Rotary 13B swap...

[jchristians]

Anyone here done one?? Stupid swap? Crazy amount of work? I have access to a nice 13B engine/tranny from an '86 RX7. thx!

[ComicArtist]

'86 is a good year to start with, for a few reasons.

 

Since it's an S4 motor, there's minimal wiring involved. Find a wiring diagram for an S4 13B and whatever you're swapping it into and you'll be golden. I think there's only like 5 or 6 wires that are actually critical for it to RUN.

 

Also, it has a mechanical oil metering pump. The S5's, although having higher compression and making more NA power, is run off the ECU and makes it harder to swap. Also I hear a lot about them failing, so S4 is the way to go.

 

I wish I knew more about rotary swaps... I was planning on doing a 13B in the Miata at some point so I read a lot and did a lot of research, but there's still mountains of knowledge I'm clueless about.

[RedBanner]

F the omp, run 2 stroke oil, like every one else.

[daf]

Go big or go home

 

 

lol

[ggzilla]

Go big or go home.

 

 

Forget the little 3-rotos

 

[jon521]

not sure on amount of work, but the guy i bought my truck from said he used to live in cali, and that he owned 2 521s with 13bs in them. so its doable

[Farmer Joe]

well other than the wiring, it mainly making motor mounts, and probably a driveline..

 

the wiring, at least in my eyes, would be the hardest part...

 

i had a 12a that i was going to put in my old isuzu pup.. never got finished tho.. the engine is small enough that theres not firewall or frame changes that have to be made. im not sure on the steering and the oil pan clearance with the datsun, but with the pup, the oil pan fit right behind the engine crossmember..

 

put the engine in the bay, and just get started.

[ggzilla]

yes, it would be just as difficult as a KA swap. It's doable, but ...

[I'm BLUE]

(1) Research , Research , Research !!! :D ( look up dimensions of motor , placement of exhaust , placement of motor mounts , wiring diagram , etc ,,, then measure your motor , your placement of exhaust , placement of steering ,,, etc ,,, )

 

(2) Get as complete parts/swapengine/wiring car as you can ,,, always cheaper !!!

(3) Sure ,,, anything is doable with time , skill , $$$ , resources , and experience :)

 

(4) Do you know how to weld ?

 

(5) Do you know how to wire an engine or possible ECU ? ( not too bad ,,, just study study study ! )

 

(6) Driveline angles are important as well as crankshaft centerline ! ( easiet concept to grasp , can be hard to execute ! )

 

(7) Prepare to "Possibly" have to clearance things with a reciprocating saw , hammer , and/or torch ,,, then be able to patch up and reinforce ,,, metal structural places as well as cosmetic ones

 

(8) With more power comes ,,, more demand for handling(suspension) , and braking ;) ,,,,, add this into your budget :D

 

 

Note: Engine Centerline ,,,Weight Distribution ,,, Clearance ---> (especially around steering/exhaust) are very important ,,, and can be set-backs ,,, Learn how to weld if you don't know or have someone handy with you that can ! ,,,

[DAT510]

A Rotary's motor mounts are on the front of the engine, so new motor mounts are a must.

[pope_face]

What DTP said, and...

 

I was toying with the idea of putting a 12A in one of my trucks, although that's been suspended indefinitely... I suspect (if you wanted a rotary) a 13B would be a good way to go: It's fuel-injected, so I suspect it'll probably get better mileage and/or power than a carbed 12A; it's a newer engine (so hopefully fewer issues); there are "go-fast" parts available; and, it should be easier to go forced induction, if that's your plan. Personally, I preferred the 12A because I like carbed engines (I can actually work on them, unlike newer engines), and there's less wiring to worry about.

 

 

[fisch]

Drastic520 did one in a 520.

Madcow goes brap

[Str8_69]

What DTP said, and...

 

I was toying with the idea of putting a 12A in one of my trucks, although that's been suspended indefinitely... I suspect (if you wanted a rotary) a 13B would be a good way to go: It's fuel-injected, so I suspect it'll probably get better mileage and/or power than a carbed 12A; it's a newer engine (so hopefully fewer issues); there are "go-fast" parts available; and, it should be easier to go forced induction, if that's your plan. Personally, I preferred the 12A because I like carbed engines (I can actually work on them, unlike newer engines), and there's less wiring to worry about.

 

 

Not all 13B's were fuel injected.

[albyneau]

(3) Sure ,,, anything is doable with time , skill , $$$ , resources , and experience :)

 

 

 

And not necessarily in that order! ;)

There was a 521 on ebay about 2 months ago I think~ had a rotary motor/trans and Samurai transfer case/axles. Sounds odd given the rotary's lack of torque, but Sammy's final drive ratio's 5.25/1~ so it's got some potential there. It never sold (at that time) so you might think about searching ebay/CL for it~ might still be out there. Buy it and save yourself the work~ or contact the owner and pick his brain....

 

Peace~

Scott

[ggzilla]

Why would you want more cubic inches? 12A revs harder.

[ggzilla]

Besides, 13B is old. First one came out in 1972.

 

The newest one is the 20B, first came out in a production car in 1990 Mazda Cosmos.

[RedBanner]

12a and 13b = everywhere

20b = not

[Str8_69]

Why would you want more cubic inches? 12A revs harder.

 

 

Besides, 13B is old. First one came out in 1972.

 

The newest one is the 20B, first came out in a production car in 1990 Mazda Cosmos.

 

 

13B is the same engine just a little longer, as it has thicker rotors. More H/P and torque than a 12A, and more of them were made than any other Mazda rotary to date.

['70 521 L16]

I remember reading somewhere that re-routing brake lines would be necessary to avoid the super hot exhaust. Even at that though, it sounds like a pretty sweet swap.

[RedBanner]

I remember reading somewhere that re-routing brake lines would be necessary to avoid the super hot exhaust. Even at that though, it sounds like a pretty sweet swap.

possibly fuel lines , but youl need bigger ones any ways, theres several header types, the cheap rb ones fit the best .

[ggzilla]

Rotaries don't have super hot exhaust, unless you modify them.

 

Go with a stock 13B and you'll be suprised how much power it has. Even in the RX7 it was suprisingly fast. Now put that in a lighter car like a 510 ...

[mrbigtanker]

I had a 13b six port street port with a down draft 48 Ida and it was putting down about 230-250 hp