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12a manifold on a 13B?

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Old 03-26-11, 05:04 PM
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12a manifold on a 13B?

I have the opportunity to purchase a rebuilt 13B. Does some one make a manifold so I can use my Nikki carb? Or is there something that allow me to use a Holley carb?
Old 03-26-11, 05:27 PM
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its supposed to do that

 
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You left out some key details there, sport...

If it is an early 4-port 13b you can use an rx4 intake manifold. If it is a 6-port you are on your own, although I have seen holley manifold modded to use nikkis.



Isaac
Old 03-26-11, 05:29 PM
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lol, sorry. It's a 6-port. I noticed Racing Beat sells a 6 port kit but it will only work with the Webber carb. I think I will just stick with my 12A for now.
Old 03-26-11, 05:59 PM
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RB also has a holley kit for the 6 port.
Old 03-26-11, 06:03 PM
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You would need exhaust as well as a gslse oil pan to do the swap.
Old 03-26-11, 08:23 PM
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yeah, and i realized I will also need the transmission... too much hassle. It is a streetported 13B with exhaust for $500. Hell of a deal, but I don't see making it work.
Old 03-26-11, 08:56 PM
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You transmission bolts up just fine.
Old 03-27-11, 12:41 AM
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it's worth going 13B, HUGE difference between the 12A
Old 03-27-11, 12:22 PM
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Originally Posted by 84stock
You transmission bolts up just fine.
Are you 100% sure the 12A transmission from a 1983 will bolt up to a 13B from a 1986 N/A? If that is the case then maybe I will go for it.
Old 03-27-11, 12:35 PM
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or the other alternative, keep it fuel injected and forget about the antique carburetor.. improved performance and fuel mileage.

yes it's more initial work but a much better long term investment. like having to treat the car like a princess if you plan on storing it for more than a few months at a time unless you like rebuilding/cleaning carbs.

Last edited by RotaryEvolution; 03-27-11 at 12:37 PM.
Old 03-27-11, 02:53 PM
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Originally Posted by rotordogg
Are you 100% sure the 12A transmission from a 1983 will bolt up to a 13B from a 1986 N/A? If that is the case then maybe I will go for it.
the tranny to rear engine plate bolt pattern stayed the same thru all generations of rotary engines.

but doesn't the 86 and later use a larger dia flywheel is it just the clutch disc that's larger?
Old 03-28-11, 01:43 PM
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Originally Posted by rxtasy3
the tranny to rear engine plate bolt pattern stayed the same thru all generations of rotary engines.

but doesn't the 86 and later use a larger dia flywheel is it just the clutch disc that's larger?
bellhousing bolt pattern is the same from 1974 to now, the pre 73 engines are different.

there are 2 flywheel diameters, and i think 4 clutch disc diameters.

the 68-82 cars use the NA size flywheel with the 215mm clutch disc.

from 83-92 the NA cars still use the NA flywheel but the clutch disc goes to 225mm

since its the same ring gear, you just order the right disc and PP for the flywheel, and its compatible with the trans.

the TURBO cars use a bigger flywheel, which takes the turbo trans. 86-88 use a 240mm clutch, and then the 89-now uses a 235mm clutch.
Old 03-31-11, 09:06 AM
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Someone posted a site in Aussieland that had all kids of adapter plates. I don't know the link or where to even begin looking for it. Maybe someone else can help if you're still looking to pick up this motor.

I'm currently running a 12A carb on a 13B w/the use of a adapter plate. I believe the secondary jets were upped one size and it runs great.
Old 03-31-11, 08:52 PM
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tweakit carries them, or did. But, it was for a 12a to old school 13b.
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