The Staff of Motorsport Marketing
The Staff of Motorsport Marketing Writer
11/14/17 9:20 a.m.

Mike Allen
Mazdaspeed Motorsports Development
1421 Reynolds Ave.
Irvine, CA 92614
mazdamotorsports.com
(800) 435-2508

To avoid getting an RX-8 with a bad engine, it helps to know the history of the car. Check lemon law records, title history, and look at the warranty history to see if engines have been replaced. Telltale signs of a weak engine are oil smoke, overheating, and hard starting–especially once the engine is hot.

Before you buy, take it to a dealer to run a compression test. Any rotary engine needs a special compression gauge. The spark plug hole is going to give you the highest pressure of the three chambers, so you need a tool that will show the pressure in each chamber. Dealers have a special tool with digital readout that can do this.

These cars have perfect 50/50 weight distribution. That’s the big advantage of a rotary engine: It’s so compact, you can mount it very far back in the chassis. The rotary will run at high rpm and has good reliability when it’s taken care of.

When you go to a track, watch your oil consumption. Make sure the level stays full. Also keep an eye on your temperature. If you’re running in an area with high ambient temperatures, I recommend upgrading to a bigger radiator.

The metering oil pump delivers a small amount of crankcase oil into the intake to lubricate the apex seals and other components. It’s hard to fool that system in the RX-8 because it’s electronic. You can run the supply line to a separate reservoir if you want to run different oil in the metering system, or you can block off the feed completely and pre-mix oil with your fuel.

We duct the front brakes on our race cars, but I know a lot of guys who don’t. The car has really, really good brakes. If you have a street car that is on track only part-time, I’d just put good pads on it and call it a day.

Mazda made improvements throughout, but 2009 and up are the best years to buy. They improved the oil metering and the fuel-injection system to help reliability.

The 2004-’08 cars had an Aisin six-speed manual transmission, which is fine for street duty but not the best in a race environment. Mazda produced its own unit for 2009-and-up models, and it’s much stronger.

You can swap this transmission into older cars with minimal effort—just make sure it comes with its shifter. Everything bolts in, and they use the same driveshaft. The connectors on the reverse and neutral switches are different.

There’s not a lot of weight to take out unless you’re gutting the interior. The Sport model is probably the better one in terms of weight because you don’t get the sunroof or navigation.

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kevinh333
kevinh333 New Reader
11/14/17 10:33 a.m.

Great information; unless you have a second gen car (09-11) in which case most of the data does not apply, especially regarding springs which do not install from gen 1 to gen 2 with the same results in performance and ride-height.

If on the other-hand all you are looking for is "the look" or "stance", any lowering spring will work but if you want to truly enhance the already superb handling you are out of luck (if you own a second 2nd gen car).

Any recommendations?

fidelity101
fidelity101 UltraDork
11/14/17 10:34 a.m.

These are all great and accurate but you're missing two critical items. The ignition and starter these tend to give off a false sense of a bad engine. They usually just need coils/plugs/wires kind of tune up or a new starter. The 04-08 starters were a little weaker and if it doesn't crank fast enough combined with a weak spark you tended to flood to the engine which then people would assume it was blown. Great way to pick up a cheap rx8 this way. With the 09+ the stater improved with the transmission, more Kw and more teeth on the gear.

If you can't/don't want to take it to a dealer to get a proper compression test you can use a piston tester by holding the shader valve open and watch the pulses. best best is to use your phone to record it so you can avoid unnecessary excessive cranking.

A little clarification on the exhaust, there aren't a lot of gains with a full exhaust but the gain is weight loss, there is a big opportunity there because like mentioned above there is not a lot of places to cut weight out of this vehicle. For instance the stock driveshaft is carbon fiber! I would 100% back up the claim that the engine needs a lightweight flywheel - it really wakes up then.

I daily an S2 rx8 and I love it, I have a "short" commute so I don't mind the economy its all about the smiles per gallon! the suicide doors make it great for brief case storage and ease of access. If you can get a touring without a sunroof it gives you the HIDs and fog lights which are well worth it.

colinshark
colinshark New Reader
11/14/17 7:52 p.m.

I'm surprised this isn't mentioned, but I'm a fan of fuel-premixing on all rotaries. Particularly on the S1 RX-8s, it makes up for the stingy oil injection. I use a "sta-bil" bottle, which lets me measure the dosage pretty easily.

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