What is a pyrometer?

[filter]

What does it do?

[CDave]

Measures heat.

Usually Exhaust gas temp. Lean air/fuel mixtures run hotter, Rich air/fuel mixtures run cooler. Stoichiometric is the ideal air/fuel mixture/middle ground on normal rich burn engines.

I forget what ratio that, Stoichiometric, is and I'm too lazy to get out my Cat 3600G book.

Edit: I looked it up it's 14.7:1

[filter]

So I presume you have this meter hooked up to your motor while running or when testing. Is there something to use to monitor constantly the performance of the motor besides temp?

[Techno]

Most of the gauges are for performance and protection. All or only some maybe on the dash.
The 2 most important are the stop watch for the 1/4 mile people, and the GPS or radar speedometer for the top end people.

All the rest are used with other gauges usually. One by itself isn't as good as several items compared to each other.

EGT- The Exhaust gas temp, is for pushing or tuning but is compared to the pistons to actually find out if its running too rich or lean. On the fly look into the cylinder. Also tells you of something going wrong, if it is wrong its too late.
Draggers run lean for quick out of the hole and mid range acceleration. Lakers don't want this lean mid rpm spot.
1 or 2 gauges. For one bank or both cylinder banks.

The water temp and pressure are also performance as well as protection, Jack the engine up- but you need the cooling too.
Head temp is nice too. The higher the OB goes the better, as long as its getting cooled and still handles well.

Fuel pressure- Important on EFI so you know of a problem now rather than later. Lose pressure and you lose the engine. Anytime you run lean you run hot. If its a fuel pressure problem you'll change everything under the moon looking unless you check the this gauge. If its low then you just narrowed the search.

Tach so you know if what you did/ doing is the right/wrong direction. Tells if there is anything left to go for and is an hour rebuild indicator. The faster you spin it the quicker it wears.
Used with speedometer to calculate the prop slip. Also some engines can't be spun above a certain critical speed.

Fuel gauge- tells you to work some more OT to buy more fuel. Also indicates when to try for the fastest run when the tank is low and light.

Voltmeter- tells you why your anemic 19 amp charging system 260 isn't going to start. EFIs need 12 volts for the brain but can go a wee lower. With a fuel pump and electronic ignition doesn't leave much for the 600 watt stereo. Idling is going to suck the battery dry.


The most important gauge though are your cheek muscles. Depending on how much they hurt from smiling is the best indicator for optimum performance. The other set for how long you sat in the boat using it.

[filter]

I can put on my 300xp to tell me how the mix is. I got some bad gas and steamed my 2.4. Maybe if I had somekind of sensor I could Have caught it before it bent a rod and shoved it through the wall of the motor.

[Techno]

I'm guessing an EGT would have started to run higher temps but whether you would see it in time or it would register in time, I don't know.