hornbm

Hi this is my first post, and I have just purchased a 85 GS (auto trans) with a blown engine. I have someone willing to sell me a 89 non turbo 13b. He is getting this from his parts car so I would have access to any parts that I would need to take out of the 89.

My question is how do I go about doing this. I've been researching this for quite some time now and I've found nothing but conflicting information. If anybody has written up a proceedure list on how to do this that would be greatly appreciated as well. Thanks in advance for any info you could provide!

Directfreak

iTrader: (2)

Carbed or Fuel Injected?

INFO

hornbm

The 85 12a engine is carbed, and I'd like to carb the 89 13b engine as well.

hornbm

I have come accross the mentioned web page before, and thats some of the conflicting info I got. That page says you have to use the front cover from the 12a and others say you do not.

Idealy I would like to run the 13b exactly as it's run in the 89 rx-7 except for the engien being carbed.

So id I were to use the 12a clip I would need:
89 engine block
the 89 ECU
the 89 wiring harness
13B mounting plate
GSL-SE oil pan
and the rest of the stuff would come from the 12a parts?

MIKE-P-28

iTrader: (1)

Good luck on getting that middle engine mounted motor in the chassis like it is in the 2nd gen. Its very possible, but way easier if yuo just use a 12A front cover... Also the engine is 3/4" longer you need to mod the engine mount or buy the RB one

Otherwise it pushes the trans and shifter back and you will have to chop metal, and shorten the driveshaft etc

MIKE-P-28

iTrader: (1)

Oh and if you are running it carbed Why the hell you need the wiring and the ECU?

RacerX7fb

The front engine cover from the 12A or GSL-SE, which are the same has to be used in order to use the distributor, and more importantly to use the front engine mount. The 89 engine mounts are on the sides of the housing. GSL-SE front mount must be used as well or slot the 12A one to make it fit.
It's pretty much a straightforward swap.. bring it on down to this end of the border I'd be glad to help ya

RacerX7fb

O yeah, if you are gunna carb it, you'll also need the oil metering pump off the 1st gen, which one ( 12A, 13B SE ) depends on your choice of intake manifold/carb combo. The 89 one won't work.. is that why you needed the ECU?
Take notes from Mike-P!

MIKE-P-28

iTrader: (1)

LOL thanx

But I forgot what you said, you use a 12A or SE dizzy you will need the apporipriate front covers

rx7passion

hell your in seattle man theres plenty of knowledgeable people aroudn (not including myself) . getting the motor in the car is the easiest part.

hornbm

Ok so the only thing I need from the 89 is the engine? The intake/exaust manifolds will all work from the 12a? I'm going to buy that 13b mountig adapter from mazdatrix that allows you to mount a 84-85 13b. and use this instead of slotting the mounts?

Redwood

Whoa, whoa, whoa, here's the low-down on what you'll need.

-85 body
-12a or 13b(GSL-SE) front cover
-13b oil pan (GSL-SE)
-RB 13b adapter mounting plate
-No wiring, since you're going carb
-A new exhaust system (there's no way you'll be able to mate the 13b exhaust manifold to the 12a exhaust, since they're different diameters). Just get a header and then take it to an exhaust shop and get straight pipe to a straight through muffler. I was quoted $125 for this by one shop.
-A carb with a 13b adapter (this is not my field )
-89 13b with all the miscellaneous vacuum crap and whatnot

In short, you'll use nothing from a 1st gen (save the front cover and oil pan). Everything else will need to be taken from the 89 or built/purchased. Good luck.

Oh, and if you'd like to see the swap done, I also live in Seattle and would be happy to show you mine.

hornbm

Finally! Someone from the seattle area that has done this! This is going to make things alot easier... Thanks!

MIKE-P-28

iTrader: (1)

Yeah must be nice to live somewhere someone knows something about what you are doing , rather than going 'hell if I know' or wow wheres the valve covers

fatboy7

valve cover... LOL .. I know exactly how you feel

Directfreak

iTrader: (2)

What are you insinuating?

Tom93R1

iTrader: (2)

I believe there is an adaptor plate you can buy that will allow you to use your old intake manifold/carb with the newer motor. Sometimes you can find that kind of thing on thepartstrader.com.

Redwood

Oh, I just realized something. Are you planning on sticking with the 12a auto? I'd suggest getting a 5 speed in there. You'll need everything necessary to make the standard switch (meaning nothing special) if you plan on this. The 89 tranny is pointless to retro-fit as the internals are nearly identical (both pretty weak). Any 12a tranny will bolt right up though, so that's nice.

Also, cpt_gloval has done (or is doing) the same swap with a series 4 engine and a carb. He'd also be willing to help/show off his car I bet. Between the three of us, I'm sure we could get that car done in a weekend.

moremazda

iTrader: (4)

I wanna help, too!!!!!

