Engine Sourced - Our Shed

By: James Secher

To convert a 929 in to a rotary an engine is needed - happy hunting.

Engine Sourced - Our Shed
Cruisin’ in Caloundra on a Sat’dee night.

It’s been a long time between updates on Project Mazda. Still, headway has been made, and a potential rotary conversion date has been loosely set to align with Beachfest 2023.

Living on the Sunshine Coast, I’m lucky enough to have Beachfest on my doorstep. The annual event sees 800-plus classic cars descend on Caloundra for four days of car-enthusiast heaven. If you live in South East Queensland, I highly recommend checking it out.

 Not quite the purpose the General had in mind for the GTS, when it was originally created.

 Last year the kids and I checked out many of the goings-on in the rusty old Mazda. My kids are still completely infatuated with the Mazda or "Hot Wheels car," as they call it, and will jump in it the moment they hear it start, even if I’m just moving it in the driveway. We did a few laps on the Friday night Beachfest cruise, which was hilarious. I possibly had the crappiest car lapping the main street among pro-street cars and hot rods, but it didn’t stop my kids from waving at onlookers, like we were in a show car. The enthusiasm was worth the slight embarrassment on my part.

With Beachfest looming on the horizon, I’d set the goal to have the old girl converted to rotary power and on the road by then. So the clock was ticking big time at the time of writing. 

 This is the current donk, that is getting the boot.

Converting the 929 from a mild-mannered 1.8L piston family car to an obnoxious neighbour-annoying rotary is more challenging than expected. Rotary engines are few and far between nowadays, a far cry from the container loads that used to be exported to Australia from Japan in the late ’90s. Back then, you could get a front cut of a car for less than you’re average interest rate rise today. But the availability of donor engines is declining, with the last rotary-powered car finishing production in 2012. The occasional 12a or 13b engine is available through the usual online marketplaces, but most have little information or history. You can still buy a short block from Mazda for a princely sum, although I’m still determining how and where you can get your hands on one.

Then you have to pull apart the stock engine to perform porting upgrades and any other desired modification, making it quite costly. There are some businesses building brand-new full-billet rotary engines in Australia as well; they look amazing and, from all accounts, are as tough as nails, but this project does have some, shall we say, budgeting restrictions. I’m not sure I could get a $20K billet motor under the radar through the household bills account without some questions being asked.

 This pile of parts will hopefully make the Mazda 929 move to a different note.

So for the last few months, I’ve been watching all the usual forums and online groups, looking for parts to build an engine, or one already built with some trustworthy history. I phoned a few rotary workshops to see what they had and was told that they’d happily build a solid engine to whatever specs I’d like, but I still had to supply them with an engine to start. So my best option was to find all the parts needed and go from there.

I spent what some might say was an unhealthy amount of time looking for parts online.

One night on Ausrotary - (the rotary bible for cars and parts), I stumbled across a post with a heap of old Mazda RX-4 bits and pieces, that piqued my interest. A lot of stuff I didn’t need, like bumpers, doors, and lights, but in some of the grainy garage photos, I saw a few rotary housings and plates. I called the guy and asked what he had. I think he was surprised to hear from an actual human and not the obligatory, "Is it still available," message.

We had a good old chat; he had an RX-4 that he had knocked around in for years, built motors for it, some turbo, some not, and blown an engine or two, as, unfortunately, many of us rotary enthusiasts have. I’m sure he’d moved the car on years ago and was just getting rid of the spares from his garage.

Rotaries are, shall we say ... unique

I told him what I was up to in converting my 929, and he reckoned he had a lot of what I needed and enough bits and pieces to build a motor with spares to boot. All for $2500. It seemed like a fair deal, but unfortunately, as always, with great deals in car parts, there was a geographic impediment, he was in Victoria and I live in Queensland. However, a quick check on Google Maps found that he was only a five-minute drive around the corner, from my wife’s uncle Matt. Great news for me, but not so good for Matt.

Although Matt is my wife’s uncle, he is only a few years older than me, a great bloke, into cars, and, as I found out, extremely patient. I convinced Matt to check out the parts for me and pick them up if they were good. Matt only knows a little about rotaries, so it was more or less to suss out the bloke, make sure the stuff was there and pick up the bounty.

Matt phoned me later that day to inform me he had a bucket load of parts taking up valuable real estate in his garage; he didn’t know what he was looking at but hoped it was what I was after. After all the effort, I hoped I hadn’t bought a bunch of boat anchors too. Over the next few weeks, we chatted about the best freight options and how to pack and send them. Sending car parts can be expensive, and I got many different quotes.

 Hunting and gathering, all for a good cause.

The cheapest option was to get it all on a pallet and have it forked on and off a truck, or dropped at a depot. The only problem was Matt, like most people, didn’t have a forklift at his house. I was determined to get a good deal on the freight, or else all the work on finding cheap parts would be in vain, if the budget blew out on shipping. Matt, stuck with a garage full of parts, was also keen to see them relocated.

Matt is a crane driver by trade, so I think he enjoyed the challenge of getting all the parts on a truck without a forklift; I distinctly remember him saying something about rigging to me on the phone, with youthful exuberance.

Matt ‘acquired’ a box for the parts from work, which was big enough to be classified as a studio apartment in Melbourne. It was huge, but as Matt said, the price was right, and the size didn’t affect the shipping. As mentioned, Matt is not a rotary man, so he wasn’t sure about how fragile the parts were and dutifully packed them like the crown jewels. He loaded the box on to a ute with all the family helping. The package was well over 400kg and looked like it wouldn’t be out of place, propping up one of the great pyramids.

It needs ACME, on the box.

I shipped the box to a mate’s workshop with a forklift to unload it. He was also quite curious about all the bits and pieces in the box that form these little powerhouse engines. But he was also keen for me to come and relocate the parts out of his workshop as soon as possible; that’s the polite version of what he said.

The parts haul turned out to be a good buy; there were more housings than expected, and all the engine plates I needed were in good condition. A mate who built a few good rotaries over the years popped around and helped me separate the good parts from the bad. We put everything to one side that I needed for a complete build and had almost enough parts left over, for another engine. Included in the loot were all the clips, nuts and bolts, counter weights and all the other little bits and pieces you don’t think you need. Plus a set of headers, oil coolers and ignition system, coil packs, flywheels, and some end plates that looked like they’d been fished out of the ocean.

 Some rotaries for the project

The next step will be to clean all the parts, itemise and pack them up for the engine builder. As much as I’d like to have a go at building the engine myself, this is way too specialised of a job, and with engines few and far between, I’d rather it built right the first time.

This may seem like a long-winded story about getting some old parts shipped up from Victoria, and it probably is. But the reality of getting a project car on the road is always a much bigger exercise than expected and drags in all sorts of friends and family for the ride, whether they like it or not. By the time a restored or modified car gets on the road, a lot of people have helped along the way, who end up having a little vested interest in seeing your project come to life. 

This project is a fair way off completion, but with an engine sourced, I certainly feel some momentum building. Now to see who else I can drag along for some shed time.

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