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OK guys, pay attention. I've been chatting with one of the engineers and here's what he had to say about using a stock MC style ISV:

On GPO 1 or 2, put a diode across your ISV, with the cathode to the
+12v side of the wiring, and
the anode to the GPO output.
a 1n4003 or 1n4004 should do the trick.

This will enhance the linearity by about 4/1 since the flyback from the
solenoid isnt lost to the zener clamp.

GPO 3 and 4 are to be connected to a solid state relay, not direct to
any solenoid.
There is no flyback protection on those chanels.

You cannot drive any coil-type relay with GPO3 and 4.
The flyback when the relay is turned off, will damage the drive
transistor.
 

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Jim,

Thanks, it makes sense.

Also would you mind to share the values you are using for the ISV table?

You can email me privately at [email protected] if you prefer.

Thanks,

Carlos.
 

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Jim, I thought I'd shared this information with you in the past, its also in more recent tuning manual releases, pulled from the latest:

Boost Control: Boost can be controlled by manually manipulating the pressure signal to the wastegate or by using an outside electronic boost controller. Currently the 034EFI ECU will control boost pressure to a wastegate via one of the GPO channels (General Purpose Output). Only a relay should be connected to GPO 3 or 4, any solenoid device should be run off the 8A GPO1 or 2 Channels (Damage will occur if this in not adhered). Many different strategies can be applied, but most will involve pulsing a frequency valve to bleed or modify the wastegate pressure signal. This can be mapped via a GPO using various parameters. NOTE: If the range of the frequency valve is very limited using the GPO output, insert a 50-100V, 3-5 amp Diode across the solenoid terminals to increase its effective range. The cathode should go to the Power side, the Anode going to the ground side (ECU output)
 

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Sweet, thanks Jim, I'll have to give this a try soon, the cold starting with no ISV isn't very much fun lately :p
 

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Nice Jim, glad its working nicely
 

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Oh yes, also, I was thinking that eventually we'll have to get you going on the IAC to free up one of your GPO channels, should you need it.
 
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