Why 12a in 1st Gen RX-7?
Thread Starter
I read your email
Joined: Jan 2002
Posts: 2,624
Likes: 1
From: NW New Jersey
I have to agree, gas milage seems to be the only reasonable explaination to me. At the time, gas mileage was a BIG deal. Every mpg counted.
Reliablility of the 12a over a 13b is also not a valid reason. Let's face it, at the time, the technology between the two engines was or could have been exactly the same. If they could make a 12a reliable then they could make the 13b reliable. Reliablitly issues with the 13b became an issue when they started turbo charging them years later.
Reliablility of the 12a over a 13b is also not a valid reason. Let's face it, at the time, the technology between the two engines was or could have been exactly the same. If they could make a 12a reliable then they could make the 13b reliable. Reliablitly issues with the 13b became an issue when they started turbo charging them years later.
root
Joined: Mar 2001
Posts: 1,200
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From: Phoenix, AZ
Ok, i didn't read all the crap above.. But i have like 3 RX-7 books, and ALL of them say it was for fuel economy.. The 12A was enough power to be competitive, and got better gas mileage.
At the time there was alot of trouble with emmisions & oil in the world. Well, the 2nd gen RX-7 almost never made it because of the gas guzzler tax.. Luckly we ended up with a better 2nd gen becuase of it.. (They lightend it, ie alot of aluminuim.. hell even the jack is aluminuim...)
-Zach
At the time there was alot of trouble with emmisions & oil in the world. Well, the 2nd gen RX-7 almost never made it because of the gas guzzler tax.. Luckly we ended up with a better 2nd gen becuase of it.. (They lightend it, ie alot of aluminuim.. hell even the jack is aluminuim...)
-Zach
Hunting Skylines
Joined: Apr 2001
Posts: 3,431
Likes: 4
From: Brisbane, Queensland, Australia.
I think it's a combination of some of the above. 
The 13B was previously only used in the Rx-4 and Rx-5 which were bigger, heavier cars then the 1st gen. Rx-7. Mazda felt that the 12A (which had been so heavily revised it probably should have been called the 12B) would provide ample preformance. When combined with the possible cost, fuel economy and weight issues Mazda probably decided there was no justification in going with the larger engine.
The 13B was previously only used in the Rx-4 and Rx-5 which were bigger, heavier cars then the 1st gen. Rx-7. Mazda felt that the 12A (which had been so heavily revised it probably should have been called the 12B) would provide ample preformance. When combined with the possible cost, fuel economy and weight issues Mazda probably decided there was no justification in going with the larger engine.
Senior Member
Joined: Feb 2001
Posts: 309
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From: n/a
Originally posted by MikeLMR
also my car and many others outside the states have a rear seat (as they were designed to have from the outset) so what did they add to the back of the US models to balance it all out ? ?
also my car and many others outside the states have a rear seat (as they were designed to have from the outset) so what did they add to the back of the US models to balance it all out ? ?
Joined: Jul 2002
Posts: 7,301
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From: District of Columbia
as far as the weight thing goes all the weight your talking about is between the front and rear axel so its very very evenly distributed. thats why rexys have near 50/50 distribution cause the engine sits behing the front axel not over it like 98% of all other cars
