M90 motronic rotor adapter

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wattsmonkey
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M90 motronic rotor adapter

Post by wattsmonkey »

Hi chaps,

If I wanted to run an M90 on Motronic, is this the adapter I need? I know I'll need a different upper timing chain cover and rocker cover too - but this is the part I'm most interested in.

Many thanks,

Rob
motronic rotor adapter.JPG
motronic rotor adapter.JPG (63.01 KiB) Viewed 1283 times
motronic rotor adapter 1.JPG
motronic rotor adapter 1.JPG (59.27 KiB) Viewed 1283 times
"Most of it necessary; all of it enjoyable." LJKS
'84 635CSi, dogleg...itbs and supercharger????? Eaton Mess
marc79euro645
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Joined: Tue Feb 11, 2020 12:31 am
Location: pensacola

Re: M90 motronic rotor adapter

Post by marc79euro645 »

Yeah, that looks like a motronic rotor mount. I'm not sure it's the right one. Early cams have a slot on the front to drive the dizzy. I think you'll need an motronic cam to interface with the rotor bracket you've shown in pics.
wattsmonkey
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Posts: 1649
Joined: Mon Jul 16, 2007 2:58 pm
Location: Cheltenham, U.K.

Re: M90 motronic rotor adapter

Post by wattsmonkey »

Thank you, I suspected it might be a little more involved! I'm told the profile of the B35 cam is very similar to the Hartge one suitable for the M90, so it might work out okay in any case.
"Most of it necessary; all of it enjoyable." LJKS
'84 635CSi, dogleg...itbs and supercharger????? Eaton Mess
marc79euro645
Posts: 56
Joined: Tue Feb 11, 2020 12:31 am
Location: pensacola

Re: M90 motronic rotor adapter

Post by marc79euro645 »

Personally, I prefer the early dizzy. It makes it easy to change timing and can be recurved, with lighter springs. I don't know if it could work with motronics though.
wattsmonkey
Platinum Member
Platinum Member
Posts: 1649
Joined: Mon Jul 16, 2007 2:58 pm
Location: Cheltenham, U.K.

Re: M90 motronic rotor adapter

Post by wattsmonkey »

Thank you, you've got me thinking now!

Cheers,

Rob
"Most of it necessary; all of it enjoyable." LJKS
'84 635CSi, dogleg...itbs and supercharger????? Eaton Mess
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