efi Ignition Only Megasquirt Map Sensor Solex Carb

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I'm in the process of adding Megasquirt and the first stage is to add EDIS ignition http://www.bmw2002faq.com/topic/134019-73-fjord-with-megasquirt/page-2. I am unsure if i am able to use the vacuum take off from the Solex PDSI Carburettor to supply vacuum to the MAP sensor. There is only one take off on the solex and it is located just above the throttle butterfly. Or is there a more suitable point to get the vacuum from?

This wont be the final fuel solution, i will either go to 318i Manifold or maybe ITBs but will run it for a few months in this configuration so it needs to be a useable but not necessarily perfect solution.

[Rustpile]

I am running megajolt with map sensor. Take a look at my build: http://www.bmw2002faq.com/topic/139003-the-golfgelb-74/

 

You need to run the same thing, just the one vacuum point wont do.

[ar_kid]

As ever with Megasquirt it is configurable to your needs as long as you allow for it in the advance table but you may find the throttle plate vac signature isn't progressive enough to take advantage of Megajolts resolution. I suspect this is why most folks use plenum vacuum, ITB's are another story.

If your car is still running then tee in the map sensor, connect rpm signal and take some data logs, you'll be able to see how on/off the map signal is.

Rgrds

[mike472]

Connect your MAP vacuum line to a port on the manifold, not the throttled vacuum port on the carb. That's for a vacuum advance connection to a stock distributor.

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EDIT: Sorry Guys for wasting your time - i had another look this morning and found what i think is the perfect place to get manifold pressure from

Is this a good spot to supply the map sensor with vacuum info?

Edited December 30, 2013 by scanner

[Rustpile]

No, it is not. That is a throttled vacuum port, as mentioned in the post above. You have to tap holes in the manifold, and use a reservoir for the best result. As mentioned, take a look at my thread. This is the way to do it. Anything else might work to some degree, but you could just as well stick to the stock ignition then.

[allbim]

That goes straight into the manifold; right? In that case it's a good place to connect the MAP sensor.  No reservoir is needed since you're not trying to smooth-out any pulses as with ITB's.  I too used Megasquirt for a while, to run just the ignition.  It's a good way to get started and make sure the crank position sensing and triggering works.

Edited December 31, 2013 by allbim

[mike472]

That port is not throttled and is suitable for your MAP sensor

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Excellent, thanks guys, onwards and upwards!!