# Mazda Rotary Engine

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#### Vigilant1

##### Well-Known Member
He offered his email address. Have you contacted him? Cryptic response
Yes, cryptic. Is it a business without a web page? (The old Powersportaviation.com site is gone). Maybe some specs, prices, availability info?
If the "new Powersport" is simply an email address, then we can assume things are at a very early stage.
This would seem to be a very good place and opportunity to publicize their efforts and product. Powersport had a very good reputation, and if the present product is the same it would have no problem withstanding close scrutiny and discussion.

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#### AIRCAB

##### Well-Known Member
Only one of the last superlites used the braised housings. Never run thru tests. Now at the EAA museum. For the superlite that they tested with they had done aluminum end plates that they did with coatings. They found the coatings difficult and tricky to apply. They questioned the durability of the coatings. That was why they did the braised steel housings. The intent was that the steel housings could then be nitrided to emulate the standard cast iron housings. Probably the best possible surface for the side plates. Regardless of the plates the engine was amazing. The lightest was 178 pounds lacking only the radiators. Those are going to add some weight but you are looking at a 1 pound per HP engine making over 200hp
Bill
I would think the best possible surface would be chrome like the rotor housings. Grinding the HardChrome flat would be relatively easy.

#### AIRCAB

##### Well-Known Member
O
Yes, cryptic. Is it a business without a web page? (The old Powersportaviation.com site is gone). Maybe some specs, prices, availability info?
If the "new Powersport" is simply an email address, then we can assume things are at a very early stage.
This would seem to be a very good place and opportunity to publicize their efforts and product. Powersport had a very good reputation, and if the present product is the same it would have no problem withstanding close scrutiny and discussion.
Okay, I look at it as the website is gone, so there is no interest in selling engines. I am not sure if they ever sold any engine packages, and it they did, then keeping the email address active allows some form of support. But then again maybe I am looking at it wrong.

#### AIRCAB

##### Well-Known Member
RedBackAviation did a rotary article, with a update in 2020.

#### Lendo

##### Well-Known Member
AIRCAB, Yes! I sent him an e-mail and asked for specifics, but the fact he has no Web Site and his E-mail address ends with .org, might imply something. No response as yet.
BTW Billet Rotary is the local chap. I'm on the Nth West Brisbane, he's on acreage south and just out of the Brisbane metropolitan area. Nice Chap very genuine.
George

#### Lendo

##### Well-Known Member
AIRCAB, Billet Rotary has expanded their products considerably and Pac performance seem to do a good job as well - nothing is cheap.
Both seem to cater for the Drag Racing market, we are more interested in Reliability over a much longer time. Not to say their not reliable products , on the contrary. their top range products, but our requirements are different, in terms of tuning for our rpm range. Size of the P-Port and the sealing of the Port are very important.
At least you can buy more cheaply with the exchange rate.
I do like the center bearing available.
I haven't looked for a long time now, good to see products and range improving - I need to win Lotto!
George

#### rv6ejguy

##### Well-Known Member
He offered his email address. Have you contacted him? Cryptic response
Yes, I have contacted him, no response as yet. Why post on this discussion forum if you don't answer direct questions? Does he want to sell engines or not?

#### AIRCAB

##### Well-Known Member
Yes, I have contacted him, no response as yet. Why post on this discussion forum if you don't answer direct questions? Does he want to sell engines or not?
Yes, I get that.

#### rv6ejguy

##### Well-Known Member
I received a reply from Powersport today. They are working on the website. FWF weight around 325 pounds, cost between $20and$35K. Up to 250 hp.

#### Lendo

##### Well-Known Member
rv6ejguy, one thought me may be testing the market. I haven't had a response yet, 325 suggests cast Iron housings, 250hp suggests Peripheral ported (PP), however we know ports can be too big which reduce inlet velocity and Volumetric Efficiency. Keeping the RPM down for longevity and power up requires a good balance. I've never liked the 2" PP for the reasons mentioned. My preferred RPM range is 6 to 6.5K with 6 K for cruise. However some my like that 250hp range, then it's a step-up in rpm and PP size.
George

#### AIRCAB

##### Well-Known Member
rv6ejguy, one thought me may be testing the market. I haven't had a response yet, 325 suggests cast Iron housings, 250hp suggests Peripheral ported (PP), however we know ports can be too big which reduce inlet velocity and Volumetric Efficiency. Keeping the RPM down for longevity and power up requires a good balance. I've never liked the 2" PP for the reasons mentioned. My preferred RPM range is 6 to 6.5K with 6 K for cruise. However some my like that 250hp range, then it's a step-up in rpm and PP size
rv6ejguy, one thought me may be testing the market. I haven't had a response yet, 325 suggests cast Iron housings, 250hp suggests Peripheral ported (PP), however we know ports can be too big which reduce inlet velocity and Volumetric Efficiency. Keeping the RPM down for longevity and power up requires a good balance. I've never liked the 2" PP for the reasons mentioned. My preferred RPM range is 6 to 6.5K with 6 K for cruise. However some my like that 250hp range, then it's a step-up in rpm and PP size.
George
I would be interested to know how many core engine components are new (OEM) , if any.

