EGT probe placement
I just installed a JPInstruments EDM 700c...and love it..
on a RV-6 0-360 vetterman exhaust.
the book said 2 to 4 inches from the cylinder head....
but stressed all 4 equal distance for accurate readings
If you look all all 4 cylinders, the #1 cylinder has the quickest bend.
I didn't want the probe in the bend, possible affecting the readings on that cylinder, I'm almost sure I used 2 3/8 inches from the bottom of the exhaust flange....that would make about 2 5/8 to 2 3/4 from the cylinder head.
Like others said, stay away from the slip joints and make all the same distance down. Think ahead with the placement location around the pipe...as to not interfere with the plug wires, primer lines etc.
I routed my probe leads around to the inside of the intake tubes and mounted them with tywraps....neatly bundled. Maintain some amount of give in the mounting as the engine shakes, rattles and rolls and you want the probe wires to hang in there with it.
Also, I used a EPM firewall penetration
http://www.epm-avcorp.com/tubeseal.html
for the probe leads and engine ground wire for this install and Loved it...I highly recommend it, simple and clean, but not cheap. Also I purchased hardware store clear flexable tubing, 1/4 or 5/16 ID I think, and routed the 4 left wires and 4 right wires thru them from the firewall penetration to the point they split apart. this makes the routing and attaching easier and a cleaner looking job. IMHO
Bob Martin
Louisa, Virginia