3-Rotor Race Engine


Part Number: Engine
Retail Price: $48,000.00

3-Rotor Race Engine

Racing Beat currently has available for sale a very rare Peripherally Ported, Mazda Race 13G 3-Rotor engine in Racing Beat-engineered, single turbocharger configuration.

The engine is a complete Racing Beat built package producing more than 1000 bhp at 8500 RPM with approximately 21 pounds of boost. Designed to run on methanol, thereby eliminating the need for an intercooler, the race engine package incorporates an EFI Systems Engine Management System supported by a Kinsler Fuel Injection gear-rotor mechanical fuel injection pump. As prepared by Racing Beat, the engine features a complete Peterson Fluid Systems 4-stage oil scavenging assembly. Additionally, the engine utilizes an HPD water pump mounted to a Racing Beat-designed, cast aluminum front cover. These race-proven Kinsler, Peterson, and HPD components are all Gilmer belt-driven peripherals. The turbo charger selected for thes package is the AirResearch T18A90 series with the M-4 compressor wheel. As equipped by Racing Beat, the turbocharger features a TIAL Waste Gate modified to minimize boost spikes.

Internally, the engine includes the following features:

- All tension bolts fully "pinned"
- Water jacket modification on all rotor housings
- Iannetti Ceramic Apex Seals 3mm
- 7.5 to 1 Low-compression ratio rotors, cast by Mazda Japan
- Exhaust manifold - Inconel 625, including all bellows.

For more information or specifications, contact Racing Beat and ask for Jim Tanner at 714-779-8677.

This engine was produced around 1983/1984 for the 1984 LeMans 727c race car, and was used until about 1989.
The engine was based on the 13B engine of the time, with some special parts:
*Special centre housing with phasing gear
*Eccentric shaft to suit the 3 rotor design
*Different front housing (which has holes for the tension bolts to go through, as the tension bolts screw into the special centre housing).
*The rotor housings were the type with the water seal groove. (But, the external shape of the housings is narrower than the 13B)
*Most other parts, while virtually identical to the 13B, were custom-made for this engine

The eccentric shaft used was a new design not previously tried by Mazda. Previous designs were made from modified 2 rotor eccentric shafts joined together with bolts and keyways, which were not rigid enough for extended periods of reliable operation.
Essentially it was a 2 rotor shaft with a long extension on the front of it that went all the way to the front pulley. Then for the front rotor there is an eccentric shaft "sleeve" which slides over the front extension on the eccentric shaft until the angled section of the main eccentric shaft meets the corresponding section in the "sleeve" (Just like the flywheel does in any Mazda rotary).
The bearing/spacer/bolt down plate used to adjust the backlash (as in any Mazda rotary) performs the task of pushing the extension sleeve onto the tapered section.
The extension sleeve is indexed (so the rotor is in the correct phase with the other rotors) by a small keyway.

NOTE: There was also a 4 rotor engine very similar to this engine called the 13J
It was made a few years later that the 13G.

13G Racing Engine specifications Origin Based on early 80's 13B
Capacity 654cc x 3 rotors = 1962cc
Compression ratio 9.4:1
Induction Naturally aspirated peripheral port, electronic fuel injection (2 injectors per rotor)
Exhaust Peripheral Exhaust Port
Ignition Distributorless CDI ignition (2 plugs/rotor)
Power/RPM 450ps@8500rpm
Torque/RPM 40kgm@8000rpm
Max RPM 9500 RPM (Optimum 6000-9000rpm)
Dimensions Length 675mm Width 549mm Height 520mm (Complete engine)
Weight 143kg (Complete engine)
Special Features Dry Sump