ecu mods--elec. boost controllers

[Pat Korach]

I guess I did not expain it completely.  I have modified the Mac-7 to work
on my 89 200TQ MC engine only as far as the pinouts for the connector and no power
mods.  I would think you could modify the Mac-11's pinouts to work with
the KH engine.  I would assume the power mods you do to the Mac-11
would work to .  I have never done it this but I would think it would  work

Pat Korach
Kirkland, WA

Ameer Antar wrote:

> thing is though, a mod would be a lot easier and cheaper than an ecu
> replacement.  ECU's are at least $200 guaranteed, plus you need to have
> that one modified too, which actually doesn't sound that much better for
> the engine than just playing w/ the boost sensor voltages. In fact there
> are quite a few MAC 11 mods that just use resistors and reprogrammed boost
> fuel cutoff. If my ECU, is doing fine, I'd rather just work w/ what I have.
> I don't really feel like dealing w/ whether a new ECU would have extra
> sensors, plus that ECU is designed for an engine w/ a comp. ratio of 7.8
> vs. 8.3 for KH, and prolly 8.5:1 on my KH.
>
> You say you used the MAC 7, which is what I have for my KH. I was told this
> box can't be re-programmed. How did you modify this? Thanks again.
>
> -ameer
>
> At 08:06 PM 10/18/00, you wrote:
> >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