Hi Folks - have had my 1987 na RX-7 for 2 problem free years now but a sudden drop in power and missing led to a compression test showing #1 rotor low - #2 ok. There is also white smoke from the exhaust. Sounds like a blown apex seal to me but I'm still a newbie to rotarys - anything else it could be?
I found a good deal on an 1984 bare engine -86000 miles - no intake, no exhaust, or other peripheral smog stuff on it. My question is this: can all the external parts from my 87 engine be swapped over to the 84 engine? I realize that the 84 had less horsepower but my financial situation is pretty dismal right now and I cannot afford a complete rebuild on the bad engine. I just want a decent running engine again. Is this feasible?
Any tips or suggestions are appreciated.
Thanx!
Tom

 

yes, tho getting an S4 block would be a better choice

 

No, the S4 engines have side motor mount, all first gens have front mounts. It should be fairly easy to pick up a decent used 2nd gen engine. The S3 13Bs are getting much harder to come by. You just got lucky with this one.

 

I never even considered a motor mount problem. So your saying the mounts from my 87 cannot be swapped to the 84 engine? BTW I ended up buying the 84 engine for 100 bucks before I got your response. The price was just too good to pass up. But if I cant swap it then I guess its up for sale.

Tom

 

Compare the mounts on the 87 to the SE engine. I believe there is a provision on the LH side of the center iron to accept the 2G mount. You'll need to remove the oil pan on the SE engine to see if it has the needed bolt holes in the center iron on the RH side, but I don't believe it does.

100 bucks is a steal if it's a good engine.

 

Intake's are quite different I know that, not sure about exhaust or the injectors but as well the motors themselves are quite different so I don't know if the ECU would work.

 

It's definitely possible. I have seen an FC with an SE motor before. It was a preproduction owned by Jim Downing. Distributor and everything.

(in terms of how it was mounted and stuff, it may have been a one off job from Mazda, I don't know if any fabricating is required, I am just saying I saw an SE FC)

 

Thanks for all the great feedback guys. The engine I bought does have 4 threaded holes in a square pattern on each side of the engine which now makes me wonder if I really have an 84 engine (if they were front mounted) or the original owner swapped in a later engine. The rotor housings have the letter "K" stamped on them and the engine number is stamped "F 14608". I cannot find any cross reference lists anywhere that gives me what year a certain block number corresponds to. Can anyone point me in the right direction?
Thanks,
Tom

 

There really aren't any identifying numbers or letters. It's mostly just differences in appearance, egr, etc.. On the RH side, the 2nd gen engine mount bolts through the oil pan. You'll need to remove both oil pans and compare bolt holes.

 

SE engines do have the holes to. The GSL-SE was basically a prototype for the FCs, so they had both engine mount locations, but the oil pans are different. Here is that preproduction FC with a first gen 13BI told you about:



The woman in the pic is Holly, she used to have an FD, and she works for Jim Downing. She'son these boards and knows a lot about the car, but I doubt she knows anything about the mounting and stuff.

 

This should be the easiest way for you to figure it out. look at the intake ports and figure out which yours fits.
GSL-SE Intake:

S4/5 n/a Intake:

 

It's not the lower intake one needs to worry about, it's if the FC UIM mates to the SE LIM. That pic that's posted has an S4 UIM. If the swap to the FC UIM can't be made then the entire SE wiring, ecu, intake system, injectors, etc., etc., will need to be swapped over too.