Any one know a reputable shop that will do a V8 conversion to a 91 Mazda Rx7 Turbo II in NV or CA.?

Question

I live in Reno NV I might drive to the Bay Area, But that's about my limit. I'm not really ready to do it yet but maybe in about a year or two. I'd like an LS1 or a ford 4.6 DOHC. Any info would be awsome. Thanks.

Answer 1

What you are proposing is a problem.

The Chevy Monza, circa 1973 was suppose to have a Wankel engine. But then the gas crisis hit and Chevy knew that the Wankel engine, which is a gas hog, would not be a selling point. Also the pollution standards were getting more strict and Chevy was not sure it could meet them with the Wankel engine. So they stuck in a little four cylinder engine as the base engine and a V8 for the upgrade engine. But they had a major problem. The power output shaft off a Wankel engine is at the center of the engine. On a conventional engine it is at the bottom of the engine. That made the engine swap pretty hard to do, specially for the V8 and that led to a number of problems.

1. To change the back two spark plugs you either had to lower the engine by undoing the motor mounts and using a jack to lower it OR you had to drill holes through two of the body panels in the engine compartment above those two spark plugs.

2. The car had a high center of gravity due to the elevated V8 engine. Instead of it being tucked nice and low like the Wankel, it sat high in the engine compartment.

3. The weight distribution was really bad. The original design was for an engine that weighted hundreds of pounds less. With so much weight in the front and quite a bit less in the rear, which were the drive wheels, you could smoke the tires very easily but more importantly, driving on snow or ice was very tricky with even the expansion joints on a concrete road being enough to break the traction.

4. They had to put in special metallic fiber brakes on the front to get the car to stop decently due to all the weight up front. You would go through 2 brake pads in the front for every 1 in the rear. And those front pads were NOT cheap.

5. Lastly, the gas mileage was no better than if they had stuck with the Wankel in the first place.

If you are keeping the car as a collector's car, you will ruin it with a V8. You will also create a ton of problems like the ones I mentioned above. Remember the location of the output shaft on the engine. That will take some major work to get the transmission to line up with the new V8 engine output shaft.

There are plenty of places to get a used engine in Reno and I think you could find another Wankel to put into the car.

I get my parts at Airport Auto and Truck Wrecking. [phone]

Answer 2

Stick with your 13b Rotary. They're perfect for the FC3S (your car), Just look at Ryosuke Takahashi, the fastest street racer in Initial D. A Rotary is compact and lightweight, while very powerful with proper tuning. While not as powerful as an LS1, it puts out more power per pound and that makes the car very agile when cornering.