Ryan

hornbm

Well my plan is to swap out for a 5 speed eventually. I just don't have the money now. After all... i'm 17 and this is my first car completely earned from timeless hours at a minimum waige job.... I cant wait till i'm 18!

But basically heres the plan so far. The 85 GS i'm getting has a blown engine. I dont want to put money into a 12a so thats why i'm moving to the 13b.

I'm going to pick up the block from pineapple racing in portland as they seem to be the best in the area and I know someone who said he could get me a really great deal.
Then I'm buying all the rest of the boltons... etc from teh former president of RPNW (rotary power noth west)'s 89 parts car. Every thing looks good this car just my dad wants me to write up a detailed proceedure for the swap so i dont forget to get a part and/ or f*** up in the process.

So far the swap is going to be done in my autoshop class and should work out unless for some reason the swap were to take more than two weeks to complete. I'm guessing a week at the most.

Since I would like to still use the carb from the 12a in the mean time, that means I would have to use the 12a intake manifold? So basically i need to confirm somthing.

Exactly what do I need to remove from the 89 parts car?

85TIIDEVIL

iTrader: (2)

All you need from the 89 parts car is the motor/block..

Then, from a GSL-SE you need a oilpan, frontcover, and the motorbrace/mount. If you can't locate a GSL-SE parts car you can get all these parts from Racing Beat or Mazdatrix.

Also from RacingBeat or Mazdatrix you'll need a fuel injectior plug kit... or... you could get the fuel rail off the 89 motor and the 2 injectors and use them as dummys. You might have to hack/cut/ruin the fuelrail to fit the carb atop of it.

You'll definatly need a adapter to use the 12A carb on the 13B (if they do sell one the jetting/etc on the carb might not be right, something you'd want to look into from someone w/experience like Pinapple Racing)

You'll use the stock 12A coils, wires, distributor, oilmetering unit, throttle cable, oh.. a 85 gs model comes w/a coolant-oil oilcooler (garbage) so you'll need the air-oil oilcooler off of the 89' also.

Ok.. you're 85GS is an auto... this could be another job in it'self... If the 89' is stickshift you best bet is making the 85 stick too. If the 89 is automatic, you need to find out if the 12A automatic tranny can be used w/the 89' autoflywheel and counterweight.

Eitherway keep the autoflywheel and counterweight, or stickflywheel, pressureplate and clutch from the 89'. Grab the COMPLETE tranny from the 89' too if you can in case you need to convert to stick now or later.

You need headers... actually... take the exhaust manifold off the 89'... use that for the time being and have a Muffler shop attach your 85 exhaust system to the 89 exhaust manifold, unless u could do it in shop class...? ohhh... Redwood's right about the diameters not matching if you're exhaust is still stock... i guess you'll either have to repipe the whole exhaust system or score some headers.

Definatly get rid of ALL the emmissions crap, when you swap the 12A carb onto the 13B motor. You'll need some block off plates from RacingBeat for the EGR & air control.

I think that's it... oh... you're stock 85 fuelpump MIGHT not cut it... but it'll definatly get the car started. I know I repeated alot from what others have said.. I'm just thinking aloud and this way you'll know more then one person/s have the same advice.

MIKE-P-28

iTrader: (1)

That you suck, cause you live within pissing distance to a rotary shop and have access to good tuners, within driving range

RacerX7fb

oops.. I said earlier that you can use the GSL-SE front mount, I made a mistake about that, the crossmember on the 12A cars are different and wont accept it. Slotting it will work but go ahead and just buy the RB one.
and yeah, don't you just love it when you see ads with RX-7s for sale that read on like : " clean, runs well, 4 cylinder..." wtf?? hahhaha

Bjurr

Oh, maybe you guys could give me some advice. I'm planning the same stuff as our friend here, hornbm. I just bought an '85 GS with a blown engine (12A, 5 speed). I went to a local shop (carrera motors) wich deals alot in Porsches and Rx-7. Talkin a bit to the guy about what I wanted to do with the car, he told me he could rebuilt the engine, but "cost wise", I'd be better off getting a new engine from Mazda instead.

The idea was going for a rebuilt 12A street ported with either a weber or dellorto and a decent exhaust system. The guy then advised me, since I'm probably going for a whole new engine, to get a 13B instead since it's going to be easy to fit because I'm already planning on some aftermarket carb and headers.

The thing is which year of the 13B should I use? I know some years were rated higher than others but is it mostly because of fuel inject changes, or the engine block/parts?? Are some years/models more expensive than others? (btw, I don't wanna put a 1993 plusengine in there....I know, they are not cheap).

Directfreak

iTrader: (2)

Ok. That's what I thought you meant.