Steve

#### Lendo

##### Well-Known Member
The biggest issue to my mind is the Peripheral Ports, if not done right they will leak. I spoke to an engine builder locally, he had the best results with welding them in, other use high temp epoxy, the void filled and sealed under vacuum. I'm hoping someone develops a better system but can't think of anything myself, it needs to be the designed by a top-notch mechanical engineer.
George

#### AIRCAB

##### Well-Known Member
The biggest issue to my mind is the Peripheral Ports, if not done right they will leak. I spoke to an engine builder locally, he had the best results with welding them in, other use high temp epoxy, the void filled and sealed under vacuum. I'm hoping someone develops a better system but can't think of anything myself, it needs to be the designed by a top-notch mechanical engineer.
George
Look at Chips Motorsports on utube.

Interesting!

#### Lendo

##### Well-Known Member
AIRCAB, Thinking about it there is a lot of CNC work for that approach and I don't know if it may weaken the area of that housing and this is just the sealing, the boring and fitting of the inlet tube has to be done. There may be an easier way, however it is the sealing that has to be right and 'O' rings definitely have their part to play to cater for expansion and contraction, to avoid leaking.
George

#### AIRCAB

##### Well-Known Member
AIRCAB, Thinking about it there is a lot of CNC work for that approach and I don't know if it may weaken the area of that housing and this is just the sealing, the boring and fitting of the inlet tube has to be done. There may be an easier way, however it is the sealing that has to be right and 'O' rings definitely have their part to play to cater for expansion and contraction, to avoid leaking.
George
His tube design is sealed at the base, and he has also designed and manufactured sealing plates to avoid the epoxy fill in, which eventually fail. A lot of his current work is for customers building 4 rotor.

#### Armilite

##### Well-Known Member
The smallest engine would be the 100 HP Rotax 912 in the RV12, which makes up a very small percentage of the fleet at this time. I'm having a really hard time figuring out how the total number of manufacturers who managed to get their name in Kitplanes over the years (all it takes is emailing some kind of info pack to the mag) has any bearing whatsoever on the number flying, either in total or by manufacturer. By that logic, there are effectively only two certified engine mfgrs in the US, so there are almost no engines flying. Or, since technically, there are other engine mfgrs, each one has the same production volume as Lyc or Cont.
==============================

You have Kits made and you have Kits Built and still Flying. Kitplanes try's to keep a Database updated Yearly.

Since the 1st RV-1 and going up to his latest the RV12, Power by the Rotax 912 100hp Engine, it's only Logical you will need more hp as they get Bigger and Heavier! With the RV12's MTOW at 1320 lbs = 598.7419 kg / 10 kg = 59.87419 kw needed = 80.29261 hp.

RV1 MTOW: 1,065 lb (483 kg), Powerplant: 1 × Lycoming O-290G Horizontally opposed-piston, 125 hp (93 kW). You can Over Power just about any Aircraft, People like Speed.

You have Options today:
Rotax 912 80hp
Rotax 912 100hp
Cont. O-200 100hp
Lycoming O-235 105hp
Rotax 914 Turbo 115hp
Rotax 915 Turbo 140hp

Rotax Rick 670 92hp

Are there a few Engines made overseas that could work 80+hp, probably!

#### Lendo

##### Well-Known Member
AIRCAB, what size PP is he recommending?
George

#### Urquiola

##### Well-Known Member
The biggest issue to my mind is the Peripheral Ports, if not done right they will leak. I spoke to an engine builder locally, he had the best results with welding them in, other use high temp epoxy, the void filled and sealed under vacuum. I'm hoping someone develops a better system but can't think of anything myself, it needs to be the designed by a top-notch mechanical engineer.
George
A indicated, my ideal Wankel Engine would have one Rotor, Peripheral Intake Port, Reed-Valve controlled; 33 cm length intake manifold, for low load, low rpm improvements; and Side Exhaust Ports, as in Renesis.
See Ford patents CA1032477; CA1045553. All open and free download in Espacenet, but Atkins Rotary no longer sells single rotor shafts, the concept looks good for street cars, but this is an aircraft site.
Data about NSU Wankel Spider come form a Mira Alvis publication, chart from a reciprocating engine is from the web.
Larger surface in Wankel working chamber may worsen the quenching, flame extinction, main cause of emissions at high rpm, high load, while leaks are the bad side at low rpm, low load (GM research, also pointed a hotter rotor surface means less HC in exhaust)
Toyota addressed the low load performance of RE by Reed-Valves in PPort, a glow plug in leading plug site (there are ignitors for heating devices and micro turbines) Air cooled Wankel, by working at slightly higher temperature, improve the quenching issue. Blessings +

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#### Urquiola

##### Well-Known Member
The biggest issue to my mind is the Peripheral Ports, if not done right they will leak. I spoke to an engine builder locally, he had the best results with welding them in, other use high temp epoxy, the void filled and sealed under vacuum. I'm hoping someone develops a better system but can't think of anything myself, it needs to be the designed by a top-notch mechanical engineer.
George
0% leaking is the best, but about leaks in real world, the issue may be how much, when, where, what type of fluid leaks,...
A bit leaking can be tolerable, negligible; or not?
Does it make sense using oil as cooling fluid instead of water with additives? At least, block won't break if temperature goes freezing in Winter...
Blessings +

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