84-86 and 84-87 motronic questions

[inaminit]

Hello- I have bought an 89 engine for a learning project this winter. When that phase is done- I will look for a roller for it. I understand that the 87-89 engines with G50 trans used a particular flywheel and sensor arrangement, and that the 84-86 engines with 915 trans used a different system. My questions are: can you plug the 89 engine to an 84-86 trans and clutch? Is the sensor different? Which DME to use, or does it matter? Thanks in advance!

[ischmitz]

The sensors and electrical connections are the same across all 3.2. The only difference is the idle speed. Later 3.2 have slighly higher idle speed and the intake need to be adjusted accordingly.

Ingo

[dhagood]

is there a flywheel difference between the G50 and 915 carreras?

[dshepp806]

INGO: "adjusted intake", meaning "idle"? (RPM)

Thanks!

BEST!

Doyle

[Flat6pac]

Once you pull the bell housing studs, the short G50 stud is right to put where the long one is for the 915. You need a flywheel, and clutch package, 3 short bell studs and everything is the same.
The brains are different but the harnesses are the same but the 89 will bolt right in and will run when properly installed.
Bruce

[Brando]

There are also differences in the DME...

[DRACO A5OG]

OEM chip setup is different but will still work. Only 2K vs 4K chip set up, 84 is soldered 85-86 are not. OEM 84-86 it will idle at 780 vs 880RPMs