4 rotor 12a
09-23-02, 03:18 PM
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4 rotor 12a
Autotech in San Diego just finish building their 4 rotor 12a. It will be going in an fd pretty soon. What do you guys think? Will it fit? (I think so) Same length as their 20B engine which they have in their shop car.
Last edited by spooled7; 09-23-02 at 03:21 PM.
09-23-02, 11:07 PM
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Originally posted by RX-Heven
Bastards! What is the projected power output? Can't wait to see that and all the other goodiees this weekend in SoCal.
Bastards! What is the projected power output? Can't wait to see that and all the other goodiees this weekend in SoCal.
mike
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09-24-02, 08:14 AM
#8
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I dont know if I should be scared or jealous.
But if the E shaft is made from anything less than titanium it may flex too much IMO.
09-24-02, 07:10 PM
#9
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a single t72 with 4 rotors!!! It'll spool faster than topfueler can burn out! With 12lbs of boost that will rule royal ***!!!!
ALL HAIL THE 24A!!!!!! an easy 700Hp!
ALL HAIL THE 24A!!!!!! an easy 700Hp!
09-26-02, 10:04 AM
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Originally posted by spooled7
They will be running it with a t72 @12lbs
They will be running it with a t72 @12lbs
09-26-02, 01:16 PM
#15
I could probably tell you. The 12A isn't 1200CCs. It's actually 1146 or something (peejay will know the correct amount; all I know is 13B stuff which is 654CC x 2 = 1308). The 10A wasn't 1.0liter either. Anyway, 23A is more accurate. But even the 'A' should have been a 'B' since it's based on the engine that came out in '74. I guess since it had the same displacment as the original 12A, they kept the same name. Hmm, a 13G has the same displacement as a 20B... 
09-26-02, 03:32 PM
#16
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Yes, it's 1146.
The 10A was actually 984cc. Each 10mm of rotor housing makes for 162cc on a 2-rotor engine. Stretch a 10A's rotor housings by 10mm and you get a 1146cc engine, stretch a 12A's rotor housings by 10mm and you get 1308cc. Add another 10mm and you'd get the 1470cc "15A" that never left the engineering department before Mazda canned the engine due to fuel economy concerns (think oil crisis).
I really wish Mazda did change the name to 12B in 1974. Would have made life a lot easier. No need to differentiate between pre-'73 and '74-up 12As (which are muchly different in every way). It also makes it confusing that the 12A and 13B are the same engine (just stretched) while the 12A and 13A share nothing.
The should have also called the '86-up engines 13Cs, since just about the only thing carried over was the gear that drives the CAS and OMP shaft!
Anyway back to the 23A... Mazda made a whole slew of engineering models in the 60's, singe rotors, four rotors, three rotors, etc. I do know that they made some engines based on 12A geometry (the 6A single-rotor at least) and they might already have made a "23A".
As for the 20B... Yep. You'd think that it should be called the 20A (first engine of its eccentricity/width/number of rotors) but it's the second one so therefore it's the 20B. The first one was the 13G. (Just like the R26B was the second of its type, the first being the 13J) NOW... why the hell did Mazda call the 3-rotor and 4-rotor engines based on 13B dimensions, the 13G and 13J? THAT is the tough question... just more proof that their system isn't much of a system
The 10A was actually 984cc. Each 10mm of rotor housing makes for 162cc on a 2-rotor engine. Stretch a 10A's rotor housings by 10mm and you get a 1146cc engine, stretch a 12A's rotor housings by 10mm and you get 1308cc. Add another 10mm and you'd get the 1470cc "15A" that never left the engineering department before Mazda canned the engine due to fuel economy concerns (think oil crisis).
I really wish Mazda did change the name to 12B in 1974. Would have made life a lot easier. No need to differentiate between pre-'73 and '74-up 12As (which are muchly different in every way). It also makes it confusing that the 12A and 13B are the same engine (just stretched) while the 12A and 13A share nothing.
