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Old 03 March 2000, 01:13 PM
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Blow Dog
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Hi all,
I once heard from someone that the colour of your backbox outlet tells you a lot about the state of the engine and how it is running. I am a little concerned with mine as I have been told gold is a good sign. Mine is almost black inside and very dark outside.
What does all this mean? I have a full scoobysport system, decat and running a non-re-circulatory dump valve. I also have noticed that my fuel consumption has gone down the shi££er recently and i am getting about 180 miles to the tank on a UK97 car.

All advice appreciated,
Cem
Old 03 March 2000, 02:09 PM
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Andrew Dixon
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Never heard that one.

It's normal for the exhaust to get very black inside. The Impreza tends to run rich, and deposits a lot of sooty type stuff in the exhaust. (And I don't mean little yellow hand puppets).

The outside of my Scoobysport 'box is just kind of metal coloured ... I usually end up polishing the tailpipe with metal polish once in a while, brings it up with a lovely mirror finish!

As for the fuel consumption ... anything to do with the fact that the car now sounds so fantastic when you put your foot down?

Andrew
Old 03 March 2000, 07:30 PM
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sunilp
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Cool

Cem,

1) You'll be hard pushed to get a Scooby to run a gold exhaust. They all run rich and thats the best way.

2) Polish the outside with Autosol...luckily for you that comes in a BLACK & GOLD TUBE....(best of both worlds eh!)

Sunil
Old 03 March 2000, 08:06 PM
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pat
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Sunil,

I could get a golden finish on my exhaust after a long run... my usual up to Edinburgh (about 420-450 miles) would leave the exhaust with a nice golden colour. Anything shorter and it goes black again. I guess these only run stoich (if at all) under little or no load.

Cheers,

Pat.
Old 03 March 2000, 09:39 PM
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Ian Cook
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It may be the dump valve making it run extra rich, that may explain why you have lost out on fuel consumption.
Old 06 March 2000, 07:42 PM
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sunilp
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Wink

Pat,

It had to be you didnt it

So i'll rephrase that Cem,..."Apart from Pats car, you'll be hard pushed......"

Sunil
Old 06 March 2000, 10:17 PM
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pwebb
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cem - check my thread at:
Old 07 March 2000, 07:21 PM
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pat
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Sunil,

It is quite odd, I agree. OK, my Link gave me a wonderful golden finish to my tailpipe on Sunday. It might also explain why I was able to stay out for so long without refuelling :-) But the really odd thing was that I could get a golden colour with the Subaru ECU. It's obviously an STi version, but it was remarkably fuel efficient; I got over 30MPG when taking it easy!!!

On the whole it should run a bit on the rich side... about one percent CO per thousand RPM for the best power / reliability. Now I just need to put this into practice! :-) :-)

Cheers,

Pat.
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