VVT ideas and testers

Testing and development of Megasquirt 3

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remsperso
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Re: VVT ideas and testers

Post by remsperso »

I answer myself ! :)
I read VVT settings in ms documentation, and I saw that VVT intake and exhaust tables have same shape, so I will try to use the intake table for one intake cam and the exhaust table for the other intake cam, as my engine does not have exhaust variable cams. :RTFM:
jsmcortina
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Re: VVT ideas and testers

Post by jsmcortina »

There's no need to use the exhaust table for an intake cam. The MS3 already supports controlling two intake cams.

James
I can repair or upgrade Megasquirts in UK. http://www.jamesmurrayengineering.co.uk

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remsperso
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Re: VVT ideas and testers

Post by remsperso »

The ms3 supports 2 intake cams in closed loop with 2 vvt oil solenoids and 2 vvt position sensors?
I didn't have find wiring for now, I will search again.
jsmcortina
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Re: VVT ideas and testers

Post by jsmcortina »

remsperso wrote:The ms3 supports 2 intake cams in closed loop with 2 vvt oil solenoids and 2 vvt position sensors?
I didn't have find wiring for now, I will search again.
Yes.

It supports up to four cams and up to eight solenoids with the latest dev code.

James
I can repair or upgrade Megasquirts in UK. http://www.jamesmurrayengineering.co.uk

My Success story: http://www.msextra.com/forums/viewtopic ... 04&t=34277
MSEXTRA documentation at: http://www.msextra.com/doc/index.html
New users, please read the "Forum Help Page".
CSXRT4
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Re: VVT ideas and testers

Post by CSXRT4 »

Im gearing up to do an MS3 setup on a Subaru flat-6 with dual AVCS (4 cam VVT). It uses 4 hall effect cam position sensors and 4 PWM oil control valves. Crank position is 36-2-2-2 and cam positions are 3 tooth. Ive been trying to research the msextra VVT system as much as possible but the information is still a bit thin. Is VVT control universal with its decoder/cam-position-detection or is it per platform? Is the Subaru AVCS (VVT) trigger system currently supported?

Also, I read in this thread that something is a bit odd with the exhaust cam control? If you put positive values in the exhaust cam relative angle table will this correspond to degrees retarded from rest position? The exhaust cams on the Subaru are normally fully advanced with no duty to the solenoid and as you apply duty they retard.


If the AVCS is not yet supported I could supply test data. We will be beginning the project shortly and should have it to a running state within the next couple months.


Here are some images of the Subaru system. The AVCS oil diagram is of the flat-4 with timing belt but is basically the same as the flat-6 although the latter has a timing chain.
crank trigger.jpg
cam trigger.jpg
Subaru-AVCS-system.gif
Matt Cramer
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Re: VVT ideas and testers

Post by Matt Cramer »

The main thing is making sure your crank / cam decoders support your tooth pattern. In the case of the Subaru AVCS pattern, the answer is yes.
Matt Cramer -1966 Dodge Dart slant six running on MS3X
CSXRT4
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Re: VVT ideas and testers

Post by CSXRT4 »

Is it supported for the 6cylinder EZ30/36 engines though? They have a different cam trigger pattern than the 4cylinder AFAIK.


Here is the 4cylinder AVCS cam trigger layout (compared to the 6cylinder I posted above).
EJ255_cam_position.jpg
phongshader
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Re: VVT ideas and testers

Post by phongshader »

CSXRT4 wrote:Im gearing up to do an MS3 setup on a Subaru flat-6 with dual AVCS (4 cam VVT).
Did you get your engine up and running?
MSII, V2.2, LC-1
Olds 215 v8 in a '59 Alfa Romeo Spider 2000
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MS3/3X, LC-1
Duratec 2.3, GSXR itb, Locost
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Website: http://www.lightningbugcars.com
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