Dear friends
I am just working on a project like these for a customer who owns a w113-230SL which received and engine and transmission transplant from a 560SL-88’
I am working on the engine control and communications with the original body harness.
While this is an interesting work which now is demanding lot of neurons and specialized man hours to solve a job that was not very well plan ahead.
These are my advises based on this actual experience
1. Take in mind the limitations of signal availability/translation on your classic car. This means the following.
On a modern drivetrain the speedometer is electronic and forms integral part of the drivetrain to inform different components of actual speed and adjustments that therefore will be made to the combustion control, the automatic transmission, etc.
A W111 or w113 lack of an electronic speedometer capable of converting the VR signal coming from transmisión into the appropriate square wave signal needed by those ECU’s that control engine and transmission
2. Tachometer. You should source one later w111 or w113 electric signal tacho that can use signal from coil negative terminal to display engine speed
3. Temperature gauge. You will have to built and hybrid unit to replace original w111 gas driven temp gauge
4. Oil pressure gauge. You will need to make a conversion to your gauge or find a good sampling point on the new engine to install a capilar tube to bring oil pressure to instrument cluster.
5. Full harness modification. The original w111 harness should be modified to increase the load that can pass through it.
6. Interconnection ports. The w111 harness should be heavily modified to provide new circuits needed to power the new engine / drivetrain. Apart from that, in order to be able to use original engine / transmission management harnesses the original harness from w111 has to be modified in such a way that provides necessary inter communication ports bringing all the signals needed from legacy systems.
Keeping all that in mind my advise is try to go for and engine swap that uses only these engine control technology:
Bosch k-jetronic. Any engine with these engine management technology is relatively easy to implement. KE-jetronic is a step up, and require more work.
Look for engines that have an hidraulic controlled transmission, and avoid ones that require an electrical speed signal, unless you plan to spend big bucks.
Best regards
L.peterssen
