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-   -   Rotary Starlet (https://www.rx7club.com/old-school-other-rotary-63/rotary-starlet-627716/)

55superbeetle 02-26-07 09:54 PM

Rotary Starlet
 
I have a 83 starlet that i want to swap a rotary into. I picked up a 12a with a weber sidedraft on it. I would really like to turbo it. I am a vw bug guy so i have lots of experience blowing thru carbs. Is it even worth it on the 12a? how much boost will they take? What do u guys do about the timing do u just lock it out? The car will mostly be used for a driver and autocross. Would a 60 trim t3 with a .48 hot side be too small?And would th first gen tranny be ok or should i get a secnd gen? I also noticed that there seems to be some kind of oiler that feeds the intake mani, how does this react to boost? Sorry for all of the Q's but i want do get this swap rollin the stock 50 horse just aint cuttin it. I'm hoping for 150 out of the rotary

Thanks
Jeff

81gsl12a 02-26-07 10:12 PM

the 12a takes to boost very well... your best bet is the 1st gen section and or searching for 12at or 12a turbo... the max is like 21 psi for a stock 12a altho it wont last much longer then a week :) you can do a niec 10psi and be well over your 150hp... ez set up would be

12a stock ports, gslse oil pump, high psi oil reg, FMOC, 2nd gen turbo & manifold, then an adaptor 13b to 12a, blow thru carb, carb hat, FMIC,IC piping,turbo II tranny good clutch, boost controler,BOV, mod the 2nd gen waste gate, boost gauge... i think that about sums it up

81gsl12a 02-26-07 10:23 PM

or you could buy this https://www.rx7club.com/showthread.php?t=627646 it just went for sale and im sure it will goo pretty quick.........but if you want a 12at its everything you need for under 1200.....well every tihng but a wide band o2

55superbeetle 02-26-07 10:55 PM

Thanks for the replies. I searched and read alot. I have plenty of turbo stuff to make it happen and i can make anything i need so im not worried about that. The question i still havent been able to find the answer to is the ignotion timing. In the vw world i just weld the distributor and lock the timing at 24 but i dont think thats going to apply here. I also noticed that with the weber the vacum advance pods were not in use. Whats the proper way to do this?

81gsl12a 02-26-07 11:15 PM

you do pretty much the same thing welding the distributor to full advance and running the vacum advance.... im about 95% sure this is the right way. as for timming im not sure what to tell you to run it at guess that depends on your fule and the boost you are going to be running

i will ask my friend that ran a 12at set up for a long time and i will get back to you

cheers PaTricK

81gsl12a 02-28-07 11:10 AM

if you lock the distributor then you do NOT use the vac advance. for an n/a setup i would run around 25 - 30 degrees. on a turbo setup you lock it around 15 degrees for 10psi or less and then 11 - 20psi keep it around 10 - 12 degrees.

from my friend zac

55superbeetle 02-28-07 03:14 PM

Thanks!!!
Im picking up a trans today. The motor i have came out of an auto 85. what flywheel do i need? does it have to be the same year?

Thanks again

Jeff

81gsl12a 02-28-07 06:37 PM

what tranny are you gettin... hope its a TII (turbo II) tranny.

55superbeetle 03-01-07 04:41 PM

No its a second gen n/a trans. I got the trans driveshaft and clutch for a hundred bucks so i couldn't pass it up. Im close now to having all the stuff i need.

81gsl12a 03-01-07 06:16 PM

you can get a light weight flywheel and use the auto tranny weight... or just get the 13b na stuff

55superbeetle 03-01-07 06:28 PM

Are they all interchangeable? A friend told me that i needed to get one from the same year as the engine so it wouldn't affect the balance. Is that true?

fluffysheap 03-01-07 07:21 PM

It doesn't have to be exactly the same year but it needs to be from the right group. I think for 12A it is 74-82 and 83-85. But I could be wrong. Best is to get an aftermarket flywheel to match the transmission, with a counterweight to match the engine, since the flywheel on the 12A (215mm) won't match the 13B clutch (225mm). I think I have this all right. It might be that the 12A in 83+ had the big flywheel and not just a different counterwight. If I'm wrong I'm sure someone will correct me...

The 81+ NA transmissions are stronger than the old ones and should hold up except at the drag strip - 1980 and older are actually pretty weak and will probably break. Stronger yet are the RX-4, REPU, FD and Turbo II transmissions. Those are pretty tough.


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