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As many of you are aware for a few years now I've been bitten by the rotary bug, they're not for everyone but I love 'em!

So quite some time ago I purchased myself a JC Cosmo with a factory 20B in it, I had the motor built by local rotary gurus 'Rotomotion' (GT4202R, dowelled, bridgeported etc.) and it made a bunch of power which was great. 2 years ago at RaceWars 2014 my tailshaft let go and I destoryed the back of my gearbox, since then the Cosmo has not been driven :( The Cosmo was in pretty poor condition and the dream ever since has been to buy an RX-8, drop the 20B in and go racing, good chassis + good engine should mean a fast car!

So last Saturday I finally got my hands on a car I wanted in my budget, picked up an un-registered RX-8 roller and thus my first proper motorsport build has begun!

As you can see I purchased the car with no engine or box so that is alread taken care of for me, I now have the car in the corner of the workshop and I'll probably start stripping it down soon.

RX-8.jpg

engine bay.jpg

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1 hour ago, r32-25t said:

I thought you were building a street car with it

Nope, un-rego'd shell.

Sure I might chuck the trade plates on it but ultimately I'd like to take it to the track.

Welcome to the RX8 family.

My daughter has had a Series II RX8 for the last two years and I have spent many hours during that period servicing and upgrading it.

Dimension wise it is very close to my R33 GTR in wheelbase and track. The front and rear brake disks are also the same size as the GTR.

They are a strange animal to drive with a 50/50 weight distribution compared to our nose heavy Skylines. Braking, turn in and mid corner grip is amazing it is just the lack of power to drive out of corners like a Skyline that they lack. The installation of a 20B would go a long way to fixing the lack of punch.

In the US there are a number of kits to install a LS series motor and box from the new Corvette into the RX8 - that really gives them some punch. The kits are that detailed that they run the Corvette ECU to run the engine and then splice all of the sensors back into the Mazda ECU to run the dash and all of the systems. A friend has done this conversion in a FD RX7 and it is that seamless of a conversion that it looks like it came that way from the factory.

Subscribed to your thread to follow your progress.

13 hours ago, Victory said:

Welcome to the RX8 family.

My daughter has had a Series II RX8 for the last two years and I have spent many hours during that period servicing and upgrading it.

Dimension wise it is very close to my R33 GTR in wheelbase and track. The front and rear brake disks are also the same size as the GTR.

They are a strange animal to drive with a 50/50 weight distribution compared to our nose heavy Skylines. Braking, turn in and mid corner grip is amazing it is just the lack of power to drive out of corners like a Skyline that they lack. The installation of a 20B would go a long way to fixing the lack of punch.

In the US there are a number of kits to install a LS series motor and box from the new Corvette into the RX8 - that really gives them some punch. The kits are that detailed that they run the Corvette ECU to run the engine and then splice all of the sensors back into the Mazda ECU to run the dash and all of the systems. A friend has done this conversion in a FD RX7 and it is that seamless of a conversion that it looks like it came that way from the factory.

Subscribed to your thread to follow your progress.

Thanks Charles, from the Gong as well!

One of the reasons I wanted the RX-8 was because it has a great chassis. It's a fair bit more modern in design than an FC or an FD (or say a Skyline), lots of available aftermarket parts as they were sold locally in Japan, Australia and the USA and it should be made to be really good around corners. A nice set of coilovers, swaybars, strut braces, underbody bracing and eventually a cage should make it turn on a dime.

Luckily for me I have the ECU, wiring and Microtech out of the Cosmo, between that and what's left in the RX-8 I don't imagine it will be too difficult (in the scheme of things) to get everything running nice. And putting a rotary into a car which already had a rotary in it obviously makes things a bit simpler again.

 

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