Was just wondering if I could do a dual IDF setup on a streetport 12a? If so, what size IDF's would be best for that application. Also, where would someone find a manifold for that?

 

the rotary engineering dual DCD were 36's.

 

Sort of. The 13B set up had 28 mm primaries, 36 mm secondaries. The 12A set up had 32 mm primaries and 25 mm secondaries. There is a rare dual carb Lake Cities intake manifold that took 2 Weber 40 mm side drafts. Not sure which model Weber or the actual venturi size. I think I saw one of those manifolds in the for sale section.

 

o ok. i just remember them being 36DCD or something like that.

 

I think you would need a custom made manifold. 2 40mm idf's i think would work out. But I like the idea of using progressive 2 barrel carbs like the ones trochoid and rxtasy are talking about for better gas mileage. A little barrel opens up under part throttle, and the big one under full. 2 weber 23/36s might do the trick for a large streetport, and they only cost $189 new each. But you would still need a custom manifold, which is very pricey unless you have massive fabrication skills.

You would probably happy with a 48mm idf or ida (they need different intake manifolds). Unless you just wanna try something new and different, then by all means go for it.

I think dual 40 idf downdrafts or dcoe sidedrafts would be awesome!

 

Personally, instead of reinventing the wheel, find an RE DCD set up for a 12A, It's the most street able carb for a 1/2 sp/1/2 bp engine around. The carbs were originally set up for RE's own large street port engine. Otherwise, the dual 40 mm Webers sounds interesting, though it may be hard to source the intake mani.

 

I'm asking because
1.it sounded kick *** and I found some for fairly cheap
2. I have a sidedraft 45 on my red 84 and was going to use that, and put a stocker back on the red one. But it would be nice to leave it on and finish tuning so I don't have to do anything else to it.
3. I'm buying another 84 roller with all the suspension mods and a better body than the red one, so I figured I'd leave the motor in it and put the street port into the new (beige) 84, which would leave me with the need for a carb. And THAT motor will be getting the best of what I have. Wheter it's a new carb or the 45.
4. The IDF's appear to be a smoother transitioning carb for the street. and definately easier on the pocket book. But If I'd have to have a manifold made, I'd be best spending the money elsewhere and doing that later possibly. Other than that, I am unfamiliar with the other carbs and wouldn't have any idea how to setup or tune them. I'm just trying to find a carb option that is beast enough for the street port, but not the cost of fort knox, or have to be a carb surgeon to tune/setup.

 

Just get a 48 IDA, then.

 

This is the intake you need for dual 40's. Unfortunately it's sold. Keep an eye on the 1st gen for sale section and eBay or post a wanted to buy in the 1st gen parts section.

https://www.rx7club.com/showthread.p...ht=lake+cities

 

not a very wise decision with your hard earned cash. at the end, you end up buying a IDA

 

Japan12LA is selling IDF manifolds now... I never wanted to use one before because of the flow issues compaired to the awesomeness of the IDA, but with 2 44IDF's and this:
http://www.cbperformance.com/catalog.asp?ProductID=508
It would be a hard setup to beat...
But it would cost tons of money to do. $300 for the mani, $800 in carbs, $200 in linkage, $150 for the update, and $100 worth in jets to get them tuned right might not be worth the risk of it making less power than a good 48 or 51 IDA...

 

I think you meant 25 primaries and 32 secondaries, unless you like your car running funky

 

Also, you can always get a Holley RB intake manifold, and get the ebay Holley-to-dual-DCOE adapter and run 2 40's or 45's.

Or get an adapter for holley to quadrajet. I had everything but the adapter

 

Oops, thanks for the correction. And here I thought I was being knowledgeable with little known details, lol.

 

now i've seen that adapter for the holley. i'd like to see how well it would run. definitely a wicked looking setkup.

 

Here you go and the price is very reasonable.

https://www.rx7club.com/1st-generation-rx-7-1979-1985-parts-101/twm-dual-dcoe-carb-manifold-12a-867731/

 

I found that, and posted to see if it sold, and pm'ed the owner too. But haven't gotten a response to either.

 

You would have clearance issues for a proper side draft filter. Now if you used
shorter trumpets and built a cold air box around them and fed it with a tube
going up side the radiator (ala RESPEED). That would rock. Just make sure theres
a heat shield under the intake and carbs.

 

Heard from him yesterday, it's sold already.

 

I came across an old setup for a flathead V-8, got me to wondering how that would do on a rotary. Dual stromberg or holley 97's or 94's. It would certainly be unique, probably look awsome too. Would a pair of those power a rotary well ya think? Seems like it would. I don't remember them being all that difficult to tune either. (bonus) Hmmmmmm...........

 

Hurley rotary used something like that with huge success. http://www.hurleyrotary.com/page.php...ntpageref=6264 Great fuel mileage and good power. I think it would be awesome!

 

The Hurley setup sounds good, but I couldn't find a decent pic.

 

neither can I. It sounds like they modified them. but it would be cool to try to fabricate something like theirs. I think they want a pretty penny for the setup.

 

I just can't help but want to make things look "old school" Now I know that 6 would be severe overkill, but duals would look sweet on a 7 wouldn't they?!

 

Now wouldn't one of these be pretty under your hood?