James Cowl boot questions

Charles in SC · #1 01-02-2018, 06:08 PM

At long last I am coming to the point of fabbing the connecting boots between the plennum and intake. How much should they overlap the fiberglass on the cooling intakes and the throttle body intake? Should I use hose clamps to secure them? what kind of glue or system should I use to create the seam? Any other tips will be appreciated. As always Thanks in advance!

Carl Froehlich · #2 01-02-2018, 06:44 PM

This is the cement to use. I got the 4oz can as it keeps better:
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

Use a butt joint on the neoprene. Follow the directions on the can. The joint comes out amazingly strong.

I use a hose clamp at each end, not too tight. The boot goes over the aluminum ring about an inch. It goes over the plenum inlets Perhaps two inches. If you make the boot right it should pretty well stay in place with no hose clamps, but use them anyway. The boots should be a fairly snug fit. The side of the neoprene that has the fabric goes on the outside.

Carl

Charles in SC · #3 01-02-2018, 07:27 PM

Thanks Carl that is exactly what I needed to know. You even answered one question I forgot to ask. Does the fabric go inside or out? Do the boots last well as in for years or weeks etc?

Carl Froehlich · #4 01-02-2018, 07:36 PM

Quote:

Originally Posted by Charles in SC

SNIP Do the boots last well as in for years or weeks etc?

Years if you make them right. My first set on the RV-10 lasted two years - but I really screwed them up. The second set is now five years old and look like the day I made them.

Carl

rockwoodrv9 · #5 01-02-2018, 08:25 PM

Charles, email me and I will send you some pictures. I made the carb intake removable with a set screw and I can slip a scat tube over the FAB snout from the outside. I had trouble making it work installing the scat after the bottom cowl was on.

The cooling intakes, I used scat tube there too. They are about 3" long and there is about 1" between the ring and plenum. My plenum may be different - it is not a James plenum.

Have fun!

BillL · #6 01-02-2018, 08:42 PM

Quote:

Originally Posted by Charles in SC

At long last I am coming to the point of fabbing the connecting boots between the plennum and intake. How much should they overlap the fiberglass on the cooling intakes and the throttle body intake? Should I use hose clamps to secure them? what kind of glue or system should I use to create the seam? Any other tips will be appreciated. As always Thanks in advance!

Just like Carl said - works well. I made a practice piece, there was plenty of material. Like Carl, I made mine a tad small for a slight stretch fit. I clamped the first end, applied glue the squeezed together and clamped the other side to keep the ends together and applied a final seam on top. Smooth on the inside and a slight bump on OD.

KatanaPilot · #7 01-03-2018, 05:54 AM

Has anyone with the James Cowl tried SCEET hose instead? If so, any Pireps?

The neoprene hose idea doesn't seem durable enough, but it sounds like some of you have had good results.

Carl Froehlich · #8 01-03-2018, 09:00 AM

Quote:

Originally Posted by KatanaPilot

Has anyone with the James Cowl tried SCEET hose instead? If so, any Pireps?

The neoprene hose idea doesn't seem durable enough, but it sounds like some of you have had good results.

I don?t recommend SCEET or SCAT hose for this function (especially SCEET). They are simply too inflexible to handle the relative motion, over this short span, between the engine and the front of the cowl (as in something will eventually fail). The neoprene does well for this application.

Carl

KatanaPilot · #9 01-03-2018, 10:58 AM

We had a good deal of discussion at Synergy about this. They had not done a SJ cowl in a while and never a Bill Lane plenum (which the folks at Synergy were quite impressed with).

The diffusers line up perfectly with the SJ cowl rings, but we know there will be a lot of torque generated movement between these two components. So the neoprene it is and I'll use the SCEET hose elsewhere.

rockwoodrv9 · #10 01-03-2018, 12:37 PM

My plenum is a BillL design and build. I modified it a bit to fit the O-320 and I glassed the intakes to the main plenum making it one piece. The distance between the ring and the front of the intake is about 3/4" - 1". The flex tubing fits on without the need for bands.

Here is a picture of it while I was working on it. If you want a picture of it finished, email me.