I'm a first time rotary builder and I'm in the process of porting a 13B for an RX4 club racer which will run a 48mm IDA. It's a 3B so the center ports are about 20% smaller than the primary ports. What's the general opinion on bridge porting the larger ports only and leaving the center ones non bridge port in an attempt to improve air velocity. Also, I've read many posts regarding removal of exhaust port inserts which I think is a good idea but Racing beat, who's templates I'm using, say don't remove them. Can I fit later model 13B turbo inserts?

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There are a bunch of ways to go.



Will the car be on the street at all, or onlt ona trailer to the track?



12A center irons have big tall ports and if you can weld up a big pile of aluminum on the stock or aftermarkt manifold to match those bigger ports, you can grind and match those to your hybred engine.



Or just bridge the secondaries (end irons) and be happy with that. It would still run fine on the street if need be.



The liners need to stay in place for all but full race 10,000 RPM engines. And even then some aluminum sleeves are welded in to replace some of the missing liner. The hole is just too big without it.



Lynn E. Hanover



Picture is a new aluminum housing with a replaceable iron liner.

interesting housing, what is that from?

That is from the future.



Now being developed for aircraft use where the aluminum is important.



The iron liner could be refinished a few times and then discarded at less than half the cost of a new piece.



Several versions are being tried. This version has be run on a dyno. More as it develops.



Nobody would want a set of these for a car would they?



Lynn E. Hanover

Lynn, as always price is important.

It's like an aluminum flywheel. Neat.



I wonder how well it transfers heat.

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Hi Lynn very nice work,

Why wouldn't you want these for a car :-)

What sort of pricing do you think these could be made for?

Would it be easier to have the support webs machined in the aluminium rather than

on the cast plate, then use a flat plate as the wear surface?

Is this designed for use with pport housings?



Regards

Michael

http://www.rotaryracing.co.nz

I don't know if the designer (Richard Sohn) has done anything on costs yet. There are a number of factors that must be investigated befire he needs to do that. It started as a project done for his own amusment, but has gained much interest.



On the plate and support pieces, The aluminum will grow with temperature a bit more than the cast iron. There would be an obvious advantage to having a reversable wear plate. But there is that problem with maintaining a dead flat surface at temperature. The next big step would be ceramic "Irons" with the wear surface just being the ceramic. Just a bit heavier than aluminum. Twice as stiff and no detectable wear after years of operation. Of course the permanent molds would be pricy, and the tooling all has to be diamond.



But what great pieces those would be. How about a ceramic set of rotors with tiny counter weights? The crank shaft could also be ceramic with cast steel bearing surfaces.



The object of this experimant is to develop an aircraft engine in the 125 HP range from a single rotor and still light enough to be effective.



Lynn E. Hanover