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-   1st Generation Specific (1979-1985) (https://www.rx7club.com/1st-generation-specific-1979-1985-18/)
-   -   79'/80' 12A going into an 82' FB (https://www.rx7club.com/1st-generation-specific-1979-1985-18/79-80-12a-going-into-82-fb-818384/)

OnlyOnThurs 02-07-09 12:19 PM

79'/80' 12A going into an 82' FB
 
im still looking through they archives but what are the major things i need to look for when it comes to installing an SA 12a into an FB. I have a 12A header so i won't need the thermal exhaust they have. CAn i use my carb and other things from the 82 12A and put those on the 79' engine with no issue? Anything else i am over looking? thank you in advance for any help!

boyee 02-07-09 01:12 PM

I'm sure you already have seen this thread: https://www.rx7club.com/forum/showthread.php?t=815367
but I just wanted to link it for future searches since it has some relevant info.

FirebirdSlayer666 02-07-09 03:33 PM

Marcello, I did the same thing you are. Took the 12A out of my SA and put it in my 83 FB. I of course took the radiator and oil cooler out of the SA as well but with the 82 you already have that. Use the 82 Alternator as it's internally regulated and will match the harness and vehicle. You won't have any oil pressure readings since the SA's didn't have an oil pressure sending unit. I would also recommend splurging a little and getting the braided oil cooler lines. You will also need the flywheel, clutch, and pressure plate matching the motor unless you have an aftermarket flywheel that can accept both 215mm clutches and 225mm clutches. It's super easy otherwise as everything else is identical. You can use the FB carb and have no issues but the SA intake will actually be better to use. If you have anymore questions, post them up. I can take any pictures you need also.

OnlyOnThurs 02-07-09 04:17 PM

^^^Damn i love you! thank you for the info....... i will post up more questions as they come to me :)

oh and i already have the stainless steel oil lines :)


do you have an aftermarket oil presure guage on yours that you put on after the fact?

FirebirdSlayer666 02-07-09 04:48 PM

I don't have an aftermarket oil pressure guage yet but I would like to try and add one eventually. I would sugguest doing some searching and seeing how the SA guys put oil pressure guages on as I haven't looked too far into it yet. It would be easier to do any drilling/tapping with the engine out and on a hoist rather than in the car

Rx-7Doctor 02-07-09 11:17 PM

https://www.rx7club.com/showthread.p...ighlight=guage or this-

Oil Pressure & Oil Temperature Adapter

http://mazdatrix.com/boil3.htm

OnlyOnThurs 08-11-09 11:24 AM

I got a hold of another rebuilt unkown year engine from my good friend (THANKS CHAD!) and she runs so my FB is FINALLY back on the road now!! WOOT! But i did notice that there was no oil pressure unit under the the oil filter...it struck me as odd because I was moving things from my old engine to this replacement one and there was no hook up for the oil pressure?!?! Now that i found this thread again i see that this engine i just got has to be an SA engine since it does not have an oil pressure unit. Ill will have to to the aftermarket upgrade like you guys suggested. that seems to be the only way to do it.

DivinDriver 08-11-09 11:32 AM

Use your '82 dizzy, too... 79 had points, 80 used a remote ignitor box & long-cable pickup that your 82 won't have. Should be a straight drop-in replacement; the 81-85 dizzy is a popular upgrade for SA's.

OnlyOnThurs 08-11-09 11:42 AM

yeah im using the FB dizzy :) thanks!


im just trying to get the timing down. so i have been searching like crazy this morning so i can get this 12a tuned correctly. I don't want to be driving it hard with the timing be off.....last thing i need is for this engine to pop because of simple BS.

Jeff20B 08-11-09 01:21 PM

The '79-80 intake manifold is better than the FB style. Just be sure that your exhaust flange will block the thermal reactor air injector holes in the rotor housings. The oil pressure is the only other real issue with SA (R5) plates, but you're already aware of it.

To set the timing by ear (especially if you're unsure about the timing marks and don't trust them), idle the engine and move the dizzy clockwise and counterclockwise until the idle is best. Too far one direction will raise the idle and it will kinda want to miss. Too far the other way will lower the idle and make it not want to run right. So first find the limits and then center the dizzy so it idles best. This will give you full mechanical advance at around 4k and almost no mech advance at idle (make sure the idle is just below 1k or so). Leave vacuum advance disconnected and plug the hose but don't plug the diaphram things on the dizzy. Then when everythng is set, you can connect vacuum advance but I usually don't use it so I can't comment on it.

OnlyOnThurs 08-11-09 02:09 PM

Thanks for the info Jeff! I will do this when i get home.


I have another issue i forgot to address. I HAVE NO TACH!! everything seems hookup correctly. Did I reverse any wiring you think? nothing looks frayed.......

i got the temp gauge hooked up fine and all other gauges are showing up fine (except oil pressure obviously :) ) ....im searching for this tach issue now

wedweb 08-11-09 05:58 PM

Photos? :)

OnlyOnThurs 08-11-09 06:06 PM

i need to wash her then ill take new pics :)

cmanns 08-11-09 06:34 PM

pics! :D

glad to hear shes running again

ChunkyMonkey 08-13-09 10:51 PM


Originally Posted by OnlyOnThurs (Post 9419658)
i need to wash her then ill take new pics :)

Photos or it didn't happen, lol...


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