EGT probe placement

[trib]

I have a vetterman exhaust system on an O360 engine. The probes are located 1 3/4" from the flange as this was the furthest I could get them without going below the slip joints and their mounting flanges. The next location would be almost 7" from the flange. The issue is that when leaning (carburated, the big pull) temps generally run in the 1450F range. I typically do the big pull and then enrich to about 1450F. I'm considering moving the probes to the 7" location, but hesitate due to the slower response time. My EMS is a vision microsystems 2000C and tops out at 1500F, which I can exceed during the leaning process.

Anybody else have the same issues with location? where did you end up placing your EGT probes?

[RV10inOz]

Tim,

Leave the probes where they are. For one they are there! The general rule of thumb is 2-4 inches, but the it really does not matter as long as they are the same for comparative purposes. Moving them will give lower numbers and might extend the probe life a little, but it is a small gain for a lotta pain.

There is no EGT limit, only for turbos which have a TIT limit and that is the impeller that is of interest.

As for your leaning process, that seems very sub-optimal to me. If peak EGT is around 1500 and you lean using a number of 1450 on the rich side, that is about the hardest on the engine you can get. At 13,000' it is not much of stress issue, but down low it does not make a lot of sense. It may at high powers be a very bad idea.