OK I'm new to rx7s and I recently got a 1982 first Gen. with the 12A engine in it. The engine bogs and feels underpowered under 3000rpms. I was told by a mechanic that the carb wasn't giving the engine enough gas. I think it is the carburetor but it's also got an exhaust leak. I bought a carb rebuild kit and I'm planning on rebuild the carb and patching the exhaust leak. when all is said and done, If I can get the engine to run smooth and clean I was considering putting a little performance work into it. Intake exhaust and maybe a performance chip. The cars got 120k miles on it, and I was told the Apex seals go bad at about 100k. Is it worth while to put performance parts on it or em I going to be wasting my time?



Anyone out there that can give me some knowledgeable advice?

Well, yes...if taken care of...all Rx7s are reliable. First, I'd fix that carb problem, and the exhaust leak...then, get a compression test done. That should tell you how reliable your motor is. Most naturally aspirated rx7s last way into the 150K+ mileage...its all in how the previous owners cared for the car and how much your willing to do. However, if the motor does prove to be weak, 12As are cheaper to rebuild then most rx7 engines, so you'll be ok...you can do the rebuild yourself for under $500. Look into doing the ATF trick too...its good for high mileage motors..its in the 2nd gen FAQ section...

I would make sure your Catalitic converter isn't clogged. I wouldn't removed it, but 81' was the first year that they got rid of the Thermal reactor and went to straight Converters for cleaner air. If you carb is not working properly, Your converter could very well be clogged.

I have over 180,000 mile on the first one and it is still running and over 140,000 on the second.

Tell you the truth 12As are more reliable than 13Bs.

Don't know about that, I have had one 12A and two 13B's, have over 150K on both 13B's

Rx7's are good cars either it be a 12a or 13b, if your not into it, and don't

mind getting your hands dirty then the 7 is for you,,if not,buy a honda

I just wanted to point out that 12a's don't have a computer (ECU) so there are no performance chips for it. It is carbureted. You should check out the stuff Racing Beat has. Their site is very easy to navigate around and they have a lot of parts and info.



www.racingbeat.com

My 82 has 184,000 on the odometer and it runs real nice. Proper maintenance will help the car last longer. Change the oil every 2-3000 miles, and remember to check it often since the engine burns oil to help lubricate it. Check the coolant and let it warm up before driving it hard. Also try not to turn it off before it is warmed up since pieces of carbon can fall down between the Apex seals and cause the engine to carbon lock. I drove an 87 once that had over 200,000 miles on it, and it had been beat on, so you just never know.

FYI, I rebuilt one of my carbs just for fun the other day. If its your only one, you might want to think twice about that unless you have some mechanical experience.



Skip the overpriced performance crap for now. With 150k you probably need some brake rotors and other high wear parts pretty badly.



To answer your first question, I'd have to say the 12A engine in the 1st gen is more reliable than all other rotaries, with the exception of the normally aspirated 13B that came out after.

hmm, yes. I had 175k miles on mines. I think the misconception(?) that rotaries dont last, specially the 3rd gens, is that people used to increase boost without the remainder of the necessary modifications.

197,300. Lost a lot of power though. I put on a Mikuni sidedraft at around 195,000 and didn't gain any horsepower. I put on RB headers at I think 185,000 and there was a noticeable gain until I overrevved to about 83-8500 and destroyed the stock Nikki. I think now that I have a car to "get around" https://www.nopistons.com/forums/pub...>/rolleyes.gif , I'm going to completely tear apart my 1st Gen and build it like no other. I'm gonna stay 12a though. Hmm.... are 12's possible with a 12a?

Not unless you've got boost, lol. I don't even think a fully built 12A w/ a PP port would run 12s...maybe. You'd have to have it gutted and only weigh like 1600lbs w/ over 300HP all motor...but it won't come cheap or easy...

