Selectmaz has new generation closed ratio gearboxes in 5 speed 1:1 top Synco with high quality Helicoil cut gears.

To find out more check out our specs below or phone/ email us and we can help with all your questions and requirements.  Just ask for Issy  ( Engineer)

Selectmaz offer a complete range of rebuilt standard gearboxes, covering the whole range of Mazda gearboxes ever made. We encourage clients to update to later model Mazda gearboxes rather then rebuilding, as some of the older gearboxes can be very expensive for an inferior result.

We also offer these close ratio gearboxes in kit form,  These consist of the Gear set, syncro's, bearings, and other items so you can install them into your current RX7 Ser 4 or 5 Turbo Box.  This is very useful if you live overseas and dont want to pay the price of shipping of a complete gearbox.  Contact us for details..

Here is a little look at what is available from Selectmaz:

For Circuit Racing, NA or Turbo Powered Engines

5 Speed 1 : 1  top gear  Syncro Engagement  


1: 2.420
2: 1.780
3: 1.340
4: 1.130
5: 1.000

RX7 5 speed, Series 4 or 5 close ratio gearboxes are fully rebuilt with new High Performance Bearings, new Helicoil cut gears, new Syncros, steel selector in place of aluminum, interlocks too stop selecting two gears at once, High Tension bolts, Clearancing and gear stick Modifications.

We have had great success with our race gearboxes both in Australia and overseas.  With events like Circuit racing, drag and hill climbs inc rally use and is highly recommended by some of the top overseas drivers.  With our highly reliable gearbox and low maintenance internals,  parts are easily obtained since we use genuine Mazda Syncros and parts, plus high performance bearing you won't have to be worrying when your gearbox is going to let you down,  also with lockout gearstick you wont have to worry about missing or selecting the wrong gear which can lead to over reving and expensive engine rebuilding.

We also offer our superior Race gearstick to suit our Race gearboxes which shorten the throw to quicken gear changes and have an incorporated lockout mechanism to lockout 1st and Reverse gears during the race, the lockout is push button operated and will automatically engage after shifting from 1st or reverse.  This lockout enables you to select all the other gears without the fear of accidentally selecting 1st or reverse during intense racing.  It is made from high quality Billet Alloy and Chrome Moly for smooth operating and reliability.

Options Available

  1. 1. 5 speed RX7 series 4 or 5 complete S/H Core gearbox
  2. 2. RX7 Turbo Starter Motor
  3. 3. Lightened steel flywheel (complete, and balanced with new ring gear)
  4. 4. Race clutch kit (Steel Billet, Heavy/Duty Pressure plate, fully balanced, High quality  puck clutch in either sprung or solid centres and thrust bearings)
  5. 5. Spigot Bearing & Seal (to suit RX7 Series 4 or 5, input shaft)
  6. 6. Rear Tail shaft Yoke to suit larger, main input shaft
  7. 7. Short shift kits
  8. 8. Selector Housing modifications to suit your vehicle needs
  9. 9. Hi Volume steel gearbox sump pans for extra oil and stronger gearbox reinforcement

The gearboxes are assembled by the Selectmaz technicians, with long time race experience, to guarantee reliable and a good quality product.

We also offer Rx7 turbo Ser 4/5 gearbox conversation to suit most Mazda Rotary vehicles,  Most applications are custom workshop and need the car here to do the conversation, but in the case of Mazda RX7 Ser 1,2 & 3 we can offer bolt in kits inc all the necessary parts needed for the job.  We only offer high quality Exedy and Mazda parts and cost depends on installation requirements and additional parts and labour needed or requested by the Customer. 

We also offer complete Clutch Kits and Drive train parts,  see our section on Clutch/Flywheels and also our range of Diff upgrade packages we offer.