Re:more boost

["Graydon D. Stuckey" <graydon@apollo.gmi.edu>]

On Tue, 14 May 1996, Peter Wales wrote:

> Wow, you guys love to pick a fight!!!! So all those experts who know better
> than me lets see the correct way to do it posted on the list.

No kidding.  Hopefully these responses are good natured.  I think so 
based on the mature attitude displayed in other contexts.  :-)

> For all the others, remember that the boost sensor will only measure 15 PSI.

Agreed.  From what I have heard, the stock boost sensor is only accurate 
up to 2 bars (~15 psi), ans anything over that will simply be read as 2 bar.

> If you remove the boost limit, you will remove the overboost protection. The
> dynamic impedance of a zener diode (hands up everyone who understands that)

Seems to me I remember a little about it, but I certainly wouldn't admit 
it in EE-trained company:-)  Someone might think I know something!  
Perish the thought.

> sensor limit), so go ahead and remove the limit and the overboost
> protection. At least you know its gone and can make allowances for it.

This is a good philosophical point.  As long as you are intelligent 
enough to understand what you have done, and astute enough to recognize a 
dying engine, you should be able to live with a mega-boosted engine 
without too much worry.  I tihnk that anyone willing to perform this type 
of surgery on their car ought to be willing to replace that block some 
day anyway.

> Finally I would prefer to have no protection against a diaphragm split( the
> way you guys go on, one would think the roads are littered with dead Audis
> with split diaphragms) than risk detonation by advancing the ignition timing

Excellent point.  I have rarely seen or heard of a dead Audi turbo even in 
these ranks of crazies. (yes, Scott and Eric, I include you guys in this 
class:-)  There are exceptions, right Scott?

> under boost. If you are going to put a divider in there and then remap it,
> why the hell don't you just change the software to move the boost limit up?

Exactly what I have been thinking.  SO, where is the boost limit on that  
Hitachi chip?  hmmmmmmm, back to the drawing board...

Later,								
Graydon D. Stuckey								
graydon@apollo.gmi.edu								
Flint, Michigan   USA
'86 Audi 5000 CS Turbo Quattro, GDS Racing Stage II