Re: 89.5 10vt [200]

[Mann Law <mannlaw@indy.net>]

	Scott, sometimes I have a hard time understanding your posts.  
Usually, I find some of the most important information, in anything, is 
the stuff that gets dropped due to our penchant for using .... I will try 
to avoid ... and tell what I know [which ain't much] using full sentences.

	On the cam portion of your post.  Yes, I have it.  Yes, I know 
the difference.  *One* difference is the profile related to timing of the 
exhaust valve closure, relative to intake valve opening.  In the drag 
racing days we spoke in terms of "overlap", that being the amount of 
"time" the exhaust valves were open--while the intake valves were open.  
Depending on your purpose in building the motor, ie., what you were using 
the motor for, your desire for overlap increased or decreased.  The cam 
on the dual knock sensor motors was designed by Audi to go hand-in-glove 
with the acual purpose of the dual knock sensor motor itself, to-wit:  
Increase low-end response [some would say throttle response] with a 
reduction in turbo lag.  Lighter pistons, lighter flywheel, higher 
compression, slightly bigger compressor, reduction [to near zero] of 
overlap, on and on.  Bottom line to this motor [the dual knock sensor 
motor] was make it feel like something it was not---a small block V8.  
The cam in the dual knock sensor motor is ground so that an *improvement* 
is [was] made in overlap.  Specifically, the exhaust valves close at the 
same instant the intake valves open.  On vehicles [like yours, Scott] the 
exhaust valves are open for some period of time while the intake valves 
are also open.  Thus, on your car, some measure of performance is lost by 
the goodies coming in through the intake valve  being released through 
the exhaust valves--before the goodies have a chance to burn--thereby 
creating power.  If I am not mistaken, the overlap was "solved" so as to 
meet the intent of the design, that is, better low end response, better 
throttle response.  

	Do I get an "A" on the cam portion of the test?:)

	The second portion of your post was a bit more nebulous.  That 
is, the increased *risk* of computer box changes, turbo changes, etc.

	First, I very much understand that I am assuming the risk of 
anything done to my car.  Secondly, risk, and especially *increased risk* 
is so relative a term, or phrase, as to almost be meaningless.  You speak 
in terms of increasing the "kaboom" factor.  I assume you are talking 
about the risk of burning holes in the pistons, etc.  Correct?  If so, I 
will be the first to stand by this statement:  You technically increase 
the risk of some failures when you increase boost in a turbo motor.  Now, 
we probably aren't talking much of an increased risk if we are talking 
about a .00005% increase in boost--but I think you understand my point.  
That is why *many* hp seekers in expensive vehicles like Porsche---run 
stock levels of boost, but increase hp dramatically.  Extrude hone, valve 
work, head work, exhaust manifold [read header] changes, intercooler 
changes, stroking, boring, etc., are but some of the ways you can 
maintain relatively stock levels of boost while increasing hp, often 
times dramatically.  Frankly, unless we are going to talk a specific hp 
increase at a specific rpm range--increase hp means nothing to me.  
Torque is what I like [and yes, you do [can] increase torque by 
increasing boost].  But when we talk hp mods., let's talk specific rpm 
range hp changes, ok?  *If*, a person is looking for low-end performance 
gains [hp gains, torque gains, throttle response, etc.] then the RS2 that 
everyone is talking about is best kept on the shelf.  The lag it carries 
stock will have you putting my "little" turbo back on.  Simply bolting on 
some "new" turbo is not the answer for 99% of the people on this list who 
want more usable power for city driving, 1-2-3 gear driving, etc.  

	In short, I do understand the risk of increased boost, but I also 
understand that people are misled into thinking that an RS2 turbo tweek 
is going to make them see naked mermaids on their next trip to the 
7Eleven.  Won't happen.  Ever.  IMHO, you must address how you drive and 
where you drive.  If you want to put a car on the track at Daytona and 
run for 3 days, get a huge turbo, huge intercooler, etc., because it will 
increase power.  If you want to drive a quicker car to work, maybe play 
with a Mustang or 3 at the corner light----seek out the budda named 
"low-end power".  BTW, detonation is what we should fear, and it is 
called many things like "kaboom".  Scott, my fingers are tired, and my 
test is nearly written.  Why don't you explain to the good folks the 3 
best ways to avoid detonation.  Intake air density is where we begin....


Peace

Bruce