RX-8 with Mazdaspeed3/6 Motor Swap plan

[Chris B.]

For quite a few years I've had this plan to swap a Mazdaspeed3/Mazdaspeed6 engine into a RX-8. I've been researching the idea more lately as my next project car. I Thought the RX-8 was a fun car with more than enough interior room, but its lack of power, gas mileage worse than a half ton V8 pickup truck, and some issues with the engine's reliability made me now want to buy one. I found it interesting that most of the RX-8's I've seen at track days had reliability issues with the seals or gaskets inside the engine. Coolant in your oil and oil in your coolant were the typical end result. Also the car will probably get better gas mileage with the 2.3 turbo and Miata gearing than the RX-8 ever could.

The newer MX-5 Miatas and RX-8 share quite a few components. The subframe from the front of the MC miata might even bolt up to the RX-8. If it doesn't, that's nothing a little welding or custom brackets can't fix. The transmission from the NC Miata also fits in the RX-8 and they share the same rear differential.

I've looked on several Mazda and RX-8 related forums to see if anyone tried the swap and most of the threads asking about the possible swap resulted in the original posted being called a troll or replies stating that youa re better off swapping in an LS motor. Apparently the Rotary fanatics don't like the idea of a non rotory in an RX-8. As for the LS swap, I'd rather buy a Corvette than do an LS swap in an RX-8.

Most of the extra weight will be over the front wheels or behind the front wheels, so handling shouldn't be affected that much. The main issue I've thought of is the clearance for the hood. I think the 2.3 will stick up further toward the front of the car than the stock rotary motor does. Any of our Mazda experts have any other ideas about possible issues with the swap.