OK So I am pretty much set on buying a 1980 RX-7. I've always liked the FB RX-7's and I found a CLEAN one cheap! So that is great.



But it doesn't run right, and I'd probably eventually want to do a motor swap anyway, so I might as well do it now (or soon). But I am new to the whirling box of wonder.



I'd love to swap in a turbo motor out of an FC, if I could find one. So that's where the questions come in. Am I correct to assume the FC motor will bolt up to my trans? What is the difference (internally) between the turbo and non-turbo? Fabrication is not much of an issue for me, and I know how to turn a wrench, and the junkyard is full of non-turbo engines- cheap. What kind of engine management is recomended? I'd like to have something with tunability so the stock ECU won't cut it, but I must admit the Megasquirt scares me a little. Anyone have a guide for running a MS-powered rotary? Anything else I should know about the swap?



Any help you can give me is greatly appreciated.

Welcome to nopistons!



I'm moving this to the 1st gen section (since you said 1980), you should get more answers there.

Thanks for the move. Now I look forward to the answers!

first things first, buy the Rebuild DVD from atkins or the mor exspensive DIY-Rotary DVD set. that taught me everything i needed to know about rotary when i first started.



if your set on using a 13b from a second gen, you can get them pretty cheap from eBay. or maybe find them loaclly.



just put the front cover from your 12a motor so the stock motor mounts can be used. and get the oil pan and oil pick up from a GSL-SE for clearence. and yes, you can use your 1st gen trans. if you use a Turbo II motor, swap the flywheel for the N/A one. you could use your 12a clutch or any N/A clutch and pressure plate set-up. the Turbo II has a larger shaft and more splines.



(NA's have higher compression rotors than the turbo motor. and exhaust ports are smaller and have this bridge thing in it. the turbo motor has 4 intake ports. and the NA's have 6 ports) look up some pics and you'll see what i mean.



now that the motor is in, you have to decide if you wan to run a carb or fuel injection. a distributor for ignition or keep the CAS with the stock FC coils or aftermarket.



ECU choices are endless, Haltech, Microtech, Megasquirt, Apex-i....what ever.



carb is cheap and easy, but limited. a 89-91 NA 13b with a racing beat intake manifold and headers, holley 600 tuned just right will be plenty of fun for that 80.



TII with full turbo back exhaust, front mount intercooler and and nicley tuned ECU will smoke any pair of tired you put on that car. try to get a LSD from any other year 1st gen. if it has disc brakes it has LSD. all years are a direct bolt in.



hope this helps...

Thanks! That was really helpful. I'll be sure to pick up a rotary DVD. I just pray I win that auction now (for the RX7... should've just "bought it now"... but I'm retarted lol)

where you located?



theres a bunch of 1st gens for sale around my area.

Milwaukee, WI. I have a tow vehicle available but would like to get it from the great lakes area.



Another quick question- which engine flows better (without boost), the 13B turbo motor or the 13B N/A motor? You said the N/A has 6 intake ports, but smaller exhaust ports. How do the N/A motors do with boost, or is that just a bad idea? I can't find a turbo motor (in a junkyard or cheap elsewhere) to save my life.



Also about how much hp/tq would a freshly rebuilt 12a with the carb and headers pull?

Err change that to a freshly rebuilt 13b n/a

And how much nitrous can an n/a 13b handle? I loves the nitrous. Maybe that would be a better route than turbo...

the 4 ports flow way better. all turbo blocks are 4 port. and a lot of people will tell you not to use high compression rotors with boost. they can be just as safe with a nice tune.



but, if your going turbo. use the TII block. you can get them on eBay with the tranny and everything thing else for a decent price.



i think your best route (cheapest and easiest) would be to rebuild and port the 12a. or rebilud and port a S5 (Series 5, 89-91 6 port non-turbo. highest compression rotors 9.7...86-88 non-turbo are 9.4)



horsepower would depend on many things. kind of port. how big/wild you go with port. type of exhaust. (the faster it is, the louder with rotarys.) fuel injection or carb tuning...



what type of power you looking for? street, strip, or what?

oh...and i have heard of people shooting up to a 350 shot wet in race applications. but the bigger the shot. the more damage it does.

