My Great Plains 2276CC with Revflow carb Cygnet cruise quite nice at 19.5inches of MP and 2850-2900 rpm. I believe about 45hp. 58x34 Ed Sterba Prop CHT ~305-315 on a 80 degree ambient. I climb to TPA at full power and back off to a cruise climb as needed to stay under 330f. The Cygnet flies great with two large souls and full fuel. I had a stud break after solo and made a precautionary landing without incident. On investigation I suspect the flaw was introduced when doable nutting the stud to install.. I decided to replace all studs with rolled 4130 studs and put new 040 heads from Mofoco. Standard valve size heads. Works great!
Please share more about your circuit that automatically switches in the bleed down electric system. Pictures of your fly wheel drive will always be appreciated.
Not all were matching form factor so no.Matt,
What spark plugs (brand/number) are you using in your engine?
Do you use all the same matching plugs for the magneto and the electronic ignition?
I have the boots removed also the axle tubes are removed with just the axles hanging in the wind but there is no snap ring like the newer swing arm tranny. Its a real head scratcher at this point and can find no reference on utube ?You have to remove those boots first. Those look like repair boots.
This is way off topic for HBA, but here goes....Here is a VW question. I have the very early style transaxle on my Trike and need to remove the axles but no snap ring in site. any body have knowlage on how to remove axles???
Not all were matching form factor so no.
Since I had a MAG on top I had Mofoco make those holes 14mm I use Autolite 2304 for about $8 each at O-Reilly Auto Spruce and Aircraft Parts. ;-)
I had an issue after installing the heads they require a 18mm reach and my "fine wire" aircraft plugs were only 12mm reach. Actually not a single shielded "14mm Aircraft" plug came in 18mm reach. Hummel Engine's Scott Casler was a fine man providing a solution and I never been a customer of his. Scott is a open book saving the day with the AUTOLITE 2304. Fred Keip of Sonerai fame confirmed the Autolite 2407 has 1/2" /12mm reach, owns a set and will install them on his magneto when the AC plugs reach the end of life.
I use 12mm NGK 3932 18mm reach below for the electronic ignition it s resistor plug with copper wires this combination attenuates radio noise well. Great Value at $2.69 a piece and O-Riley Spruce and Aircraft Parts.
MOFOCO built a fixture and puts the 12mm plugs in below on an angle to avoid the pushrods tubes. No issue with tool access like my previous head with 10mm plugs between the pushrod tubes. I had to make a trimmed down socket for those.
Based on my experience I would highly recommend you do business with Scott @Hummel and if buying heads from MOFOCO stick with the standard valve size on the 040A and plan to spend 1 hour with a hack saw and rat tail file set polishing any flash between the fins out. It was not much effort and every bit a flow you achieve will pay cooling dividends. No large valves are needed below 3500 RPM. Stock on 040A 40mm x 35.5mm stainless steel valves...better still order ala-cart have them duel plug the heads and use Stainless 35mmx32 valves.
My four "AC Fine wire" plus are available contact me offline if you care to make an offer. They are crazy expensive new. I recommend the new Autolites on a MAG great value