gradedcheese

Well I think I may have a working ignition now but my automatic (which I wasn't planning to keep anyway) started smoking like crazy. It does this after the car runs for more than 15-20 minutes and I can smell fluid burning and see smoke pouring out from the area where the tail of the automatic is and also into the motor bay through the tunnel. The transmision has the correct amount of fluid in it and I have it in "park" when it does this.

Anyhow now that the car runs I think I should just do the manual conversion and be done with it. I'm digging though the old threads but if people could post links and pointers I would REALLY appreciate it.

I have a pedal box from an RX-2 with a manual but I have no other parts. I have the following questions to ask:

- is the clutch master cylinder specific to the RX-2 or can I use one from a different Mazda?

- I am going to get my 4-speed out of a 1st gen RX-7 with the correct shifter location. Should I take the flywheel out of that car as well? Is the clutch I want an RX-7 clutch? Or do I need an RX-2 flywheel of some sort?

- what do I do for a starter? right now I have a "top mount" starter that bolts onto my motor and automatic. Is the manual 12A RX-7 starter a bolt-on to my motor?

- Does a manual RX-2 have a separate fluid can for the clutch or does it use the brake can with an extra line for the clutch?

- should I do the swap in the car or should I go ahead and pull the motor along with the automatic, bolt everything up externally, and then install as one shot?

- I'll want to bypass the neutral safety switch. What other electrical changes do I need to make? Is there an extra igniton relay I need to short and/or remove?

- any other advice? I have done swaps like this on BMW's but never on a Mazda. I'll be seeping the thermonuclear reactor stock exhaust stuff for the time being while doing thi swap.

Thanks, everyone!

Mann

First off.. get the early 5 speed not 4 speed.

You can use a rx7 clutch master. Because on the rx7 the bolts are on the MC, you will need to unscrew the bolts out and drill the hole slightly so they will slip though. Now you can use the bolts already on the RX2 chassis.

I don't believe a 79-80 tranny will bolt up to the early 12a but im not sure. Because of the different starter locations you will have to run a longer battery cable. I will not go any farther because I don't believe the two will bolt together.

gradedcheese

Hmm... so if I want to grab a manual gearbox I actually need one that's out of an early 12A car like a RX-2 or RX-3 rather than an RX-7 because otherwise it won't bolt up?

I'd rather not have to pull an RX-7 12A at the junkyard because those motors are probably in need of a rebuild while my RX-2 motor runs fairly well, it seems.

Detlman

one other thing to keep in mind is that an rx7 trans has the slave on top of the trans and it will hit the floor before you can get the engine/trans in the correct position. Also if you have the starter on the bottom the positive terminal is VERY close to the trans tunnel on the car.

I have been told that an rx4 ( I think ) had a 5 speed that was very strong and would bolt right up to the rx2 with no changes in shifter location or issues with the slave being in the wrong place.

A couple of those I learned on the car I just bought, it had an early rx7 engine and trans and had the issues I mentioned. I am in the process of making the necesary mods to make it work properly. I also scored a rebuilt 12a streetport for $300 ohhh yeah !

Good luck.

gradedcheese

crap Well that really sucks. I can get an RX-7 gearbox for $65 at the junkyard but buying an early 12A one is going to be expensive probably. I'll start looking around to see if anyone has one for sale.

If I can't get a compatible manual gearbox easily I don't think it's worth it for me to keep this RX-2,

Re-Speed.com

iTrader: (3)

I do not think it will swap over either. I do have a gearbox for sale in the parts section. I really did not want to ship it but if you are interested maybe we can work something out. It is a top mount and I have a starter for the manual flywheel as well. I have a few core twin dizzy motors too.


-billy

gradedcheese

billy, I'll PM you

Detlman

for me I like the rx7 trans, it moves the shifter back to a more comfortable place for me. The modifacations arent that hard as long as you have a little time and a little patience, and a welder. With the engine/trans out the mods would be pretty easy and wouldnt take very long.

One other thing that wont work right on the 7 trans is the crossmember for the trans, you will need a custom one for it to fit correctly.

gradedcheese

thanks. the RX-7 trans still seems like too much work for me because I no longer have access to welding equipment and the like. My main goal now is to get the car to be useable, although the automatic is unacceptible (even if it didn't leak or whatever it's doing).

I think I'll give it a couple weeks to see if I can obtain an early 12A manual gearbox and failing that I'll probably get rid of the car

Detlman

I need a few parts if you decide to part it out.

gradedcheese

Sorry, if I decide to get rid of it I will sell the whole car. it's better that way anyhow because it has a good body and motor and it's definitely worth restoring it.

Detlman

No problem, you know how it is to find good parts for these cars. I was just throwing that out.

Wankelguy

What you want is called a "ribcase" tranny. It has a bolt-on bell housing and is narrower than the later "smoothcase" RX7 tranny. The fifth gear is only a fuel-saving measure, they'll go just as fast in fourth.

gradedcheese

thanks, that helps. I emailed a few people selling Mazda junk locally, hopefully they'll have something to offer and I'll be able to identify it.

Mann

I don't agree with Wankelguy on the 4 gear vs. 5 gear issue. I have topped my car out in forth gear many times running my 5sp 80 tranny. Once I shift to 5th I still keep accelerating. I have a friend with a 79 rx7 with more engine mods and once he gets to the top of 4th I pass him in 5th.

Plus, It is easier on the motor if you use it as a daily driver and are on the highway alot. Your motor is running at a lower rpm and it burns less fuel. Now if you plan on road racing then it really doesn't matter, but if this is a daily driver I would suggest the 5sp.

my 2 cents

Jeff20B

iTrader: (13)

gradedcheese, what type of 12A do you have? Twin dizzy with a top mounted starter? Or something else?

gradedcheese

I have the stock original 12A for the RX-2. it has twin distributors, a top-mount starter, and currently an automatic transmission.

I am not planning on any sort of racing, just building a fun daily driver out of it. I will remove the emissions stuff and install headers, different ignition contorol, and hopefully a different carburetor at some point, but that;'s about it.

Jeff20B

iTrader: (13)

I've got a twin dizzy 12A, complete with the correct flywheel and 4 speed manual with top mounted starter. You do know there is a difference between our stuff and '74 and later stuff, don't you? The bellhousing diameter and bolt pattern are different for one thing. Just letting you know.

gradedcheese

oh.....

well, I have a '73 model. Where are you located?