is it bad to leave the probe on fulltime.. or do you guys cap the port when not tuning..

would like to leave it on fulltime so that i can monitor but dont want to have to buy a sensor every so often..

btw.. whats the ideal temp..

 

The EGT gage is used to tune full throttle high RPM mixture.



It is not typical on a street machine. The gages are very quick moving and dificult to read. Only in a steady state situation can it be done. Like a long pull in 4th or 5th where there is a few seconds between shifts. This will be a mixture in the mid 12s. The slightly excessive fuel load will help keep things cooler and if you premix, will give you extra apex seal lubrication.



Ideal numbers for long engine life and nearly best power are between 1550 and 1600 degrees, measured 3" out from the port face.



EGT is also affected by timing, inlet air temperature and position of the probe. Should be 3" out and on the outside of any curve in the header.



In any situation other than full throttle/ full load the EGT gage is of no value at all.



Use a heated (three wire) oxygen sensor rather than the EGT.



Lynn E. Hanover

 

I have them running all the time on my street machine. ~2" from my engine flange. Also can be useful with cruise timing and for correcting large injector imbalances. IMO should be used in conjunction with a WBO2.