Provisions to add temp risers on baffles??

MS19087 · #1 02-21-2009, 07:52 AM

I'm finishing up my baffles and noted that some builders installed nut plates on the aft end of the inlet ramps to accommodate (in future) some sort of riser to prevent airflow in the event these cylinders run too cold . . . is this worth doing? Is this a known issue? I'm running an IO-320 (165hp).
Thanks for comments!!

JonJay · #2 02-21-2009, 08:34 AM

You will most likely need to add in air dams or a riser for #1. It usually runs a lot cooler due to the orienation of the cylinder fins and the ram air it is exposed to. Nut plate are fine, but most just put in a piece of angle temporarily with duct tape until they get the size right then rivet them in.
I just drilled through and pop riveted mine in.

Finley Atherton · #3 02-21-2009, 02:59 PM

See http://www.vansairforce.com/communit...ad.php?t=30427 for some suggestions.

Fin 9A

db1yg · #4 02-21-2009, 03:15 PM

Hi Mark,

I riveted my air dams in place using all aluminum 3/32 rivets from McMaster Carr. Three of these small rivets are plenty strong for the application and if you need to change the size of the dam they are drilled out VERY easily with no increase in hole size. As a matter of fact, I used these little buggers to temporarily hold a number of skins on the plane as I was fitting various components--later drilling out, dimpling, and replacing with solid rivets.

My experience was that it took 3 tries to arrive at the best compromise in dam size for climb and cruise cooling balance.

Cheers,

db

Jim P · #5 02-21-2009, 04:42 PM

I installed nutplates for risers myself, figuring that the shape of the risers was TBD until I'd flown a bit. In testing, I just used aluminum tape on the fins until I got the shape right.

MS19087 · #6 02-23-2009, 11:46 AM

I spent 10 minutes installing nutplates on ramp in front of Cyl#1 - figured it was time well spent!! Thanks for your input!!