pitts12driver
Registered User
San Francisco, CA
As some of you know, we had a devil of time trying to get the cylinder head temperatures below 400 with our O-375 and the the standard nose bowl. We did our best with baffles and it looked tight, but we were never able to lean the engine at all.
So, we bit the bullet, and built a new plenum and nose bowl. Today was the first test flight (apologies for the mismatched primer) but it was successful. Temps were down across the board by 30-40 degrees depending on scenario. Normal operations had the cylinders uniformly in the mid to high 300s. Success! We are likely to still add some louvers on the lower cowl but this is a major step forward! It took 3 months, but it was worth it.
I've enclosed some pictures of the plenum, the old "stock Piper" nose bowl, and the newly fabricated pieces.
Adam & Doug
So, we bit the bullet, and built a new plenum and nose bowl. Today was the first test flight (apologies for the mismatched primer) but it was successful. Temps were down across the board by 30-40 degrees depending on scenario. Normal operations had the cylinders uniformly in the mid to high 300s. Success! We are likely to still add some louvers on the lower cowl but this is a major step forward! It took 3 months, but it was worth it.
I've enclosed some pictures of the plenum, the old "stock Piper" nose bowl, and the newly fabricated pieces.
Adam & Doug