[urq] Vacuum limiter : how to adjust ?

[Louis-Alain Richard]

OK then, I'll have to experiment !

I have two stock cars here, Eric's and mine. His is showing a very
un-sporty deceleration rate, that's why I wanted to play with this decel
valve.

In fact, I have another one here, from another car, and it is indeed
like a small blow-off valve. There is a spring in it that preloads a
piston, and this piston will retract under 16 in of Hg, thus opening a
passage between both sides of the throttle plate. The preload is
adjustable via the vacuum nipple. 

Now, what I need to know, is more preload of less preload will sharpen
the decel rate ?

If you don't remember, then I am sure someone on the list will !

Anybody ?

Louis-Alain



> -----Message d'origine-----
> De : Mike Fitton [mailto:rfitton at vt.edu]
> Envoyé : 20 mars, 2006 17:01
> À : Louis-Alain Richard
> Objet : Re: RE : [urq] Vacuum limiter
> 
> Oh man...it's been some time.  Haven't played with that one since high
> school.  I'm pretty sure it was a screw on the throttle body, but I
> played with just about every CIS screw on that car - and I still don't
> know the first thing about it.  But I definitely ran across some screw
> that my Haynes manual referred to as a Decel valve screw, and
> adjusting it definitely made the engine feel a little twitchier.
> 
> -Cheers!
> Mike
> 
> Louis-Alain Richard wrote:
> 
> >Hey Mike, can you elaborate a bit about this adjustment ?
> >Do you add (or release) preload to the internal spring ? By how much
> ?
> >
> >TIA
> >Louis-Alain