New baffling

[Steve Pierce]

We originally built my baffles as the VAN's drawing shows. Since my oil cooler was behind the #4 cylinder and I was having oil temp problems we extended the left rear baffle back about 2 inches. It made no difference in the CHT or Oil temp. Putting the original leather seal around the air filter-lower cowl dropped the oil temp and CHT. On the #3 side it has always been right up against the cylinder and I have no temperature issue there either.

I thought the first revision where we moved the cooler back helped drop the oil temperature?

[Gilbert Pierce]

I thought the first revision where we moved the cooler back helped drop the oil temperature?

Didn't help.
The seal around the air intake was the only thing that effected the temps. I even put vertical angles on either side of the cooler inlet like the guys on VAN's forums recommend. I didn't see any improvement with that either. The secret is lowering the pressure in lower cowl by stopping air from coming into it without going thru the top deck.

[Todd]

Thanks Gilbert. AC 23-27 is a common sense document. I'm making good use of it in my rebuild. Thanks also Bill for the reference. Airforms look like the ultimate solution, probably cost-effective if installed by a mechanic charging for his time compared to paying a mechanic to assemble and modify Van's kit. I have a knack for doing everything the hard and slow way, so will continue with Van's.

[Andrew K]

The secret is lowering the pressure in lower cowl by stopping air from coming into it without going thru the top deck.

I very much agree with this. I had good baffling but wanted to lower my temps more and a local pilot pointed out a pretty good size gap between my airfilter housing and lower cowling that I overlooked and when we sealed it off my CHT reading dropped about 25 degrees during cruise. With no oil cooler on the Colt I was glad to see any reduction in temps.

[DougG]

I used Vans baffle kit for my RV-6 and then the drawings to redo baffles for the 290D in my Pacer. The old baffles were basically junk, this combined with the fact that the RV design is more efficient dropped the CHTs around 75 degrees. I haven't done it yet but planning on using the "doghouse" that keeps cooling air from slipping down behind flywheel. I think this was mentioned in the thread about the mystery Pacer as to how it cut down on cooling drag.

[idahopacer]

Well it's been a year since the last time this post has come up and I am now in the baffleing stage of my engine,ha ha. I am going from a O-290 to a O-320 so new baffles are in order, build my own or try the Van's RV-6.
What kind of rework of the RV-6 baffleing is necessary and were there any approval problems encountered?
Thanks, Idahopacer

[Steve Pierce]

Lots of trimming but the RV6 baffles for the O-320 work. We used them on a field approved engine swap. Airforms sells them ready to bolt on and far superior to original. http://www.airforms.biz/catalog/inde...1d626847ee3e5c

[rocket]

I have installed two sets of the Airforms baffles on C-206 aircraft and they are a superior product in every way. No B.S. They have a full kit for the pa-22 which is on my shopping list. Although…I am in the process of an owner assisted annual on a 22 where the owner fabricated a really nice baffle set for his baby. I mentioned that I might be willing to trade the inspection for another set of baffles.


Rocket

[idahopacer]

I should add that the oil cooler will be aft of #4 cyl. with the Stewart STC. Looked at those Airforms, nice but wow another $1000.00, Vans at $275.00 looks really good.

[Steve Pierce]

Time or money. Takes a lot of time to build even starting with the Vans set.