Rotary Project: 1974 Mazda REPU

Disclosure: This site may receive compensation from some link clicks and purchases.

This, to me, is one of the coolest pickup trucks ever built. The Mazda Rotary pickup remains, to this day, the only rotary-engined truck ever built and it has developed a loyal following because of it. However, they come up for sale quite infrequently and are definitely a labor of love if you wish to try and revive one from project-grade condition. The REPU shown here on Facebook Marketplace is a bit of a mixed bag as it’s clearly still a project and has had some money thrown at it in questionable ways. The seller reports the 13B engine is freshly rebuilt and hasn’t been driven, and he’s asking $25,000 for the quirky Mazda.

Thanks to Barn Finds reader PRA4SNW for the find. First of all, I completely dig this little ripper, so please take any criticism as purely constructive, dear seller. The value in REPUs tends to be in well-preserved examples or lovingly restored trucks, and this specimen appears to be neither. This is one of those vehicles I would recommend never modifying should you be lucky enough to find one, and the seller has chosen to incorporate a few non-standard tweaks. The respray is the obvious one, as this was not likely a standard Mazda color, and it’s been lowered on GMC wheels. Interesting choices, those.

It looks like the truck used to be red, and I would return it to that shade ASAP. The so-called recently rebuilt engine features a “…Holley 650 double pumper, 2 MSD boxes, full custom exhaust, and Racing Beat headers,” among other modifications. The upgrades will either leave you excited or scratching your head depending on your views of the potential of the rotary engine. I’ve always felt these engines are quite fussy and that mostly stock condition is the way to go, unless you’re solving for some well-documented oil consumption issues. The engine bay also looks like it could use some tidying up by the next owner.

The interior obviously requires complete restoration, with the exception of perhaps the bench seat. It looks like the original door panels and carpeting are long gone, and the aftermarket steering wheel should be expunged whenever the interior refresh takes place (the wood trim, believe it or not, appears to be factory). The seller reports that the REPU has been sitting for 8 years, which is unusual for a truck with a recently rebuilt engine. It will also need a fuel pump and starter before you even attempt to run it on the streets, so there’s a few weekends’ of work before the rotary rips once again. With 110 horsepower and surprisingly quick acceleration times, it’s a truck worth finishing, but $25K seems like a steep ask for a project when completely turnkey REPUs are selling reliably for $30,000.

Auctions Ending Soon

Comments

  1. Rw

    25k🥃😂 somebody Drankin…

    Like 11
  2. Big C

    For $25k? Pull that rotary, put in a nice V8 Ford. Add in a new interior, and leave some gold in the glove box.

    Like 8
  3. Daniel Harris

    2500 is more like it!

    Like 12
  4. Howard A Howard AMember

    I wholeheartedly agree, Mazda had the best styling then. I thought the RX4 was the nicest of all Asian cars, almost traded my MGB on one, thankfully, a test drive convinced me otherwise. Rotaries were a flash in the pan, a different, more complicated way of doing the same thing as a reciprocating engine. They didn’t like the cold, and got poor mileage and used oil off the lot. A huge cloud of smoke on the test drive the salesperson assured me was “normal” didn’t seem “normal” to me. While some success with the RX7, the rotary quietly faded away,,,until just now! I read Mazda brought back the rotary in a pickup again, only there’s a catch. It’s an EV and the rotary strictly only powers the generator,,boo, hisss,, well, there you have it, old what’s his name, Felix, spinning in his grave. I too say yank the “Spinny Thing”, and replace it with any number of piston engines, and for heavens sake, do something with that interior, jeez,, cool trucks, these people are nuts.

    Like 6
    • SubGothius

      Wankel rotaries are indeed a different way of doing the same thing as a reciprocating engine, but I’d hardly call them “more complicated”. The only thing maybe “complicated” about them is wrapping our piston-head brains around how they work.

      They have only a fraction of the total parts count of a comparable piston engine, and vastly fewer moving parts — just the two rotors and the output shaft. That’s it. Arguably the apex seals might also be considered “moving” (albeit infinitesimally), so add 3 of those per rotor.

      All that said, it’s a poor choice for a pickup truck, practically speaking. No low-end torque for cargo hauling or towing, high-strung and needs to be wound out to high RPM for maximum power output.

      Like 5
      • Howard A Howard AMember

        Thanks, and appreciate the obvious passion, and to clarify, complicated didn’t mean the number of moving parts, to “Joe belch a Pabst”, he couldn’t tell the front from the back and has no idea how many parts in a piston engine anyways. It was a gamble that had been tried before, air cooled, diesels, that whole EV thing, and in the end, new cars are still using that same technology of 125 years ago, albeit, highly refined. The rotary had mighty big shoes to fill, now reduced to turning a generator, that must be a kick in the bum.

        Like 0
      • JMB#7

        Actually compared to the four cylinder trucks it competed with the low end torque was good and delivered very smoothly. Have you ever driven one of these in stock form? This one might be a different story since the seller claims “large street port”.

        Like 0
  5. Tim

    How to spoil a very special ride.

    Like 2
  6. JMB#7

    45 years is a long “flash in the pan”. And now they are back as range extenders. {{Mazda’s primary production of Wankel rotary engines for mainstream vehicles spanned from the 1967 Cosmo Sport to the end of the RX-8 in 2012, with a significant break in traditional sports car production after 2012, though the engine was revived in 2023 as a range extender for the MX-30 R-EV. Key models include the Cosmo (1967-1995), RX-7 (1978-2002), and RX-8 (2003-2012).}}

    Like 3
  7. JMB#7

    Would love to have a REPU with appropriate modifications. While the owner had the right idea, this one isn’t worth the asking price. Refer to Racing Beat website…. Holly 650 CFM is a recommended option for a Bridge Port motor. The engine shown in the pictures doesn’t look “freshly rebuilt” but who knows (only the guy who did the work maybe)? Putting GMC wheels on a REPU is a sin in my book. IMHO, keep the rotary in it.

    Like 1
  8. PRA4SNW PRA4SNWMember

    When I first saw this listing, I thought “what a unicorn”. This deserves to be restored, but I agree that the asking price is too high of a starting point.

    I can see why most comments are going to be aimed at this being a piece of junk with a crap engine, but just like old rusty Chargers, there is an enthusiastic audience for these and this project needs to be completed.

    Jeff, I agree that this should go back to it’s original color, but the blue it is now is very close to what I remember our ’74 RX-4 “Rotary Wagon” being.

    Like 1
  9. Jake Crowley

    I’ll take a Toyota pickup instead with a good old 22R 4 cylinder piston engine, thank you very much! I addition to poor reliability, I don’t think rotary engine make much torque (which is what you need in a truck).

    Like 0

Leave A Comment

RULES: No profanity, politics, or personal attacks.

Become a member to add images to your comments.

*

Barn Finds