6,000 rpm?

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Amur73
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Joined: Tue May 05, 2020 2:03 pm
My E21(s): 78' 320 man

6,000 rpm?

Post by Amur73 »

How is M20 engine restricted to the 6,000 rpm?
What makes it stop revving?
What happens if you want to rev higher, for example up to 7,500 rpm?


Wilmo
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Re: 6,000 rpm?

Post by Wilmo »

Theoretically there is a spring in the rotor in the distributor. Because of the centripetal forces, a part of rotor get slung outwards and at some point creating a short circuit so no sparks are at the plug anymore.

But there are rotors without this spring that fit as well. In that case a cam follower or conrod will limit the rpm of the engine. Though less subtle.

The cam followers are designed to break first actually, to save the rest of the engine. It is said that these can do one time 8000rpm.
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Amur73
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Joined: Tue May 05, 2020 2:03 pm
My E21(s): 78' 320 man

Re: 6,000 rpm?

Post by Amur73 »

Thanks Wilmo!
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