Lower Cowl doubler for O-200 STC

[matthewhinmann120cm]

Hello all,

I’m currently in the process of installing Randy’s O-200 STC in N120CM, and wanted to see if anyone knows what the lower cowl doubler looks like (does anyone have pictures of current installations?), and does anyone know where I can find one? Is this something I can make myself? What’s the actual purpose of the doubler?

Ive been trying to find information on this doubler, and it seems kinda hard to find….


I would appreciate any input

Thanks!
Matt

[6641]

Have one I made for my 46 using a shrinker and stretcher.
In my opinion the 46 cowering already has too much airflow so I made a second one which blocks off more airflow.
The 47 cowel has less flow and generally runs hotter. (IMO)
See private message to text me for pictures.
Joe

[6298]

The purpose is to draw more air thru the cowling. There are three different cowling shapes, and it’s best to fabricate one. Basically it’s a lip facing down at a 45 degree angle. 11/2 to 2 inches wide. There is one shown in the parts catalog as part of the summarization kit.

[matthewhinmann120cm]

Thanks for the information, I didn’t realize there were 3 different cowl shapes. What’s the difference between the cowl designs?

My lower cowl currently has a silicon/rubber type “chin” or doubler lip. Is that part of the old design cowl, or a newer type?

[phil123]

This might help, I just bent two pieces of straight .032 to about 45 degree's and riveted them on.

[6643]

My lower cowl currently has a silicon/rubber type “chin” or doubler lip. Is that part of the old design cowl, or a newer type?

That would be a modification. There were no cowls from the factory with other than an aluminum lip.