The should have also called the '86-up engines 13Cs, since just about the only thing carried over was the gear that drives the CAS and OMP shaft!
Anyway back to the 23A... Mazda made a whole slew of engineering models in the 60's, singe rotors, four rotors, three rotors, etc. I do know that they made some engines based on 12A geometry (the 6A single-rotor at least) and they might already have made a "23A".
As for the 20B... Yep. You'd think that it should be called the 20A (first engine of its eccentricity/width/number of rotors) but it's the second one so therefore it's the 20B. The first one was the 13G. (Just like the R26B was the second of its type, the first being the 13J) NOW... why the hell did Mazda call the 3-rotor and 4-rotor engines based on 13B dimensions, the 13G and 13J? THAT is the tough question... just more proof that their system isn't much of a system
09-26-02, 04:34 PM
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Originally posted by peejay
why the hell did Mazda call the 3-rotor and 4-rotor engines based on 13B dimensions, the 13G and 13J? THAT is the tough question... just more proof that their system isn't much of a system
why the hell did Mazda call the 3-rotor and 4-rotor engines based on 13B dimensions, the 13G and 13J? THAT is the tough question... just more proof that their system isn't much of a system
mike
09-26-02, 05:40 PM
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Originally posted by peejay
NOW... why the hell did Mazda call the 3-rotor and 4-rotor engines based on 13B dimensions, the 13G and 13J? THAT is the tough question... just more proof that their system isn't much of a system
NOW... why the hell did Mazda call the 3-rotor and 4-rotor engines based on 13B dimensions, the 13G and 13J? THAT is the tough question... just more proof that their system isn't much of a system
09-26-02, 07:58 PM
#20
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Originally posted by Evil Aviator
I believe that the system uses the alpha to describe the seal type.
I believe that the system uses the alpha to describe the seal type.
Pre-73 12As use 1-piece carbon-aluminum 6mm apex seals and two sets of side seals. '74-85 12As use 2-piece iron 3mm apex seals and one set of side seals. Both are "A"s. (We normally differentiate the 12As by calling them "twin dizzy" or "single dizzy")
The 13A is similar is configuration to the 10A/early 12A in the way the seals are arranged. However, it's the only production Mazda rotary to have different trochoid dimensions from what the 10A started. It has 60mm wide rotors like the 12A but it has larger eccentricity (a "longer stroke"). This was to keep the engine as short as possible, because the R-130 Luce was front wheel drive.
'74-85 13Bs are completely different from 13As. They are functionally identical to '74-85 12As except for rotor width - they use the 10A/12A eccentricity, they use the '74-85 12A's sealing system of 2-piece iron 3mm apex seals and one set of side seals. They are, in effect, stretched '74-up 12As.
'86-up 13Bs use 3-piece iron 2mm apex seals and have different coolant seal placement AND different housing geometry. Yet they still use the same name as the earlier "B".
To avoid all of the confusion, Mazda should have called the '74-up 1146cc engine a 12B like they planned, and called the '86-up engines "C" engines. That way all twin-distributior, fat-sealed engines are "A"s (10A/12A), all single-dizzy, 3mm seal engines are "B"s (12B/13B), and all relocated water seal, 2mm apex seal engines are "C"s (13C).
But NOOOOOOOOOOOOooo.
09-30-02, 01:18 PM
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Originally posted by peejay
It has 60mm wide rotors like the 12A but it has larger eccentricity (a "longer stroke"). This was to keep the engine as short as possible, because the R-130 Luce was front wheel drive.
It has 60mm wide rotors like the 12A but it has larger eccentricity (a "longer stroke"). This was to keep the engine as short as possible, because the R-130 Luce was front wheel drive.
mike
09-30-02, 05:24 PM
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i doubt it, maybe by accident. they were all busy taking pics of fd's, casue nobodys ever seen a montego blue with tan one before.....
and i'm dumb enough to let everyone else take pics for me....
mike
and i'm dumb enough to let everyone else take pics for me....
mike
10-02-02, 11:42 AM
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there ya go peejay
mike