EGT

[Mississippian]

I am installing an Exhaust gas Temperature gauge on my FL250. How far from the cylinder should the probe be installed?

[K-fab]

You want it right in the kernel of the flame which is usually about 2" or so off the exhaust port.

If you'll mount it in the head pipe, just past the flange it should be good.

[Mississippian]

What is the normal operating temperature range on the EGT for the FL250?

[Beruba]

I don't know about the FL250 but I have the kosso EGT on my 600 SDI ski doo. The temp when I hold a steady throttle is at 1300F. The ECU on those machine control fuel delivery according to RPM, TPS & exhaust temperature. Yes, aluminum does melt at 1220°F. However, the pistons/motor aren't at 1300° when the EGT is. That has to do with the heat transfer from the gas to the metal. As long as your cooling system is adequate, it sheds the heat fast enough that the gas is at 1300°, but the pistons/cylinders are much cooler.
If you really want to be safe keep it under 1200F. If you want to get every HP out of that engine 1300F should be the sweet spot. 1400=.
Again I am talking about my experience on a 600 SDI SKI DOO. Your machine is air cooled that could be different.

[makenzie71]

So long as you're under 1300*f and are seeing less than a 250* wave it should be fine...a lot of the smokers I've seen run best around the 1150*f area.

[bdkw1]

Carbed, stay under 1250 WOT. FI has a lot more control and can get away with higher numbers. With a carb, anything over 1250 is a hiccup away from sending half the dome out the exhaust port.........

[Beruba]

Mississippian I'm not sure how much knowledge you have on carb tuning. This is a good guide line http://www.keihincarbs.com/tips/gate.html

[Kuma]

I've always heard it should be about 8" from the piston, with a 2 smoke you will be pulling in cooler fuel mixture into the pipe which gets shoved back into the cylinder with the pressure wave.

[Beruba]

http://www.transcanimports.com/downl...ccessories.pdf
10" to 12" from the piston

[Mississippian]

Thanks Beruba. The link to the pdf is what I needed. It seems that everyone has an idea of how from the cylinder the probe should be placed. I used to race the FL250 in the late 80's. My son sent me the pic you see in my post. It was my racer that I ran at Dutton Speedway in Oklahoma.