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Hey all,

Well I've been planning on dropping a rotary in my project car, but I'm curious on what kind of performance numbers you could get out of a 1.9L... I'd prolly be looking at something that was mildly tuned for street and a little strip, possibly converted to fuel injection with something like a Haltech controller. I like the idea of fuel injected a little better due to cold weather starting, and tunability.

Also what kind of prices would it take to get it upgraded.

Thanks for the help


performance #´s

The performance numbers that I've found said that the 1970 Opel gt with the 1.9L engine was kicking out
102 hp w/ 115 lbs. of torque @3000rpm. I found these 3's at opelgtsource.com.


Ah yes, but those were the days of "gross" horsepower ratings, not SAE net ratings. A more accurate number for hp on a 1970 GT is 82-85 (at the flywheel). But this is easily increased to 100-110 "real" hp with the proper bolt-ons.

Going even further, and modifying an Opel to produce somewhere on the order of 140-150 hp will result in a car that is VERY quick, even by today's standards.

Achieving hp levels above this reliably either requires a much larger Opel engine (2.2 or 2.4) with extensive modifications, or the installation of "power adders" such as a turbocharger, supercharger, or nitrous oxide.

With a naturally aspirated engine, the upper limit will be around 200-220 hp for a 2.0 litre racing engine, or about 230-260 for a 2.2 to 2.5 litre racing engine. But with a turbo, a "mild" streetable 2.2 litre could make 275 to 325 hp for less money than a racing 2.0 litre naturally aspirated engine could be made.

But either way, it will not be cheap. For a 2.2 litre turbo with stand-alone FI and a new turbo/intercooler/fuel system, the price will be around $6000 or so, depending on how much work you do yourself. And the brakes, suspension, tires, transmission and rear axle will all need to be upgraded. Even a Getrag 5-speed 240 will not be adequate for a strong turbo, I've had quite a few fail with non-turbo 2.4/2.5 litre street engines because of the torque they make. Assume 200 hp to be the absolute hp cap for the Getrag, after that it's bye-bye!


Super Moderator
6,531 Posts
Yea, I was expecting to prep my GT for new rear brake shoes, but some Texan sniped them off eBay :eek:

Actually, I had a bit of minor surgery on Tuesday (bilateral inguinal hernia repairs) and although I can type and go for short walks, getting under the GT or SportWagon just seems a bit more than my sore tummy can stand.

But Trevor (aka Poffenroth) has invited me over after supper to see and hear his GT run with its new Weber. Ah, the joys of living my Opel restoration vicariously through others!
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