When you attempt to do a non-OE engine swap in your parent’s garage, there’s a good chance that your story will end with “so we gave up and got it towed to a shop”. If you do manage to swap a Chevrolet engine into your Mazda with the help of a few buds, you’ll definitely make mistakes, mistakes that would leave engine-swap-aficionados slapping their foreheads in laughter. Naturally, those mistakes can have catastrophic consequences. And that is how I ended up on the side of Highway 403 with a broken car, clutching my CAA membership card.
Rewind to a little over one year ago, when we first put the 2.4-liter LE5 motor into the car. My friend Milan was busily tearing apart the Mazda’s factory engine bay while I started prepping our Chevy Ecotec engine for its new life in a Mazda Miata. That prep included swapping out the factory Chevrolet oil pan for an oil pan supplied by Ecotec Miata. Here’s where things went wrong: because the oil pan is a square and the engine block isn’t, you need to apply sealant to the engine, not to the oil pan. Apply sealant to the oil pan and there’s a good chance you won’t get a good seal around the oil pick-up hole.
This critical mistake became obvious when we first started the car and the oil on its dipstick was a frothy, bubbly mess. That’s when I made my second mistake; I drove it. Being impatient to get my car on the road, I drove it from MT Motorsport in Richmond Hill, back to my parent’s garage in Brampton where we pulled off the oil pan to reseal it. Video evidence of this questionable life choice above.
With the engine still in the car and the oil pan off, we weren’t able to apply sealant to the engine block, because, well, gravity, so we applied liberal amounts of RTV to the pan, bolted it on and hoped for the best.
From there, it was great for most of the season. we did a bunch of lapping at Toronto Motorsports Park, drove 14 hours to Gridlife Midwest and back; even let Mr. Dave Pratte rip some EcoTEC in the car on camera. The car was phenomenal. Torque throughout the powerband, quick steering, massive grip thanks to fat Hankook RS4 mounted on 15×9” Konig Dial-In wheels and quality suspension – it’s the kind of car that could shred the egos of Corvette and Mustang owners alike around shorter race tracks. And autocross events, torque and an open diff made it a hooligan. Sure, it had its issues, you can read about our eventful Gridlife trip here, but they’ve been mostly sorted out. That’s about the time when the motor decided to grenade itself. The full story about that day you can find on Drivermod.ca
I got the car towed to MT Motorsport, and we’ve made good progress getting the engine replaced. It took about two hours to get the engine bay stripped and the old motor out of the car. The way the swap kit is designed makes engine replacement a pinch – six bolts on the bellhousing and two nuts on each engine mount is all that holds the motor in the car.
With the motor out, we could start assessing the damage. There were metal shavings everywhere; the VVT solenoids were covered in bearing material and it took two hours, an ocean of water, and two cans of brake cleaner to get all the metal shavings out of the Ecotec Miata oil pan. From there, we started the process of stripping the old engine of its engine mounts, clutch, flywheel and flywheel adapter, and thermostat spacers – basically everything that comes in the Ecotec Miata swap kit.
Our new motor, a 2.4-liter LE5 engine out of a 2006 Chevy HHR, arrived. Not only does this new engine have forged connecting rods, (’06-’07 motors got forged rods, my old ’08 motor did not), but we were told that it has just 47,000-km on it. Despite that, to quote Matt from MT Motorsport, “it looked like it was dragged out to sea”. It was a giant mess of rust and corrosion but my skepticism ended when we pulled the valve cover off – internally, this is a seriously clean engine.
On that note, I pulled everything off – the old header, intake manifold, intake manifold, the fuel rail, basically everything connected to the engine except for the oil pan and valve cover, scrubbed it down and gave it coat of aluminum-coloured paint.
From there, we started prepping the new engine with the Ecotec Miata swap kit. The thermostat and all the required spacers were moved over, the clutch, flywheel and flywheel adapter were installed and most importantly, the old oil pan was installed properly.
I’m trying to think of this as an opportunity to start over. We have a fresh motor, I’m conducting the swap at MT Motorsport with their watchful eyes looking over my work, and well, Ecotec motors are cheap. My previous high-mileage motor cost me $340, this much cleaner engine was $750. Now, we just need to replace the obvious – the oil filter, spark plugs, etc, and get this new motor in the car, just in time for the season to end.
Nobody said project car life was easy.
Phillip Oliveira is a local track day junkie who spends his days running the Canadian car culture journal DriverMod, and his nights awake wondering if his Ecotec-swapped Miata will ever be finished. You can see more of his work at www.drivermod.ca