exhaust temp

[jsthnt@gmail.com]

I put a Pyro in about 1.5 inches above the turbo housing before I went hunting last weekend. I have never been around a pyro before, so what I encountered confussed me a little. I added the turbo, but have not changed the timming yet ( I have not found the information to do it yet).
It was very windy here in Nebraska last weekend and it was a head wind both going and comming. I drove from Grand Island to Brady, Ne. close to North Platte. Then I dropped down into the hills. I don't know how many of you have been on that stretch of road, but it is flat.
On the way out I had a fifty fifty mix of wo and diesel. I ran about 1125. At some point the temp droped to 1080 and the speed went up by 10mph.
On the way home I put in about 20 gallons of diesel in. The temp went up to 1200. The speed was all over the place, I tryed to hold it about 1150.
Why does the temp vary so much?
What is a safe temp reading for a pyro set up before the turbo?
If I advance the timming will it help?
Thanks

 

[SCSG-G4]

Pyro before turbo should not go over 1200 degrees. It's actually hotter in the cylinder and the pistons are made of aluminum - they start to melt when the pyro gets to 1200. Does terrible things to compression and the engine in general.

 

[Rubenk]

The exhaust temp is a direct measure of the air coming out of the engine at that exact moment. You can coast and watch the temp fall nearly immediately. They are not going to show temp like a normal engine temperature guage, as they have such a huge mass of material and coolant to heat/cool, so the temp wont change very quickly.

 

[cyruscat]

Adjust Fuel first

If you drilled/tapped and mounted your probe above the turbo in the cast iron manifold you are in the right spot.
You say you added the turbo so the adjustment you want to make is to the fuel rate/amount. I don't believe timing adjustment is needed. There is a sticky with pictures at top of the catagory on how to do this.

From the temps you list your getting a little too much fuel. Do you get thick black smoke from the exhaust pipe when under a load (hill climbing)? That indicates lots of fuel which means more power but also more heat!

I have mine adjusted so it cruises at 900F, under load it climbs to 1100F which is OK for short periods.

Now your MPH reading could be a speedo cable in need of lube or bad speedo.

The best fuel adjustment for me was to decide on how much WMO or Diesel you will normally run and adjust for that. This will give the most uniform performance.

Study the guides on here and don't be afraid to tinker around with the fuel rate.

Half the fun of owning a Deuce is tinkering with it

 

[jsthnt@gmail.com]

Before I put the turbo on there was so much smoke that this seems like no smoke at all.
The speed is from a gps.
I live in Nebraska, so I do not have the opertunity to run wmo all winter long.
I am about due for an oil change would this make the engine work harder?
I thought that I read that without a turbo you could not run to hot, is this true?
If the compression is starting to go will you have the same heat and less speed?
If the air filter is getting plugged will that affect the temp?
Thanks

 

[RedbeardTheZombieHunter]

I seem to recall when Ian was playing with The General, there being a substantial amount of smoke out the stack so someone might have turned it up a bit. If it hasn't been adjusted since then, you might wanna turn it down just a smidge. The farther you keep the EGT under 1000, the better! over-temping of the combustion chambers causes damage that is cumulative. You may get away with it for a year and a half before your turbo lets out a bitter death-scream and stops spinnin. (as another SS member sadly discovered) Or you could be melting bits of a piston top away and if it goes through, BANG! about $2Gs worth of damage. (scary) If you turn your fuel down until your EGT never goes over 1000, and typically peaks in the 850 to 950 range, you're golden. Remember, it wasn't made to go fast!

 

[turbovr6jetta]

Pyro before turbo should not go over 1200 degrees. It's actually hotter in the cylinder and the pistons are made of aluminum - they start to melt when the pyro gets to 1200. Does terrible things to compression and the engine in general.

I don't quite agree with this. The temp in the exhaust manifold is quite often higher than inside the cylinder. The gases are still burning was they leave the cylinder into the manifold. However I do agree that cooler is better. My truck also seems to run hotter that I would like. The FDC is bypassed and its got a muffler. And when I'm rocking up an incline at 52 mph she will get up to about 1200 and she likes to run 1000 to 1100 crusing along... I will have to do some tinkering.

 

[kipman]

Sounds like your fuel is already turned up. you should see about 1/4 inch of threads on the go fast screw.

 

[barefootin]

Sounds like your fuel is already turned up. you should see about 1/4 inch of threads on the go fast screw.

Mine is all but .400" of exposed threads on the go fast screw and produces NO smoke and EGT's rarely break 1000. That's how it was when I cut the safety wire off to take a peak. She's got great power though, so I don't mess with it.