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Old 06-07-2010, 07:11 PM   #21 (permalink)
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The Van - '97 Mercury Villager gs
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I would be willing to blame a faulty boost gauge on that one.

IIRC EGT indicates temperature of the exhaust. I know, that's making it awful simplistic, lol. But for a high EGT, think lots of air and lot of fuel that is kept close to stoichiometric, whatever that would be for a diesel. One method some hotrodders use on the dragstrip with their diesels is turn up the fuel: it creates a ton of smoke, but that extra fuel lowers the EGT and keeps it in the happy place. Keep the engine from smoking and it requires a computer control to keep it close to the burn off the manifold temp.

Higher boost would raise the egt, especially if not accompanied with increased fuel injection. I'm no expert, so correct me if I'm wrong.

I do know higher EGTs spell death for a diesel engine, so it's best to avoid that scenario.

RIP Maxima 1997-2012

Originally Posted by jamesqf View Post
I think you missed the point I was trying to make, which is that it's not rational to do either speed or fuel economy mods for economic reasons. You do it as a form of recreation, for the fun and for the challenge.
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