Hello Rudeboy,
Yes, I do run considerable smaller head clearance on other 2.5 cc speed engines without problems - using FAI fuel.
ORIGINAL: Rudeboy
Why do you suggest such a wide squish clearance?
I recommend 0.35 mm head clearance for the MVVS 2.5 because staying on the conservative side is better using these MVVS engines (two piece crankcase). Though the gap is quite large for this size of engine there won’t occur problems with overheating. They run reliably and last long with a moderate set compression ratio. More than 26 thousand rpm in flight would not be appreciated anyway. Unfortunately the MVVS 2.5 intake timings are weird, so here are limitations.
Compared to their price these small MVVS engines (2.5 and 3.5 cc) offer great value for the buck. With only little effort you can make them scream - nice for reasonably priced speed planes.
With a fully cowled engine+pipe the Blizzard will be a lot faster!
Regards
slomo
P.S For very satisfying performance of 2.5 to 3.5 cc speed engines, meaning above 35 thousand rpm in-flight, you must use conical glow plugs.