I'd like to get somewhere in the 225-250whp range, and 325 with the juice. Loud doesn't bother me, and screw the neighbors https://www.nopistons.com/forums/pub...IR#>/smile.gif This isn't going to be my daily driver, and a fairly wild street build is fine by me. I do want it to be "liveable" on the street though, and able to run on 93 octane. Do you think this is possible with the 12a?



I was considering that it may be best to just use the 12a for now, at least for this year and maybe next year too, until I could afford to build a nice motor and drop it in.

with the power your looking for, turbo is the way. to have that power NA the idle would be erratic and the car wouldnt be great on the street...



a nice easy way to get that power would be to turbo the 12a. but fabrication would have to be done. i never heard of anyone making a turbo manifold for the 12a. so you would have to make one, or have one made. then a downpipe would have to be made. and intercooler set up. now your decision would be to stay carbed or convert to fuel injection.



if you were to stay carb, you would need a holley 600 and racing beat intake manifold. both you can get pretty cheap. and they make carb hats for the holley so you can turbo it, but they are fairly easy to make also. the problem is tuning it. you would have to find somone whos knows rotary well, plus holley tuning.



a little more exspensive way is to convert it to fuel intection. you would need a custom intake manifold with basically any throttle body (one from a mustang would work great) 2 fuel rails made and fit to your custom manifold, and 4 injectors. most likely two 550cc for your primary, and everyones favorite...two 1600cc for your secondary you could keep the distributor set up but i would convert it to the 83-85 distibutor. much better...the fuel pump would have to be changed to a fuel injection style pump. get it form jegs, great deals on them. or eBay. and a fuel pressure regulator for fuel injection.



carbs usually need around 6psi of fuel. so the fuel pump and regulator are only made to handle and adjust to that, depending on the car. fuel injection will need around 30-40, depending on your set-up. so getting the right regulator and fuel pump is very important.



now alls you would need is a fuel only ECU. or a full stand alone. the cheapest way would be a megasquirt. i seen them on ebay all the time pre-assembled for 200 or a little more. wire it all up...



and get it tuned...



whats your budget looking like? that will be your main decision factor...

Well for right now my budget is looking like: "Buy car, get it running." I won't be modding it until at least this summer or fall. For this year I'll probably lightly mod the 12a, like a holley manifold and header, I have a nitrous system laying around so maybe a 50 shot for a little extra "oomph".



But I won't bother boosting the car until I can go all out and build a pretty wild 13b. If my budget won't allow that this year, I might pull the 12a and get it ported and do a rebuild so it'll be quicker next spring when the world thaws lol.



I'm definately not looking at this car as a "get it done now" car. I figure I'll do some light mods this year to make it a little quicker, then maybe do the bodywork and paint this winter, and hopefully by spring have a refreshed motor to drop into it, either the 12a rebuilt, holley'd, headered, nitroused and ported, or a boosted 13b (but most likely the former).



Thanks a lot for your input and ideas. I must say you guys ave already been 10x as helpful as 240sx guys (I was looking at a 240sx before I found this car).

glad i can help, 240's are good. but i have found them people to be kinda like the honda guys... a bunch of cocky ass holes with no respect for cars. most rotary people you'll find have a comradary. if im driving one of my rx7s around and see another, they'll usually flip there headlights or wave.



the only thing i can compare it to is riding a bike. when you see someone else on two wheels, stick your hand out to say whats up. when i ride in my brothers civic...all i see is people grilling or challenging. same thing in my boys cars.



welcome to the comunity or:



No Pistons, No Problems!

If you want to get some info on using the Megasquirt on a 13B, go to Ausrotary and do a search as a couple of guys on there are using it.



Mal

actually these days the stock ecu IS tunable, www.pocketlogger.com which is damn cool.

Ah cool!

SICK