Plenum Kit options
 

I have the Sam James cowl and plenum baffle kit.

At the time I bought it, the plenum kit was a piece of fiberglass and some fullsize drawings that you made the metalwork from. This did not turn out well for me.

Are there any other options for a ready to assemble plenum baffle kit?

Ted

What engine, and cowl do you have? Long cowl?

O-360 straight valve, carburated, I do not believe its a long cowl, fixed pitch Catto prop with 1.5" (I think) extension.

I have no issues (or install issues) with the James Cowl & carb intake, which I intend to keep, but those metal rings I would like to connect to something else.

Ted

Plenums
 

Ted,
I did the SJ cowl/Plenum/intake for my -6.
I was happy with the cowling and intake parts/instructions.
But the plenum fit and paper cut out plans for the baffling were very poor.
I did buy the Vans baffling kit and had several unused pieces but the computer cut pieces are wonderful to work with. You do have to do fiberglass work to get the plenum to fit correctly as well. How much is up to you and what you will accept as acceptable.

I wish there was a KIT that was bolt on. I do not know of one.

Bob, I'm right there with you. Looking for a plenum kit with Van's level fit and finish. Maybe VAF as a group could come up with a design or two and use it towards VAF expenses.
I (my own opinion here) would like VAF to host all the photos and files (and maybe that happens now) so they don't disappear when the links go stale in a few years. But that costs $$$ in equipment and increased bandwidth. Quite expensive.

Matronics has been hosting it's own photos for years, supported only by donations. Almost all other forums host their own photos, including automotive forums that have much higher traffic than any aviation forum.

I guess since it's Texas, the expenses are bigger, like everything else.

What is needed is a mold. Several people have used the Van's top cowl as a form to make a throw away fiberglass plenum top. From that they make a wood form box that is identical to the installed baffles. The throw away piece of fiberglass is than the bottom of the box. Some prep to make the inside smooth and you have a plenum mold. The problem is these are all one off.

I used the James cowl and plenum on the RV-10 and made the baffles per the James instructions to fit the plenum. Not all that hard and I recommend the products. For the RV-8 project however I decided to stay with the Van's cowl and make a plenum. I'll do the above procedure. I'll see how hard it is to make a reusable mold if anyone is interested.

I suspect the hardest part is making the transition from the plenum to the cowl inlets. The James Cowl rings and plenum make this easy. I'm stealing ideas from others that have made a plenum for the stock cowl.

Carl

Mould
 

It's a pity you are not in the UK, I made my own plenum and have a Mould.

I used the Van's baffle kit as a starting point and the plenum top is screwed to this. I reshaped the cowl with 5 inch circular intakes and used neoprene to join the cowl to the plenum.


It works very well.

Multiple Molds
 

I will be back making some parts in 6 months if enough people need them. For now I have to finish my airplane. The following molds are for parallel valve, RV7, long cowl. Don't know about the clearance for the short cowl. Some checking would be in order. The cover has a stiffening core, post curing to 250F and is vacuum infused. The inlets are layups with vacuum bagging. The total weight is about equal to the baffle material roll provided with the baffle kit.



One inlet:


Plenum Cover - Post cured part is darker.

Nice looking work Bill.