Turbos and intercoolers / part II

Bob:

The interesting thing about the intercooler is that it does throw out the POH numbers if none were installed (as none were back then). The neat thing about the formulae I gave you is that they work WITH or without the intercooler. <g> FF is not at all usefull in determining HP output (which determines % HP) when ROP. The formula WILL work rich or lean. What the intercooler does do is allow for more HP when ROP or LOP. Why? Well, ROP, the air is cooler, the mass airflow is more, the HP is UP since the ONLY fa ctor ROP is mass air flow! LOP, the intercooler allows for more air molecules, allowing for the same FF to be further LOP and therefore at the same HP, cooler CHT's. It is not necessary to go through a bunch of Monkey Motions trying to figure out power settings... just use the formula I gave you. You can figure out ANY power setting sitting in your easy chair that way! You can make a chart of all MP/RPM settings which will determine % power without all that chart digging and trying to read all that really little print on the graphs! The older I get, the harder those charts are to read. Arrrgh.

We now appreciate that the real issue is peak internal cylinder pressures and we have come to appreciate further that controlling that is the key to engine durability. We also realize that the only effective method of controlling that is with the red knob since EGT is the surrogate for measuring ThetaPP.

PLEASE stop by our campsite on your way from the *corner*. We'll be under a trigear Twin Beech near the runway near Row 14 with a crowd of happy folks. I really hope we can meet.

Walter