>From: Steve Haehnichen <steve@vigra.com>
>
>What do you consider too hot?  I've heard everything from 850 to 950.
>I was peaking out at 920-930 at the trap.  Where's the real
>(short-term) danger zone start?

The answer has been staring you in the face for a while now- just look at
your GReddy EGT gauge, the red zone starts at.. 900 C! :)  Keep temps under
900C and you should be fine.  In general 870 and below is a safe zone, you
should only see beyond 870 if you go WOT to the top of 3rd or keep your
foot on it for a while in 4th.  Because the EGT does not react like a boost
gauge (it's slower), pay attention to the rate of climb.  If you are
climbing very quickly from 830 to 900, then chances are you running too
lean at whatever rev range you are in.

Regarding your question about damage from a few 920-930 peaks, damage is
unlikely.  Damage occurs from sustained high temperature, a brief spike
typically won't kill you.  Personally, I would rather run rich and lose a
little power in exchange for peace of mind.  Avoid going beyond 900.

>I thought fuel cut happens when the injectors hit 100%... if that's
>true, then what does the TMO mod do that improves the situation?

There is more than 1 type of fuel cut.  Spend some time on the TMO web page
for more information.  The bottom line is that the TMO fuel cut removal
will do the trick.

Re: Your questions on 550's vs. 720's

If you don't have a solve for fuel cut lined up (such as the TMO ECU) then
go with the 720's.  Otherwise, go with the 550's.  Personally I have run
both w/ a 16G and have noticed little difference between the two once my
AFC settings were changed to suit the injectors.  I have noticed no
difference in idle between the two injectors.
Drag racers should err on the side of the 550's since with race gas you
probably can't lean the 720's out enough with an AFC or a MASC that hasn't
been modified for them.  (Unless the MASC allows more than a 30%
adjustment).

>I am running the stock cat and downpipe.  I can't seem to get a good
>feel for what kind of limitation that is.
>Would a 2.5" downpipe and hi-flo cat help lower temps any?
>I don't want to run catless, just because I go to the street
>races and that's the one thing they really seem to nail your a$$ for.
>The last thing I need is an EPA ticket.

Until you change your downpipe and ace cat, you will never be close to
realizing the potential of your setup.  And yes, going with a freer flowing
setup may lower temps, in general reducing backpressure lowers temps.  I
recommend you go with either an RRE or RSR downpipe, the bigger the better,
2.5" - 2.75" since you are FWD.

While I would never break the law, if I was a guy who wanted to go fast and
was wondering why I had put a lot of money into my car and it wasn't
performing well..  I would absolutely go with a test pipe!  If such a
person was worried about a ticket they could remove the heat shields from a
cat and weld them around the test pipe, it would look just like a cat.
They could even buy a little straight-through racing muffler and weld the
shields around that, it would help compensate for the quieting effect that
the cat used to have on their exhaust.  They would find the difference in
performance to be quite noticeable.  Until they free up their exhaust they
have no right to complain that their car feels slow :)

Marc

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