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Posted
As a point of interest I was in Bundy doing a job for my work and then had to get some parts from Bunnings for the farm this weekend here. I dropped into the Jab factory to see if I could get a brochure on the new 6cyc gen4 engine....bargain bonanza I got a private tour with Sue through the factory and the cnc machines and the new parts and 1 piece cast blocks and the machining of such. It was very interesting I will say. They seem to be doing the right things from what I saw also taking a steady steady approach to development. I did like what I sawThey also have some ex Camit people there as well.

Well, I am now confused! (doesn't take a lot, I admit, but I am at least a step ahead of the piece of paper with 'Other Side' written on both sides..)

 

On the Jab. website, the engine piccies show the new barrels and heads mounted on 'Gen 3' machined crankcases.

 

So: is what Jabiru currently show, now been surpassed by another version?

 

 

Posted
Well, I am now confused! (doesn't take a lot, I admit, but I am at least a step ahead of the piece of paper with 'Other Side' written on both sides..)On the Jab. website, the engine piccies show the new barrels and heads mounted on 'Gen 3' machined crankcases.

 

So: is what Jabiru currently show, now been surpassed by another version?

If you have a close look at the four cylinder engine, you will notice that the crankcase IS a casting, whereas the six is not.

 

 

Posted
Then perhaps I have the wrong browser. What mine shows ( http://www.jabiru.net.au/images/documents/2200_flyer.pdf ) has an obvious join line down the centre and has been cnc machined. That would require through-bolts to pull it together.Could you please point me at the url for the new version?

That is the correct photo. They are a two piece housing and they still require through bolts, albeit longer bolts.

We have a brand new J170 and a brand new J230 at YCAB. The new cast crank case is very similar to the old CBC machined ones. The mating surfaces have been machined. They are definitely not one piece units.

 

 

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Posted

Doh its ok I was caught offguard with the impromtu tour..yes it is a split block with 2 blocks back to back now I think about it as it was a quick tour around. Sorry for the confusion. I was so impressed by what I saw....no I am not on those sort of drugs. I found some pics on a older thread..I am reposting them here incase others like me forgot

 

3d3cc3ab-f92b-45d5-9b12-025a3e575658.jpg.43c46d7c7e23a02201945e62f071fecd.jpg

 

eb38eb85-6753-4d66-b90d-73a1dd26215a.jpg.9b4b0652ece490b30311ce9d2d4ebf0d.jpg

 

b107404b-7097-4015-985d-e4c12929d7b6.jpg.2219a50b0064d9f9a077b4c49f6485d2.jpg

 

98993796-5ddf-4b5e-ae83-46d7de261f20.jpg.06a7a08b1069ad0e9e982cf08efca063.jpg

 

 

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Posted
That is the correct photo. They are a two piece housing and they still require through bolts, albeit longer bolts.We have a brand new J170 and a brand new J230 at YCAB. The new cast crank case is very similar to the old CBC machined ones. The mating surfaces have been machined. They are definitely not one piece units.

I am bemused at what appears, then, to be a fully externally-machined cast crankcase. An unnecessary expense, surely, for external, non dimensionally-critical or mating surfaces?. Most unusual.

 

I note that the sumps for both the engines on the Jab. web-site remain castings - as they have been since the first ones.

 

 

Posted

The castings look really neat..possibly cast in a small vacuum. There was machining on them but mainly flat areas machined and it looked very good but there was a lot of cast still visible and also just cast surface on the inside.. Maybe they hadnt finished them. There were about 10 on a pallet that had been machined and I saw one in the larger VMC. I wish I had pushed now to take some pics

 

 

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Posted
Looks great. They should sell like the proverbial, particularly the six.

The six is particularly smooth. I flew the 230 to Bundi for a scheduled service. The new motors use practically no oil in 25 hrs. The new cast crankcase has the fuel pump set back closer to the flywheel so that it can be removed without first removing number 5 cyl. Cooling fins on the new cylinders are much larger.

 

 

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Posted

Unfortunately the inlet tract and carb appears to remains the same, so the mixture distribution may be still compromised , otherwise it seems to be a great leap forward. Lets also hope that the oil resevoir is a little bigger, oh yeah and the rocker bushes have a greater oil flow to them. And that the generator is not the same "on the end of the crank" affair. Oh dear! what am I saying? Ally barrels do not a new engine make.....

 

 

Posted
fully externally-machined cast crankcase. An unnecessary expense, surely, for external, non dimensionally-critical.

Probably sells 20% of their engines, although I don't think this one looks as good as the last.

 

Unfortunately the inlet tract and carb appears to remains the same, so the mixture distribution may be still compromised ,

Bet the awful combustion chamber is the same as before too.

 

Australia has a couple of the world's best engine guys in the area of chamber, port and manifolds combo. A week with any of them would result in a leap forward in power and cooling.

 

 

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Posted
Found a USA brochure

Aha, in the photo from the USA brochure, it is obvious ( and stated, can't doubt that!) that they are cast crankcases, very nice castings indeed.

 

 

Posted

Havent seem a pic yet of 3300 with cast case yet

 

2200 have cast cases, 3300 do not.

 

Last time I was there, the large stack of broken 3300 were kept to be upgraded to new models - not a bad thing as the old cases rarely had problems other than crook assembly

 

Maybe with CAE gone the urgency has ramped up

 

I was told the sump casting was very expensive and it was updated just a few years ago.

 

 

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Posted

"The camshaft is provided by a specialist camshaft manufacturer".

 

Well it's good to know they're not using a hairbrush manufacturer.

 

 

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Posted

Nothing wrong with the way the first hydraulic engine looked and upgrades sounded good too.

 

Flight time and operating cost will tell

 

 

Posted
Australia has a couple of the world's best engine guys in the area of chamber, port and manifolds combo. A week with any of them would result in a leap forward in power and cooling.

Bex......More info please.

 

 

  • Agree 1
Posted
Bex......More info please.

All stems from decades of, and the ongoing work on 2 valve Ford, Chev and Chrysler V8s, there a handful of guys who spend their lives devoted to finding more power and efficiency from them and share their work.

 

The last 20 years has seen great jumps with a change of thought away from swirl that has seen leaps forward in HP across the range, and keeps the 2 valve Chev V8 as powerful and as fuel efficient as 4 valve heads.

 

Here is an example from Tony Knight in Adelaide of what he did with a Datsun head that could be partially applied to a Jabiru design ..

 

Incredible Datsun Cylinder Head Redesign - Race Magazine

 

This is completely applicable to a slow revving engine such as the Jab as the physics doesn't change as long as the applicable parameters are met, such as port, valve sizing, manifold shape and lengths etc. and it's very important they are matched.

 

Someone like Tony, other well known guys are mentioned in the article, would comfortably get 5 hp more at 3300 rpm and suddenly the Jab 2200 is a 100HP unit, or the same 80HP but at lower rpms and with better fuel efficiency.

 

 

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Posted

Jabiru, and Rod in particular, takes advice from no one.

 

Would love the experimental market to be big enough for someone to make aftermarket bits, Rotec have a go.

 

There are aome in EU who fit turbo and efi.

 

 

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