Re: tricking the compooter

[orin@netcom.com (Orin Eman)]

> 
> In a message dated 96-11-13 09:24:51 EST, you write:
> 
> << PDQSHIP@aol.com wrote:
>  > The easiest way to do that would be with a 1.5 bar spring in the WG.....
>  the
>  > computer shuts off at 1.5-1.6 (depends on your pressure transducer)....
>  So
>  > the simplest thing would be to shim the spring or replace it with a
> stiffer
>  > one.... 
>  Well, I found it even easier to run positive manifold pressure, through a
> cheap
>  regulator, to the open nipple on the wastegate, helping hold it closed.
>  I didn't have to open the wastegate to screw around with springs, and it's
>  adjustable with a turn of the regulator. You can even run the line into
>  the cockpit for in-car adjustability.
>  I haven't changed anything in the computer, so I still hit the limit
>  at 12psi, and then back it off one notch.
>  Glenn
>  83 urq
>   >>
> And a great mod for the 83-84 cars....  Unfortunately on the 86>91 10vt cars
> the wastegate solenoid is at that port already, doing exactly what you are,
> only again, by computer set limits (+/- .1-.2bar)so to put the schrapnel
> knobben on might be more of a challenge...  I suppose you could tap it into
> the bottom hose (ala 20vturbo), but again, since you are limited to the
> computer boost preset, the spring is the easiest way to address boost....  A
> better mod on the later cars would be to address the programming of the DC in

It's even easier on the 86-91 10v.  I take the positive pressure input line
off the solenoid, run this into the pressure regulator then to the wastegate
upper nipple.  Plug the remaining hose to the solenoid (comes from the
turbo inlet).  Done.  Solenoid is no longer controlling the wastegate,
the pressure regulator is.

I haven't had much success reprogramming the duty cycle of the solenoid.
I do know where the desired boost tables are in the EPROM, but just
changing these isn't enough.

There is one more table to try playing with though...

Orin.