ecu mods--elec. boost controllers

[Pat Korach]

Ameer

  I have modified the Mac-7 to use in my 89 200 TQ and it worked fine.
 I would think you could modify the Mac-11 to use with the KH engine.
Therefore you would have a chipped KH engine.

Pat Korach
Kirkland, WA

Ameer Antar wrote:

> there's a lot of ecu mod talk. Mostly about cheap and dirty ways, not
> replacing the chip. Well, I've been thinking about it, b/c the ECU for the
> KH engine does not have a programmable chip, so a hack is the only option
> other than ECU/harness transplant. If the ecu is designed for 1.4 bar, I
> was thinking of regulating the boost pressure to the ecu. I want to be able
> to get .8 bar or so, but I don't want to change the way the engine operates
> below 1.4 bar. The other resistor or aquarium valve mods change the
> apparent pressure throughout the range. However, if you could
> electronically control a ecu leak valve, you could tell it to seal shut
> until 1.4 bar, then gradually divert excess boost beyond that point, until
> it reaches some set limit. The circuit would probably be just need a couple
> pressure sensors and an op-amp or 2. The only thing is finding a cheap air
> valve that can be controlled by an electric signal.
>
> To limit the boost pressure sent to the ecu, you could make the valve open
> slightly and adjust its position just as an aquarium valve, but by sending
> it a voltage. Or you could do it by opening and closing the valve at
> different duty cycles to achieve the right amount. The problem w/ this is
> the valve would prolly have to move very fast. The problem w/ the first
> method, is that I've never seen a solenoid valve which had variable
> opening...ie. it's either open or closed. I was thinking of using an old
> wastegate freq. valve, but I'm not sure how if it'd work, and my car
> doesn't even have one. How so those boost controllers like GRreddy or Apex
> products work? Do they use a variable valve or do they use a duty cycle on
> the valve? Wonder if the valve can be bought separately...I guess I could
> just buy a boost controller and replace the wg spring, but I'd rather come
> up w/ something myself if they're like $200. I've asked lot's of questions
> so I really appreciate any info you can send me.
>
> -ameer
> '84 5kT