Panther Sport Aircraft Forums

I'm looking forward to seeing your performance numbers, when you get your Panther in the air.
Glen

GlenNJ wrote:Tony,
Is the cowl for your Jabiru 3300 based on the Corvair cowl, or the universal cowl? Looking at the pictures of both cowls, it looks like the Corvair cowl has smaller cheeks.

Glen

Glen,

Corvair cowl. The Jab plug was made by mating the front 1/3rd of a RANS S-19 cowl to the original Panther cowl. Inlets are closer together, so it uses an 11" spinner and not the 13" spinner on the Corvair and universal cowls. I didn't like the big inlet for the oil cooler so I cut it off and rolled my own.

Tony

Tony,
Is the cowl for your Jabiru 3300 based on the Corvair cowl, or the universal cowl? Looking at the pictures of both cowls, it looks like the Corvair cowl has smaller cheeks.

Glen

If you're thinking about the 3300 and didn't make it to S&F, here are a couple photos of the Jab Panther cowl:

https://picasaweb.google.com/tonyboytoo ... 6563284946

https://picasaweb.google.com/tonyboytoo ... 7336299618

Tony

Posted by Frank Edwards 4/28/2014
Hi Tony,

Sorry but the Rotec TB was not discussed when I was there, a freind has one on his 2200 and he is quite pleased with it after some set up issues. He is an economy freak leaning out to get 12lt/hr to get range from his Corby Starlet that only has 50lts available.

Hydraulic lifters work, but have taken reliability out of the engines, feedback I have heard is the 50 grade of oil is too heavy for the lifters, car oil is much thiner. My engine rebuilder who I trust says about 600 hours is the limit with one of these engines before you need to look at the heads. When I bought my Jab it had 260 hours and needed the through bolts replaced as part of the SB, at this time my exhaust vales were replaced (pitted) and the lifters changed to the high leakage type (next generation), one was faulty when he installed it out of the packaging, lots of cursing. Then after more problems we discovered that the pushrods needed to be 2mm shorter with the new lifters - hopefully all good now for quite some time.

The feeling that I got from alot of people who own engines at Natfly was Ian is making good improvements to the engine design, probably not all necessary as you suggest and I am sure Rod Stiff does not agree, especially if he loses some engine sales.

The jab is still a great engine when properly cooled and I am sure you will be happy with your purchase and suppoert from Peter, this just gives us some more upgrades/engine options that should either prove themselves with time or prove Rod Stiff right not to make any changes, we will just have to wait and see, but we will all be winners either way.

Regards,

Frank

Posted by Tony 4/26/2014

Hi Frank,

Thanks for posting the photos. Ian's engine is a nice looking powerplant! Some observations on my part:

1. The 20 amp PM alternator supplied with the Jab will most likely meet the needs of the majority of users. The belt driven alternator adds weight, complexity, and robs a few horsepower.

2. Corvairs, Lycomings, and a plethora of other engines have been running successfully with hydraulic lifters for a very long time. Why did Ian feel it necessary to go back to solid lifters?

3. Some swear by the Bing, others swear at the Bing. Did use of the Rotec TB come up in your discussions with Ian?

4. I wouldn't necessarily call all changes "improvements". Most likely neither would Rod Stiff!

Anybody else with an opinion please feel free to jump right in.

Thanks again for posting the photos.

Tony

Posted by Frank Edwards on 4/25/2014

Hi Tony,

I have just got back from natfly and the Camit tent was very very popular with a keen interest from alot of people in what they have done. In summary they have made incremental improvements to known issues, they will be selling for the experimental market and will still be manufacturing and assembling engines to the Jabiru sprecification for Jabiru. They have an engine with 300 hours on it will no signs of wear or distortion. I think it is great for the Jab engine that further development work is going on. Engine has gained about 2kg

Changes that I noted are:

New cylinder head material with improved thermal expansion capability meaning less re-torque of head bolts

Increased size of through bolts

Increased material thickness of cylinders

Improved valve geometry to reduce valve bush wear

Inhibitor injection to prevent rust if not run for a period of time

40A alternator at the rear of the engine with Honda coils Regards,

Frank

Posted by Frank Edwards 4/10/2014

Hi Tony,

I fly behind my own 2200 engine so I have a good interest in jab engines. They are great value based on price, weight , power​ and Aussy made is a bonus these days.

You are right properly cooled and used regularly they are reliable and reach TBO. Most ongoing issues here are heat related and mainly with the 3300 that go into the J230. The factory does not install CHT sensors on all cylinders and some pilots operate aircraft like they look after their cars if you know what I mean. I will be following your progress closely because I plan on fitting the 3300 into my Panther when the time comes.
I will let you know what the Jabs/Camit are doing at Natfly.

Regards,

Frank

Posted by Tony Spicer on 4/10/2014
Hi Frank,

The Jab engine mount was finished just prior to S&F, so that's the extent of the progress to date. Once the mount is modified to accept the Rotec TB Pete Krotje will mount a 3300 on a mock firewall and adapt the current Panther cowl to fit.

I must disagree with your "lack of efficient cooling" comment. When properly set up, the Jab cools just fine. I first started flying a small head 3300 15 years ago in a Sonex. If anything, it ran too cool. A 3300 powered Zenith 750 at our local airport had no cooling issues. The 750 is just slightly faster than a flying outhouse.

The Camit engine might be a viable option for you Aussies, but I prefer having an engine that I don't have to ship back to Bundaberg for warranty work!

Hopefully I'll have a fuselage kit soon and can press on with the building.

Be sure and give us an engine update after Natfly.

Tony

Posted by Frank Edwards on 4/10/2014

Hi ​Tony,

I have just seen you photos for the Jab engine on your build site, how is the rest of the firewall package going with JabUSA?

There has been a few developments in Aus with Camit and Jabiru. Camit are now selling their own engines direct to the homebuilt community - not quite sure how the business relationship works, but they have worked together for a long time. Camit have made a few design improvements, they have beefed up some of the known problems with through bolts, cylinder base web thickness, valve guide/gemometry and only supply solid lifter that should really make this engine reach TBO without the valve issues caused by lack of efficient cooling. We have our annual fly-in (Natfly) next week and I believe Camit will be there as well as Jabiru so it will be interesting to find out more information on what they have done to the engine.

Hurry up and get yours finished (only joking), I am really interested in how it goes as the power to weight ratio should be great.

Regards,

Frank