at least the fit has the extra heat from injection. I went through this same routine on a1781cc carbed engine. Best bet, lo and behold, was no grill block, even bigger air from the factory design. I went backwards for quite some time.
I ponder a real cheap solution, after breaking the element in my oven, and realizing it keeps working in pieces (cool) and making something safe and hot with a 20 dollar 400w invertor...it is so close to beng normal below single digits F, yet so far away...
Little engines suffer. Inlines do have it better than boxers...boxers throw it all away ..
the problem with winter is mileage, it absolutely has to take more in to get to thermal efficient, no getting out of this. I tried shallow localizing heat, and it is the same routine as you went through, best bet is to let it go. When it does reach the real wot, it is the larger one, and hangs on for the ride, and even shutting down intermittently hangs on better.
shallow localizing, cools it down faster, and is a waste of time, and hot oil and bearings and gaskets and...