What the?! You're a psychic. Exactly the same weight I was shooting at and about hte same HP too https://www.nopistons.com/forums/pub...1047683785.gif Maybe I'll go 12a turbo...

dont need to go turbo for 12's in a 12a i've seen cars set up right run in the 11"s with a pp 12a , but they weigh about 1800 lbs and run slicks you can also run 12's with a 12a bp and nitrous with about a 75 shot

I believe you can run in the 13's with just a header, paul yaw carb, and some ignition work.



Another thing I wanted to mention; are you sure its a carb problem? I don't know what else it could be, but when the car isn't running like you want it to, often the first thing people blame is the carb. Have you done the usual tuneup? plugs, rotor and button, wires, filters, fluid change? I don't know if you mentioned doing the ATF trick before or not, but I would definately recommend doing it.



About the ECU, I've been told that the carburated '7s do have an ECU. Thats what all the vacuum solenoids are connected to. If its not right, youll run rich/lean, and it also comes into place with your igntion timing via the advance pots.

When I first got the car about a month ago I did a basic tune up. Plugs, fuel filter, oil filter, and oil change. I haven't done the rotor, distributor cap or the spark plug cables. I plan on doing the atf treatment after I rebuild the carb.



The carb looks like a flying soccer in it's self but I'm pretty confident I can handle it. I've rebuilt a few carbs on trucks but nothing as advanced as the 7's.

I don't know if this is important or not but after I accelerate as the rpms come down the exhaust pops and sputters. I was told that it had to do with the timing.

any ideas of how I can fix that?

that is probably your exhaust leak. or it could be a bad shutter valve in the intake manifold (just plug or remove it).

reliability in an rx huh! I don't know much about that I mean my 86 n/a only has 198,000 miles on it and my dad's 79 only has 320,000+ on his but as for reliability I don't know. https://www.nopistons.com/forums/pub...IR#>/blink.png

Umm Raphalito Racing from PR had the worlds fastest 12A and i think he was doing 7s with it...



ALSO they did make a 12A Turbo..in Japan that should not be to hard to find..mY friend who grew up in PR says he saw 2 of them here..and there was alot over there..

And you dont have to go turbocharged..



You can get a Supercharger cheaper...

look for Atkins rotarys..

12A supercharger is about $2200.

Carburated 7s DONT have a ECU...theres so many little tricks you can do to get more HP out of a carburated 12A...



I was a big beliver of MSD on rotarys..BUT you will be spending alot..

You need 2 MSD boxes..and then 2 coils...



One trick is to get the leading coils...off of a second gen..

stock 12 coils are like 24,000 volts a piece (if I can remeber right)

and second gen is 60,000...



I run a Holley/Racing Beat set up..I dont have any emisson control on..I had the exhast opened up..no cat..etc



Im happy for what I got but im not done..far from being done..

It all depends on how you interpet "ECU".



If you mean a computer, then no, carbed 12A's do not have an ecu.



But if you simply mean "engine control unit", then I believe that mess of emissions control crap, known as the rats nest, is definately an ECU.

Well when most peopel say ECU they mean computer

I just thought somebody should mention that compared to a good six or a V-8, the rotary DOES feel mighty weak at low RPM's. Rotaries need about 3k on the tach before they really start pulling.

I second this, could be the cats. I had one here one time like that , I rebuilt the carb, new plugs, woires etc, and still nothing so in deperation I unbolted the cats and BAM it starter and ran perfect. https://www.nopistons.com/forums/pub...IR#>/smile.png Good luck

OK I rebuilt my carb. the carb seems to be running good. but now I've got a new problem it seems to have a vacuum leek. I'm not sure if maybe I crossed one of the vacuum lines. but the engine idles at 1200 rpms for a few seconds and then it dies. I tried to bring the idle down but nothing helps. It has no bottom end tork, and you have to feather it just to drive it. The engine stalls if you press the breaks or pop up the lights. once you get going the carb seems to work fine.



any ideas ?????