Swap Options?
Thread Starter
Senior Member
Joined: Sep 2007
Posts: 342
Likes: 0
From: Ontario, Canada
Swap Options?
so by now you all have heard i have a 73 RX-3 wagon with the original 12a. i would like to have something a bit more reliable engine wise. so i have been wondering what if any of the early frontmount 13b's would bold up to stock mounts? if anyone has any suggestions i would love to hear them.
Junior Member
Joined: Apr 2007
Posts: 16
Likes: 0
From: Ventura, Calif.
A 13b is more reliable than a 12a? Is that because the rotor housings are slightly wider which prevents the rotors from spinning out sideways? Kind of like why a fat person doesn't drown as easily as a skinny one?
Me thinks, if you want reliability, a Volkswagen boxer or Mercedes 240D engine is the way to go!
Me thinks, if you want reliability, a Volkswagen boxer or Mercedes 240D engine is the way to go!
I need a new user title
Joined: Oct 2005
Posts: 2,646
Likes: 1
From: Yaizu, Japan
You'll have to slot the holes in the front cover brace and crossmember so the front of the engine can be 20mm further forward, but other than that you should be good to go. Or you could get a '74 or later 12A, preferably first-gen RX-7 style.
I need a new user title
Joined: Oct 2005
Posts: 2,646
Likes: 1
From: Yaizu, Japan
A 13b is more reliable than a 12a? Is that because the rotor housings are slightly wider which prevents the rotors from spinning out sideways? Kind of like why a fat person doesn't drown as easily as a skinny one?
Me thinks, if you want reliability, a Volkswagen boxer or Mercedes 240D engine is the way to go!
Me thinks, if you want reliability, a Volkswagen boxer or Mercedes 240D engine is the way to go!
Thread Starter
Senior Member
Joined: Sep 2007
Posts: 342
Likes: 0
From: Ontario, Canada
A 13b is more reliable than a 12a? Is that because the rotor housings are slightly wider which prevents the rotors from spinning out sideways? Kind of like why a fat person doesn't drown as easily as a skinny one?
Me thinks, if you want reliability, a Volkswagen boxer or Mercedes 240D engine is the way to go!
Me thinks, if you want reliability, a Volkswagen boxer or Mercedes 240D engine is the way to go!
HEAVY METAL THUNDER
Joined: Oct 2002
Posts: 3,864
Likes: 0
From: Elsenborn, Belgian Eifel
No serious, there's something true about the 13B not being any more reliable than a 12A of course. If you want more power, 13B is an option, but if you want a reliable yet close to original engine, why not go 12A from a first gen RX-7? At least you can make it look "stock" than.
Trending Topics
I need a new user title
Joined: Oct 2005
Posts: 2,646
Likes: 1
From: Yaizu, Japan
Actually, anything made '74 or later is going to be more reliable due to all the changes Mazda made in that year (most notably 3mm apex seals). You still have no nitriding until '79, though, thus my preference for first-gen 12As or R5 13Bs if you can find one.
Full Member
Joined: Jun 2004
Posts: 200
Likes: 2
From: BC, Canada
Either motor can be equally reliable!
What is your big picture plan for the car? Parts for 12a getting a little harder to find, not imposible.
What do you have and what do you want to change?
If you already have the carb set up you want, changing to a 13b means a change there same as exhaust.
If the car is going to get a complete rebuild, What do you want.
If you upgrade to more power, what about the brakes and suspension?
What is your big picture plan for the car? Parts for 12a getting a little harder to find, not imposible.
What do you have and what do you want to change?
If you already have the carb set up you want, changing to a 13b means a change there same as exhaust.
If the car is going to get a complete rebuild, What do you want.
If you upgrade to more power, what about the brakes and suspension?
Thread
Thread Starter
Forum
Replies
Last Post
Jeff20B
1st Generation Specific (1979-1985)
73
Sep 16, 2018 07:16 PM
Mrmatt3465
Interior / Exterior / Audio
8
Sep 17, 2015 01:28 PM