I'm using a OS.32sx/Macs pipe combo for a 3 lb. Diamond Dust and I'm expecting speeds of 120mph.
If I'm not mistaken, a lot of guys use the 32 for a Model Tech BF 109 and thats about the same size as your Yak.
http://www.rcuniverse.com/product_gu...fm?kit_id=2754
Sounds good to go.
root