Home / Modify Cars

One of the nice things about the net is it has helped shade-tree mechanics get together and share their knowledge and enjoyment of working on cars. I never would have attempted even basic things like bleeding brake fluid if it weren't for the help of others. Using the "pay if forward" concept I now try to help teach others how to do things like install shocks/springs or replace brake pads/rotors/calipers. The guides below are specific for that vehicle but the general principles apply to any car. Permission is given to redistribute individual DIYs without alteration provided you cite the original author and provide a link back to the original page.

2004 Mazda RX-8

• Battery replacement
  The original RX-8 battery had 305 cold cranking amps--totally inadequate and subsequently replaced with a 640 CCA model. If you have the original battery or just want a better designed battery, consider the Optima series.
• Brake rotor and pad replacement
  Replacing brake rotors and pads is pretty much the same regardless of which car you have. If you have never done it before this will show you how.
• Cabin air filter
  The stock cabin air filter is pretty flimsy. By contrast the aldehyde filter is much thicker and removes more odors.
• Cup holder insulation
  The cup holders in the RX-8 are notoriously known as cup warmers due to their proximity to the catalytic converter. Mazda issued a bulletin to add extra heat shielding but even that doesn't work. The stock fabric insulator doesn't do a very good job so I thought I'd try something else.
• Fluids: Tranny, Diff and Brake
  Regardless of OEM service intervals, I'd recommend changing all three once a year.
• Front and Rear Jack Points
  If you have a low profile jack it's possible to lift two wheels off the ground at once. This makes it easier to put jack stands under the regular jack points next to each wheel.
• Greddy turbo kit (stock airbox modification)
  There are two things about the Greddy turbo kit that I'm not wild about--the sponge air filter and the fact it's sitting exposed to the hot engine bay air. Since it's directly in front of the fresh air duct it isn't that bad when the car's moving but at slow speeds or idle it's sucking in lots of hot air. That can cause light engine pinging (aka detonation) which is never a good thing. Although enclosing the filter in the stock airbox restricts the air flow, most of that air will be cooler which is a good tradeoff.
• Mazdaspeed body parts
  Scanned images from the Japanese MazdaSpeed RX-8 body kit install instructions. Even without translation it's easy to follow the pictures and learn what's involved before buying the parts.
• Miscellaneous custom bits
  Various custom modifications that are too small to warrant a page of their own.
• Navigation firmware upgrade
  There are three software versions for '04-'05 Mazda navigation units (CN-VM4360A). The first was U9.95 2003.1. This update is the second one, U9.136 2003.7 released in 2003. Thanks to maverick02 of the RX8Club for providing this update. There is one final update I know of (U9.139 2004.1) released around June of 2004. If anyone has a copy I can host, please let me know.
• Replacement clutch part list
  Accurate as of 12/21/04, the part numbers and prices are for reference only.
• RX-8 Shop Manuals
  I forget where I first saw these manuals, but shortly after the RX-8 was introduced these were posted on the web. Some of the information is incomplete or outdated but it's a good starting reference for any project you want to tackle.
• Front Shocks
  The front shocks are very easy to replace. Once the car is on stands and the front wheels removed it's less than an hour's work to remove and replace them with an aftermarket set.
• Rear Shocks
  Unfortunately the rear shocks take more time to replace compared to the fronts.
• Moton Club Sport Coilovers
  If you are putting in a high-end set of coilovers that utilize a remote reservoir, these instructions will help you with that task. Also included are detailed assembly instructions for Moton Club Sport coilovers; something that Moton neglects to include with their product.
• Turbo Timer
  I used an HKS turbo timer with good results. Another person encountered difficulties (rough idle when the turbo timer is on) using an Apexi. I don't know why.
• Valentine1 hardwire and concealed display
  Free up your cigarette lighter and make the cabin look neater when you have a radar detector.