I think I have problems with cooling on my Sig Extra with an OS 1.6.. it's kinda like it leans out a little in the air.. Anyone have any pics of their cowel/engine installations that could show me how much you cut out to let air out??

Thanks,
Deck

In the assembly manual it states " If you are using a 2-stroke engine such as the Irvine 1.20 or 1.50 or a 4-stroke such as the Saito 1.20, 1.50 or 1.80 we suggest using an opening which measures 6.5" long from front to back, 6.5" wide at the back edge by 3.5 " wide at the front. This allows room for the pitts style muffler and adequate cooling area, with plenty of air for 4-stroke engines." From personal experience I can tell you that failure to give a large displacement engine adequate cooling area is going to cause you big problems. I know it don't look so good but that engine will seize without enough room for the air to exit the cowl.

Do it like the manual says. It works very well.