New dog box transmission replaces the much-loved PBS, with many parts compatible. Transmission works with rotaries and, with some modifications, Miatas as well

Part No. 0000-02-9001-EM
Price: $9,980

The PBS transmission was loved by GT and Production racers, with many still using it today. However, parts are scarce and new units are nearly impossible to find, so Mazda Motorsports commissioned EMCO Gears to build a new competition transmission. The result is now available from Mazda Motorsports.

Jesse Prather of Jesse Prather Motorsports used an early version of the new gearbox in his E Production RX-7 during the 2017 racing season. “Mazda Motorsports contracted EMCO to take the PBS transmission and bring it up to modern standards,” explains Prather. “That was the goal, and they knocked it out of the park. I was really blown away with the quality. It’s the nicest transmission I’ve worked with, and I’ve worked with a lot of dog-ring transmissions over the years. The precision of the shifting is unsurpassed. They did a great job of updating it and I can’t say enough good things about it. It was a critical component of my car to achieve a third-place finish in E Production at the 2017 [SCCA] Runoffs.”

While the EMCO Gears transmission is expected to find a home in many RX-7-based Production and GT cars, being an easy mate to a rotary engine, it can also be used in a Miata for GT or Production. Prather has converted the transmissions for use in Miatas, and is well versed in the process – which is not easy – so both he and Mazda Motorsports suggest that utilizing Jess Prather Motorsports (JPM) in the process is a good idea.

It starts with removing the bellhousing from the transmission and sending it along with a ’99-’05 (NB) stock Miata bellhousing to JPM. He says the NB bellhousing already has the proper holes to run the later-model starter, which is an improvement on older designs. The customer will also need to send along a competition throwout bearing from Mazda Motorsports, which JPM will modify.

“We will remove the rotary part of the bellhousing from the EMCO Gears transmission and weld an adapter plate between the two bellhousings to connect the front side of the Miata bellhousing to the EGMT,” Prather explains. “This is a very precise procedure to retain proper angle and alignment for the bellhousing to engine depth and input shaft alignment. After this procedure is completed, the customer can utilize the stock external slave cylinder and throwout arm from his Miata plus the JPM modified throw out bearing that the customer provided.”

There are several more steps that the customer, whether with his or her own fabrication skills or working with a local shop, will have to perform, including creating a transmission mount, removing the top of the transmission tunnel and making a new cover. JPM can provide details on the process, as well offering information about a shifter and linkage, which can be installed in a racer’s preferred location since it is no longer defined by the stock opening for the shift linkage.

For those who already have a PBS transmission, EMCO Gears is manufacturing replacement parts for the original PBS, many of which are cross compatible with the new transmission – that includes bearings, seals and spacers; drop gears; 1st motion shaft; input shaft; counter shaft; and tail shaft. Mazda Motorsports has also sourced some replacement parts for the PBS that are not compatible with the EMCO, such as dog rings made of upgraded materials and steel shift forks instead of the original brass pieces.

The Mazda Motorsports 5-Speed Transmission (by EMCO) will have a wide range of gear sets available, “From wide ratio to a narrow ratio to everything in between,” says Prather. “There’s going to be a much wider selection of ratios, not only in the gears, but the drop gears as well.”

EMCO has a long history of providing quality equipment to racers, the aerospace industry and many other applications. Prather’s enthusiasm for their latest creation for Mazda Motorsports indicates that they’ve achieved that goal again. “It’s a great addition to my race car and no doubt about it, a great addition to anybody’s race car.”

MazdaMotorsports.com has the following part compatible with the new 5-speed Mazda Motorsports transmission by EMCO and PBS:

Part #	Description	Feature/ benefit of EGMT upgrade	Racer Price
0000-02-9064	Tail Shaft	Material Upgrade /Extended Durability	$ 379.00

MazdaMotorsports.com has parts for the PBS that EMCO Gears manufactured (i.e. NOT the Mazda Motorsports transmission by EMCO Gears); they are:

Part #	Description	Feature/ benefit of EGMT upgrade	Racer Price
0000-02-9031	Shift Fork, Steel (1st/Rev)	Feature: Forks from brass to steel. Same design.   Benefit: Stronger Part with a longer lifespan	$    449.00
0000-02-9033	Shift Fork, Steel (4th/5th)	Feature: Forks from brass to steel.   Benefit: Stronger Part with a longer lifespan	$    449.00
0000-02-9035	Dog Rings	Material Upgrade /Extended Durability	$    205.00
0000-02-9061	Input Shaft	Material upgrade / Improved durability most noticed in the spline area	$   345.00
0000-02-9062	1st Motion Shaft	Material Upgrade /Extended Durability	$    449.00
0000-02-9063	Counter Shaft	Material Upgrade /Extended Durability	$    449.00
0000-02-9055	Coupler, 1st Motion Shaft	Material upgrade / Extended Durability	$    170.00

*****Please note, these parts above DO NOT work within the gearbox by EMCO. You may damage your gearbox if you do not adhere to these notes.

MazdaMotorsports.com has many parts manufactured by PBS, only for the PBS, in stock. Click the category below for a corresponding PDF/JPG (note, as racers purchase these parts, parts inventory levels will reduce until no longer in stock nor carried):

Bell Housing & Shift Mechanism: Diagram / Parts List with Quantities
Main Case & Tail Shaft Assembly: Diagram / Parts List with Quantities
Counter Shaft & Reverse Idler Assembly: Diagram / Parts List with Quantities
1st Motion Shaft Assembly: Diagram / Parts List with Quantities

AVAILABLE NOW: Replacement parts for all the parts in the Mazda Motorsports 5-speed transmission by EMCO.