bolt-in but I wonder about engine management, transmission control, ASR, etc. I know that '96 and later cars were OBDII which would add a big extra layer of complexity. Could the engine management system (ECU) from the original M104 engine?
Thanks,
- FD
Thanks,
- FD
Last edited by Floobydust; Sep 30, 2010 at 11:10 PM. Reason: fixed typo
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From: Massachusetts
2018 GLE350, 2014 G550, 2000 SL500, 1980 TR8, 1995 E320 Cabriolet
Okay . . . at the risk of reprising a well discussed topic, I wanted to bring up some questions about a C36 transplant again.
I am thinking about installing just a 1995 C36 long block in my 1995 HFM M104 e320 Cabrio (I have to address the head gasket issue at some point - why not do it on a long block first). For now, I would use the existing ancillaries, ECU, harness, exhaust, trans, etc. From what I've been able to glean from various forums, the long block should just bolt in. Just the increase in displacement (3.6/3.2 = ~12%) should provide some additional power. The question is - would the existing hardware and ECU run okay with the C36 long block? Has anyone done this? I have not been to find this specific example anywhere.
At the moment, I'm not trying to achieve the original AMG HP output specification. I just want to have the mechanicals in place so I can "play" the ECU later. Any thoughts? RBYCC? Others?
Thanks in advance,
- FD
I am thinking about installing just a 1995 C36 long block in my 1995 HFM M104 e320 Cabrio (I have to address the head gasket issue at some point - why not do it on a long block first). For now, I would use the existing ancillaries, ECU, harness, exhaust, trans, etc. From what I've been able to glean from various forums, the long block should just bolt in. Just the increase in displacement (3.6/3.2 = ~12%) should provide some additional power. The question is - would the existing hardware and ECU run okay with the C36 long block? Has anyone done this? I have not been to find this specific example anywhere.
At the moment, I'm not trying to achieve the original AMG HP output specification. I just want to have the mechanicals in place so I can "play" the ECU later. Any thoughts? RBYCC? Others?
Thanks in advance,
- FD
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From: Kirkland, WA
500E Signal Rot
You can easily do a complete C36 motor swap, not just the long block. The biggest issue you would have to deal with is the ASR. If you cab has ASR, then its a mute point. If not, you would need to use the TB from your 3.2l M104 and transplant it to the C36 motor. You can also use your existing wire harness on the C36 motor.
The ECU is a bit more tricky, as its designed to be used on a car with ASR. I know you can use the C36 ecu, I just don't know exactly what needs to be done to it. You can also use your stock ECU on the C36 motor and it will run just fine. The A/F may not be up to par with the C36 motor though. If it were my car, I would either use the C36 ecu or use the stock ecu and add a piggy back ecu to it. You want something you can tune while on the dyno (you would also want a wide band O2 sensor). I used a Unichip piggy back ecu on my CLK and it provided all the adjustability I needed to tune the car.
I will make an inquiry about the C36 ecu for you. A friend of mine recently installed a C36 motor in his 190e, so he is probably the closest thing to an expert on this type of swap.
The ECU is a bit more tricky, as its designed to be used on a car with ASR. I know you can use the C36 ecu, I just don't know exactly what needs to be done to it. You can also use your stock ECU on the C36 motor and it will run just fine. The A/F may not be up to par with the C36 motor though. If it were my car, I would either use the C36 ecu or use the stock ecu and add a piggy back ecu to it. You want something you can tune while on the dyno (you would also want a wide band O2 sensor). I used a Unichip piggy back ecu on my CLK and it provided all the adjustability I needed to tune the car.
I will make an inquiry about the C36 ecu for you. A friend of mine recently installed a C36 motor in his 190e, so he is probably the closest thing to an expert on this type of swap.
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Thread Starter
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From: Massachusetts
2018 GLE350, 2014 G550, 2000 SL500, 1980 TR8, 1995 E320 Cabriolet
2PHAST -
Thank you for your post! It is very helpful. My car is an ASR car which, as you say, should simplify a 95 to 95 transplant. The ECU is the issue. There seem to be four options - have a re-mapped EPROM burnt for the existing ECU (There is a company in the UK that claims they can do this), use a piggyback system of some kind, find the very rare UK E36 ECU, or integrate the '95 C36 ECU. My thinking is that it would be easier to work with the existing ECU, but that may not turn out to be the case. I would appreciate knowing what you find out about the C36 ECU integration. But until I get there, I want to be able to drive/use the car with the C36 hardware in it. It sounds like that may be possible.
Thank you again,
- FD
Thank you for your post! It is very helpful. My car is an ASR car which, as you say, should simplify a 95 to 95 transplant. The ECU is the issue. There seem to be four options - have a re-mapped EPROM burnt for the existing ECU (There is a company in the UK that claims they can do this), use a piggyback system of some kind, find the very rare UK E36 ECU, or integrate the '95 C36 ECU. My thinking is that it would be easier to work with the existing ECU, but that may not turn out to be the case. I would appreciate knowing what you find out about the C36 ECU integration. But until I get there, I want to be able to drive/use the car with the C36 hardware in it. It sounds like that may be possible.
Thank you again,
- FD
MBWorld Fanatic!
Joined: Nov 2001
Posts: 1,213
Likes: 5
From: Kirkland, WA
500E Signal Rot
2PHAST -
Thank you for your post! It is very helpful. My car is an ASR car which, as you say, should simplify a 95 to 95 transplant. The ECU is the issue. There seem to be four options - have a re-mapped EPROM burnt for the existing ECU (There is a company in the UK that claims they can do this), use a piggyback system of some kind, find the very rare UK E36 ECU, or integrate the '95 C36 ECU. My thinking is that it would be easier to work with the existing ECU, but that may not turn out to be the case. I would appreciate knowing what you find out about the C36 ECU integration. But until I get there, I want to be able to drive/use the car with the C36 hardware in it. It sounds like that may be possible.
Thank you again,
- FD
Thank you for your post! It is very helpful. My car is an ASR car which, as you say, should simplify a 95 to 95 transplant. The ECU is the issue. There seem to be four options - have a re-mapped EPROM burnt for the existing ECU (There is a company in the UK that claims they can do this), use a piggyback system of some kind, find the very rare UK E36 ECU, or integrate the '95 C36 ECU. My thinking is that it would be easier to work with the existing ECU, but that may not turn out to be the case. I would appreciate knowing what you find out about the C36 ECU integration. But until I get there, I want to be able to drive/use the car with the C36 hardware in it. It sounds like that may be possible.
Thank you again,
- FD
I will still inquire with my friend and see if he has anything to input.
