You Need This: Opel GT with Mazda BP inline-four power

While this Opel GT might resemble most other examples out in the world, opening the hood proves otherwise.

In place of the factory Opel inline-four? A 1.8-liter, Mazda BP inline-four–with a turbocharger added for good measure.

Gear changes are handled via a Mazda-sourced five-speed manual, and you’ll find a 3.70:1 rear differential from a Volvo out back.

Find this 1972 Opel GT Coupe available from Mecum’s Dallas/Fort Worth auction on October 30.

Comments

Keith Tanner GRM+ Memberand MegaDork
9/8/25 12:51 p.m.

Bill Cardell, the founder of Flyin' Miata, has been thinking about a swap like this for years. He even had a scrap Opel and a driving Opel to work with. The scrap car has been sold, I don't know if the project is still alive. But I'm going to share this with him!

Keith Tanner GRM+ Memberand MegaDork
9/8/25 12:54 p.m.

Those fenders are so stretched I'm wondering if there's a significant amount of Miata suspension under there as well.

Colin Wood Associate Editor
9/8/25 12:57 p.m.

In reply to Keith Tanner :

I wouldn't be surprised. All the listing mentions is "Koni adjustable shocks."

Keith Tanner GRM+ Memberand MegaDork
9/8/25 1:03 p.m.

Says it has a Volvo rear diff and 11" brakes. The latter is a common Miata big brake size.

Too bad it's not on BaT, because then we'd have a bunch of undercarriage shots!

SKJSS (formerly Klayfish) UltimaDork
9/8/25 1:49 p.m.

Absolutely beautiful!! I wonder what it'll sell for. Opel GT prices are all over the place.

Colin Wood Associate Editor
9/8/25 2:20 p.m.

Keith Tanner said:
Too bad it's not on BaT, because then we'd have a bunch of undercarriage shots!

I just did a quick Google search of the VIN from the listing, and it looks like it's previously been listed on Bring a Trailer.

https://bringatrailer.com/listing/1972-opel-gt-5/

Keith Tanner GRM+ Memberand MegaDork
9/8/25 2:36 p.m.

SNEAKY COLIN.

Rear mount turbo, that answers some questions I had. And definitely not Miata suspension. That's a well documented swap.

Rodan UberDork
9/8/25 2:38 p.m.

Many more pics on the BAT listing... the turbo is rear mounted, with a muffler before the turbo! Solid axle rear, and lots of fab work visible up front, but definitely not Miata suspension.

DWNSHFT Dork
9/8/25 2:39 p.m.

I like it! Especially the line of the front fender flares: unusual but good!

stuart in mn MegaDork
9/8/25 3:09 p.m.

Something I've always wondered about rear mount turbos is you have the air intake in what's probably the dirtiest, dustiest location on the car. You'd want to make sure there's a good filter, and that it gets changed often. And don't drive through any puddles of water.