Re: TQC boosst level in bars

[steveb@newkla.kla.com (Steven Buchholz)]

HACKHEWMAIM
> 
> Stock, the computer overboost-shutoff point is .7 bar boost or around
> 11 psi of boost (i.e., 1.7 on the guage scale) at most rpms (lower
> trip points at low speeds, like [wildly guessing] 1.2 bar at 2000rpm;
> over about 2500 rpm or so it's one constant trip point of 1.7 bar). I
> think the "normal" turbo 5-banger of that vintage is 1.4 bar boost
> limits.
> 
> No, wait, I think it's 1.9 bar trip point? Damn, hafta go look at the
> chart again. What is that they say about the first thing to go ? ? ?
> 
CLIPSNIPSHEAR
> 
> 					-RDH
> 

Just happen to have a copy of the quattro Intro Service Training book here
(thanks again Dave!)  ... two points of reference.  There is a graph of max
boost vs. RPM that starts at ~1.233984 bar at 1000RPM, moving up through an
interestingly smooth S shape that touches ~1.75 bar @2K, and levels off at
1.9 bar from 2500RPM and above.  The table states that the max pressure is
approximate.  The other graph shows the expected range of boost pressure at
5500 RPM WOT given over temperature.  This graph looks linear, and shows a
valid range of 0.71-0.76 bar of boost at -20degC decreasing to a range of
0.64-0.69 bar of boost at 30degC.  This second chart would indicate that
a reading of 1.65-1.7 bar would be expected at WOT @ 5500RPM @ 20degC.  I 
didn't find anything that explicitly states what pressure will cause shut-
down, but since the expected reading is about 1.7 bar, I'll assume that 
they put some margin in and set it at 1.9 bar.

Steve Buchholz

BTW you gotta stop talking about boosst level in bars ... she might be 
seeing someone already, and then you'll be in *real* trouble!