Here is my attempt at warming up a -M1B cabin
First, I should say that I have done all the cabin sealing stuff on an RV7. Aileron boots, closed the spar holes, closed the corrugation holes in the baggage bulkhead and other minor stuff. The standard heater was OK (mild winter last year) but this winter I had two flights that were cold to the point of being dangerous. I was shivering when landing.
I designed and ordered a custom muff from Rick Robbins. The plan is to move my air inlet to the back of the oil cooler (because I run that some percent blocked all the time), through the custom muff on #4 and then across to the std muff and then on to the cabin.
Not tested yet. I will report here after I do.
First is the SCAT flange and bracket I fabbed for mounting on the Oil Cooler.
Here it is mounted with the SCAT slid in place.
SCAT going to the custom muff
This is a tight spot. The cowl is very close to the servo. I have the hose "nested" up in a hollow spot in the servo and zip tied in place. I will watch for scuff marks on the cowl here.
I flipped the standard muff upside down to make the cross tube connection better, but it forced the cabin tube inside the intake tubes. It's kinda' tight in there so I will probably get a new muff to get this SCAT tube back outside where it was.
The "per-plans" inlet hole on the #1 cylinder ramp has been blocked. It will be interesting to see if there are any noticable differences in CHTs with the closure of that 2" hole bypassing the cylinder fins and pressuring the post cylinder area.