Newbie
04-30-2008, 04:22 PM
#1
Member
Thread Starter
Join Date: Apr 2008
Posts: 96
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.
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.
05-01-2008, 02:31 PM
#4
Senior Member
Join Date: Feb 2005
Location: Kissimmee FL.
Posts: 1,579
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...
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...
05-02-2008, 04:49 PM
#7
Member
Thread Starter
Join Date: Apr 2008
Posts: 96
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?
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?
05-02-2008, 07:57 PM
#10
Senior Member
Join Date: Feb 2005
Location: Kissimmee FL.
Posts: 1,579
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?
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?