Don Terrill’s Speed-Talk

Hello Mr. Stahl,
I had a question about the spacer plates that you put on to read EGT's before the headers. Do you need to place the probe in a certain place or area? Or are you just looking for a consistant readings. For instnace, if you had your engine on the dyno and had one reading with dyno headers, then had different readings at the racetrack with the race headers? Is that what your trying to get away from? That way with the spacer you can try different headers and get your EGT reading from the same source every time. Just trying to understand, I hope I was clear. Thanks for your time.
Shawn Ryon

I sent an email to Jere for as answer. Thanks, Don

Hello Shawn,
The objective is to place the thermocouples in exactly the
same place relative to the exhaust valve for each cylinder.
There are numerous issues that can change the EGT readings
from the dyno to the race track. First of all, optimum
jetting on the dyno is seldom optimum jetting on the race
track. Same for ign timing. The shorter the track, the
more the difference between dyno and race track. Fuel
distribution on the race track (tracks under 3/4 mile) will
never be the same as on the dyno. One of the advantages of
the thermocouples in a spacer plate, is the ability to
change headers on the dyno and not disturb the thermocouple
situation. Stahl Headers may have the only available dyno
data analysis software that allows you to see the EGT's
clearly due to the graphing method.