Measuring piston position.

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toalan
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Measuring piston position.

Post by toalan »

Hi,

I am looking to build something that is able to plot various engine metrics vs the position of the piston.

Is there some IC/system that is universal; works with all different types of Crank angle sensors and triggers? I need something that will interface with the various types of sensors and triggers and outputs something that is easily read by a microcontroller.

Regards,

Alan To
thebigmacd
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Re: Measuring piston position.

Post by thebigmacd »

You wish :D

We all wish, it would solve a lot of issues with supporting crank and cam triggers on standalone EMSs

The LM1815 is probably your best bet as far as flexibility goes, we are using two to read the sensors in a 6/7 subaru.
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Fred
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Re: Measuring piston position.

Post by Fred »

The max chip is better, it supports hall/binary inputs as well as sinusoidal ones.
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toalan
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Re: Measuring piston position.

Post by toalan »

what is the model #?
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Fred
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Re: Measuring piston position.

Post by Fred »

9924? You've got to realise though, that they are both just VR conditioners, the thing you're asking for is the holy grail and the reason we're all here working away at stuff in the first place.

Fred.
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toalan
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Re: Measuring piston position.

Post by toalan »

Thanks for the part #s, Fred and keith.

I really did not have hope that there was a simple drop solution for working with triggers. I can make do with something that handles the analog front end.

Suppose I select a specific ignition setup as a start, what kind of setup would that be? What kind of triggers are most popular.

I am tripping over my words as I do not really know the proper terms.

I believe that MS requires a trigger wheel with a missing tooth to indicate TDC and each tooth indicates the change in angle. Do stock cars utilize this type of setup? Does MS use another sensor to indicate cylinder 1?
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Fred
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Re: Measuring piston position.

Post by Fred »

Megasquirt is probably the most versatile system in that respect! MS2extra can handle 20 or so patterns IIRC. I intend FreeEMS to handle much more. But yes, various engines have missing tooth setups. BMW use 60-2 and fords use 36-1 and others use it also.

There are lots of popular ones, toyota 24+2 is popular, on toyotas :-) etc.

Fred.
DIYEFI.org - where Open Source means Open Source, and Free means Freedom
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n00bs, do NOT PM or email tech questions! Use the forum!
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