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I've always thought the universal cowl was rather boxy and ugly.
So, I fell in love with the nose of the Panther. Big, chubby cheeks. I knew my family would not support me building a Panther, so what a quandary.
At Airventure, I had a momentary loss of self control and ordered the Corvair/Sonex nose bowl from FlyPanther. Its built for the Corvair, but I was sure I could fabricate it to mate with my Jabiru. So now my quest. Mate the cowl to the plane. Things are looking good.
I need to remove the short prop extension required for the Sonex cowl and reinstall the longer one stock with the Jabiru. This gives clearance to the bottom of the engine and oil cooler. The intakes are misaligned so I will need to fabricate plenums to channel air to the existing shrouds. More to come.

Looks Great! I've always like the look of that cowl as well. Once you have it up and flying, let us know how the engine cooling is affected by this change.

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When fitting my stock universal cowl to Jab 3300, I added a 5/8" thick spacer between prop and hub to allow pulling cowl forward for more clearance and cooling. Do not know how much longer a prop hub you need, but if less than full 2", Ian Bent's CAMit makes 1" longer ones as well as 2". and may make a custom length to order One advantage I found with my spacer, an aluminum doughnut, is that when holes are precision machined to match the hub (bolt circle was about 0.002" less than the nominal size), and longer bushings machined for snug press fit into those, the bushing are positively held square and cannot tilt in the soft wood prop is bolts get a bit loose. I think Prince has a spacer that takes a similar approach making the bushings integral to the spacer but not sure how snug a fit those are to the prop hub which is critical concern on Jabiru engines. Just some options to consider if full 2" longer hub does not look right. Photos look great, and longer inlets do help. Be sure to take into account the spiraling airflow from prop that tends to throw air up and over the # 2 cylinder causing it to run hot.

David A. Sonex TD, Now with CAMit 3300.

Hi John,
The new cowl looks great!! Post some pics when your finished. Will you be attending airventure 2015? Let us know how the cooling works compared to the old cowl.


Michael RADTKE
Waiex N143NM

Here's an update. We wrapped the cowl in 3M vinyl, the spinner in carbon to match the P-tip and I couldn't resist the Ruby Tip.

Test flying the new cowl with another Jabiru Sonex shows a slight speed advantage. Same prop. Oh, and cooling, its better.

Comments?

Looks great!

John,
The cowling and the spinner look really nice.

That looks really nice. Can't wait to see a couple pictures of the whole plane featuring that nose.

John,

You posted some low res pictures of the initial work you did. This would be a great subject for a more in-depth writeup on the process. Maybe a good topic for the association newsletter?