Post any good 20b+ pictures
10-17-2002, 05:21 AM
#16
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Join Date: Nov 2001
Posts: 574
This is the 13J-MM
These 4 rotor pictures are from Craigs Rotary Page
http://cp_www.tripod.com/rotary/index.htm
This engine was produced around 1988 and used until about 1990 when it was replaced by the R26B.
It was based on the 13G 3 rotor engine, which in turn was based on the 13B (2 rotor engine) of the time, with some special parts:
*Special centre housing with phasing gear
*Eccentric shaft to suit the 4 rotor design (see diagram above).
*13J engine has 4 bearings (in the front housing, the first and third intermediate housings and the rear housing). Unlike the 2002 engine with only 3 bearings for the eccentric shaft (quite acceptable for a road car, but undesirable in a racing engine).
*Most other parts, while virtually identical to the 13B, were custom-made for this engine (The only common parts with 13G/13B were the rotors and rotor housings)
There were several revisions of the basic engine design, with minor improvements each time:
13J-M
(M = modified). 500bhp@8500rpm Peripheral port with fixed length intake trumpets, EFI, 2 plugs/rotor. Used in the 1988 LeMans 767 racer.
13J-MM
630bhp@9000rpm Peripheral port intake with variable length intake trumpets (2 steps only), EFI, 2 plugs/rotor. The 13J-MM has ceramic apex seals and the side housings were hot sprayed with a ceramic surface for wear&friction resistance. Used in the 1989 LeMans 767B racer.
These 4 rotor pictures are from Craigs Rotary Page
http://cp_www.tripod.com/rotary/index.htm
This engine was produced around 1988 and used until about 1990 when it was replaced by the R26B.
It was based on the 13G 3 rotor engine, which in turn was based on the 13B (2 rotor engine) of the time, with some special parts:
*Special centre housing with phasing gear
*Eccentric shaft to suit the 4 rotor design (see diagram above).
*13J engine has 4 bearings (in the front housing, the first and third intermediate housings and the rear housing). Unlike the 2002 engine with only 3 bearings for the eccentric shaft (quite acceptable for a road car, but undesirable in a racing engine).
*Most other parts, while virtually identical to the 13B, were custom-made for this engine (The only common parts with 13G/13B were the rotors and rotor housings)
There were several revisions of the basic engine design, with minor improvements each time:
13J-M
(M = modified). 500bhp@8500rpm Peripheral port with fixed length intake trumpets, EFI, 2 plugs/rotor. Used in the 1988 LeMans 767 racer.
13J-MM
630bhp@9000rpm Peripheral port intake with variable length intake trumpets (2 steps only), EFI, 2 plugs/rotor. The 13J-MM has ceramic apex seals and the side housings were hot sprayed with a ceramic surface for wear&friction resistance. Used in the 1989 LeMans 767B racer.
10-17-2002, 05:23 AM
#17
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Join Date: Nov 2001
Posts: 574
The 3805 4 rotor engine was one of the early prototypes. Produced in 1963 it was a relative of the early families of rotary that would develop into the production 10A engines.
The 3805 was derived from the L8A engine (0353), which also had a 3 rotor variant, the 3804.
The 3805 was tested in a prototype sports car (designated R16A, by 400cc rotor displacement x 4 rotors = 1600cc, or "16").
The target power output was 160hp @ 7000rpm, phenomenal for a mid 1960s Japanese car, however there was no test results to prove this.
The 3805 was derived from the L8A engine (0353), which also had a 3 rotor variant, the 3804.
The 3805 was tested in a prototype sports car (designated R16A, by 400cc rotor displacement x 4 rotors = 1600cc, or "16").
The target power output was 160hp @ 7000rpm, phenomenal for a mid 1960s Japanese car, however there was no test results to prove this.
10-17-2002, 05:25 AM
#18
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Thread Starter
Join Date: Nov 2001
Posts: 574
The 2002 was essentially two 10A motors joined together using a 'Curvic Coupling'.
It was produced in September 1971 which would imply being the type of 10A used in the R100 coupe. Power output was measured at 180hp@6000 rpm, with the engine capacity being twice that of a 10A (491cc x 4 rotors=1964cc), while the 10A of the time was making around 100hp, the 2002 was intended for a flagship sedan.
This engine would have been reasonably practical to manufacture due to the only special parts being the eccentric shaft made from modified stock 10A parts and the centre housing in the middle of the engine (which was wider to accommodate the coupling components of the eccentric shaft).
The main problem with the early forms of eccentric shaft coupling was that the were not sufficiently rigid to cope with continuous operation engine, as they were essentially two shafts with a spline to transmit the power and a bolt through the centre to hold the assembly together.
