re. Stebro [was: 4kq Exhaust time]

[Ben Swann]

Hi Ken,

I'll try to address what you are saying below, and if I don't know the
answer, I'll say so.

Ben

On Tuesday, March 26, 2002 10:26 AM, auditude at get.net
[SMTP:auditude at get.net] wrote:
> Hi Ben,
>
> I hope this doesn't sound like I'm arguing, I'm just sharing my thoughts.
 They are
> based solely on surfing the net.  I haven't seen, driven, or heard a
Stebro system for
> myself.
>
> On 26 Mar 2002 at 8:39, Ben Swann wrote:
> >
> > There is a reason Stebro went with the 2.5 or so(forget exactly, but I
> > have the specs somewhere).  They tested larger diameters on the 5000
> > Turbo including 3".  They lost too much velocity in the system
> > resulting in drivability problems.  3" is way too much they concluded
> > unless the car would be driven wide open all the time.
>
> Isn't the stock 5kcstq exhaust somewhere very close to 2.5", except that
it is metric?
>
No the stock system is more like 2 3/8" less in many places where it is
crimped.  The stock system is not bad, but I doubt you'll improve on it by
just inserting freeflow mufflers.  I kind of like the design of the stock
system, but wanted some improvement, especially to coincide with other
enhancements.  Seat of the pants, it is hard to tell if I got any increased
power by just adding the Stebro(using original cat).  It sure does sound
nice.

> If that is true, then somebody like me might be able to save some money
if their
> pipes are in good condition, by only putting in a high flow cat and
replacing the
> mufflers, keeping the stock piping.
I can only say that the Stebro tubing is much bigger - put the stock beside
it and it looks puny in comparison.  I should have taken a picture - maybe
I did.
>
> I thought with a turbo, the less backpressure the better.  Keeping a
high-flow cat
> would be enough, even if there were no exhaust after it(?)  That's what I
thought,
> anyhow.  The turbo and high-flow cat might provide the backpressure
needed for off-
> boost response (in theory, of course).  I can't say I've tested any
systems besides
> the stock one. :-)
>
> > My observation is that the Stebro system including larger Cat will
> > provide soo much flow improvement over stock that you would now have
> > do develop a special downpipe and overcome other bottlenecks in the
> > system before having the need to go with a larger system.
>
> I hear (from here) the stock exhaust is pretty good, except for the cat.
>
> > For a system that just bolts on with no fitment problems, Stebro is a
> > winner and is worth the money.  This being said by someone who will
> > try to squeeze a penny every which way for it's blood.
>
> I think it's great that it's a bolt-on fitment with mandrel bends.  I've
never liked their
> style of muffler, as I understand it.  Isn't it just a hollow chamber
with pipes leading
> into and out of it.  Not even a perforated pipe going through the muffler
body like a
> Borla?  I'm not sure on this, but I thought I saw a cross-section of
their muffler and it
> was way simple, and struck me as not being so terrific for flow, since
the gases
> totally expand in the hollow area and then have to find their way back
out the pipe.
>
> I don't know where I got that idea about their mufflers.  You know, I
think it was from
> Stebro themselves.  At one point, I had email discussions with them
regarding having
> a system built that was of a larger diameter than their usual systems.  I
expressed
> concerns over the mufflers, and the diameter of the piping going through
it.  I wanted
> to know if they were going to have mufflers with larger diameter.

I dont know how they are constructed exactly, but I looked inside and there
is more than a hollow box.  I may be a perforated tube through the box.

>
> If I recall correctly, and I may as well email them to ask, they said
that the muffler
> bodies are hollow so there is no piping inside them.  I'm wondering about
this, so I
> think I will go ahead and email them.  If I get a reponse, I'll post the
results here.

It would be interesting to know.  How complicated does a muffler have to be
though.  Tear apart a stock muffler, if I recall it is a perforated tube
with glass packed around it.
>
> > p.s. the whole system was around $1k for 5ktq or around $700 for cat
> > back
>
> What does the whole system include that the cat-back doesn't?  They
provide high-
> flow cats?  That's cool

Right, they have a high flow cat 2.5" openings vs stock 2".  I felt I had
to go with this, as my nw bottleneck was obviously the cat.  I will let the
cat out of the bag today!
>
> Thanks,
>
> Ken
>