Engine With Inj System Marelli Vs Bosch, How compatible?

My S1 XM has Magnei Marelli Injection system and I am considering an engine swap.
I have a French repair manual (and if I can decipher it with my poor French) that says that the engines (2l injection) with MM have a different number of theeth on the flywheel. Possible then also different apertures for the TDC sensor, meaning perhaps a new gearbox (casing)? What about the other sensor apertures?
Looks like it is best to swap the whole system over as well. Could be a tedious job then, am I right?


Michael

Hi Michael

You will have to swap the throttle housing as well and the air intake trunking, the ignition system is different as well i think, might be a right pain in the ass

Dean

Well, I expected something along these lines - yes, airflow meter, everything.

Michael

yep,

the MM system uses a MAP sensor & waster spark ignition coil setup, no dizzy.
the Bosch has a flap-type airflow meter, single output coil (can't recall re ignition amp/dizzy, but latter quite likely)

You may find the dash instruments (Tach) differ too, depending on how the ignition & injection ecu's drive things.

Can't comment on sensor differences/teeth as I've not looked in this detail.

Had the Bosch on the 2.0SEi auto, the MM on the later 2.0SEi manual, the Bosch was smoother, but the air-control valve on the MM didn't help things.

rgds
Dave

Which Bosch system is this by the way? my Bosch system has no air mass sensor, only air temperature, throttle potentiometer and the map sensor is built into the ECU with a small hose connecting it to the manifold, mine is the Mp5.1.1

Dean

Well, I found a potential spare engine in a neglected XM that more or less equals mine but has the BOSCH ssytem. Now I only need to find someone who can do me an engine transplant at a reasonable cost around here.

Michael

it'd be v3.something on the non-turbo, can't recall which variant now.
Has the big metal block style flap sensor for air-mass, not the hot-wire type.

rgds
Dave

My S 1.5 2.0 SEi had bosch motronic but no flap type AFM. My manual Prestige had the marelli system. Can't say I have seen many with the flap AFM, I think its on S1 auto cars only. (both the cars refered to were manuals)

The gearbox is it is manual will be no diffrernt. If I were doing this I wodul keep the MM system and swap the flywheel as the block, head and rest of the engine should be no differnt. Keep the MM inlet manifold

Stewart

This post has been edited by Zaphod on March 30, 2008 01:36 am