This problem was rectified in later multi rotor engines by having a single rigid shaft through the whole engine, with the rotor bearing lobes for the rear rotors as part of the shaft and the front rotor(s) using rotor lobes as an "auxiliary shaft" that slips over the top of the main shaft. See below for an explaination diagram, also see my 13G or 20B pages for a picture of this.
It was produced in September 1971 which would imply being the type of 10A used in the R100 coupe. Power output was measured at 180hp@6000 rpm, with the engine capacity being twice that of a 10A (491cc x 4 rotors=1964cc), while the 10A of the time was making around 100hp, the 2002 was intended for a flagship sedan.
This engine would have been reasonably practical to manufacture due to the only special parts being the eccentric shaft made from modified stock 10A parts and the centre housing in the middle of the engine (which was wider to accommodate the coupling components of the eccentric shaft).
The main problem with the early forms of eccentric shaft coupling was that the were not sufficiently rigid to cope with continuous operation engine, as they were essentially two shafts with a spline to transmit the power and a bolt through the centre to hold the assembly together.
This problem was rectified in later multi rotor engines by having a single rigid shaft through the whole engine, with the rotor bearing lobes for the rear rotors as part of the shaft and the front rotor(s) using rotor lobes as an "auxiliary shaft" that slips over the top of the main shaft. See below for an explaination diagram, also see my 13G or 20B pages for a picture of this.
10-17-2002, 05:29 AM
#20
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Thread Starter
Join Date: Nov 2001
Posts: 574
The R26B four rotor engine was developed for Mazda's racing program in 1990.
It was an all new design derived from the 13J engine (specifically the 13J-MM), but with few interchangeable parts.
The major differences from the 13J are:
* Three spark plugs per rotor-The additional one at the top is called a "late trailing".
* The variable length intake trumpets were multi-step in the 1990 R26B, continuously variable in the 1991 version (for maximum possible torque at any RPM).
* The rotor housings and side housings were hot-ceramic coated
The LeMan's specification engine produces 700bhp@9000rpm, 607Nm/448ftlb@6500rpm, and engine capacity is 654cc x 4 rotors=2616cc
The Mazda LeMans 787B racer powered by this engine won LeMans in 1991, the making both the first Japanese manufacturer and the first non-piston engine to win.
Acceleration of the 787B is impressive, as it weighs 800kg, giving it a power to weight ratio of 1.2kg/bhp (2.6lb/bhp).
As a comparison consider the following: Ferrari F40 2.6kg/bhp (5.7lb/bhp), Porsche 911 turbo 4.5kg/bhp (9.9lb/bhp)
This will allow a 0-100m (328ft) sprint in ~2.5 seconds, and a 1/4 mile with a terminal speed of 250km/h (155mph) - somewhere around 9 seconds!
(actually maybe about 10 or 11, as the car is not set up for drag racing)
Unfortunately the rotary was banned from European racing by FISA in 1992.
To a certain extent the USA's IMSA GTP series is very similar to LeMans style racing and the RX-792P carried the rotary flag for a while.
The R26B used in this car was down a little in power and torque, 650bhp@8500rpm, 570Nm/420ftlb@6500rpm
It was an all new design derived from the 13J engine (specifically the 13J-MM), but with few interchangeable parts.
The major differences from the 13J are:
* Three spark plugs per rotor-The additional one at the top is called a "late trailing".
* The variable length intake trumpets were multi-step in the 1990 R26B, continuously variable in the 1991 version (for maximum possible torque at any RPM).
* The rotor housings and side housings were hot-ceramic coated
The LeMan's specification engine produces 700bhp@9000rpm, 607Nm/448ftlb@6500rpm, and engine capacity is 654cc x 4 rotors=2616cc
The Mazda LeMans 787B racer powered by this engine won LeMans in 1991, the making both the first Japanese manufacturer and the first non-piston engine to win.
Acceleration of the 787B is impressive, as it weighs 800kg, giving it a power to weight ratio of 1.2kg/bhp (2.6lb/bhp).
As a comparison consider the following: Ferrari F40 2.6kg/bhp (5.7lb/bhp), Porsche 911 turbo 4.5kg/bhp (9.9lb/bhp)
This will allow a 0-100m (328ft) sprint in ~2.5 seconds, and a 1/4 mile with a terminal speed of 250km/h (155mph) - somewhere around 9 seconds!
(actually maybe about 10 or 11, as the car is not set up for drag racing)
Unfortunately the rotary was banned from European racing by FISA in 1992.
To a certain extent the USA's IMSA GTP series is very similar to LeMans style racing and the RX-792P carried the rotary flag for a while.
The R26B used in this car was down a little in power and torque, 650bhp@8500rpm, 570Nm/420ftlb@6500rpm