re. Stebro [was: 4kq Exhaust time]

[auditude at get.net]

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?

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 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.

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.

> 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.

Thanks,

Ken