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-   -   weber carbs and 12a's (https://www.rx7club.com/1st-generation-specific-1979-1985-18/weber-carbs-12as-44849/)

Audio Science 01-12-02 08:02 PM

weber carbs and 12a's
 
I don't know anything about carbs so I'm going to ask you guys. It looks like everybody is running 48 ida webers. what about the 40 and 44. And whats the difference between IDA and IDF. Can I run a 44 IDF on a streetported 12a and still expect a substancial gain?
Thanks guys

FuLLsMoKe 01-12-02 10:19 PM

i think (i might be wrong) the 48s are not being produced anymore... and i also think that the weber 44s carb are only... 2 or 3 barrels

i would prefer a holly carb, they are 4 barrel and allow more gas and air in compared to most webers...

of course i may be wrong...

Rotortuner 01-12-02 11:15 PM

The IDA's havent been made for more than 5 years. You definetaly want the IDA over the IDF if you want a weber. The IDF's have a diafragm rather than a piston accelorator pump. You realy want the piston pump. Also I think there are more jets and immulsion tubes avaliable for the IDA. This makes it very adjustable to the application. they have changable venturies which it cool, not the average 4 barrel can do that. Any ways I own 1 and it is going on my p port. I would say though that unless your going with a huge street port or bridge or bigger than the IDA is not worth it. My recomendation would be to get a stock niki built by YAW power. He can bring them up to flow almost 450 cfm. I have heard that they are ausome and more affordable then a holley. All you do is send him your carb and he comletely re works it. check it out. Sorry I don't have his web page handy.

CJG

Rotortuner 01-12-02 11:22 PM

here:

http://personal.riverusers.com/~yawpower/

Audio Science 01-13-02 12:28 AM

Thanks guys. Whats the most hp you've seen from a yaw carbed 12a. Any extra amount of mods included.

REVHED 01-13-02 01:49 AM


Originally posted by FuLLsMoKe
i think (i might be wrong) the 48s are not being produced anymore... and i also think that the weber 44s carb are only... 2 or 3 barrels

i would prefer a holly carb, they are 4 barrel and allow more gas and air in compared to most webers...

of course i may be wrong...

You're wrong. Let's say you have a 2 barrel carb with x total area compared to a 4 barrel with the same area the 2 barrel will flow alot more. It's something to do with the "wetted area". There was a thread discussing this at Mazspeed.com.

Anyway, the Weber is the preffered carb of virtually all serious rotary racers which speaks for itself. About the only reason I'd run a Holley is if I was running a half bridge-port and needed the staged secondaries but you just can't beat the performance and adjustability of the Weber.

V8kilr 01-13-02 04:41 AM

what about the del'orto and mikimu 's?

V8kilr 01-13-02 05:28 AM

how much does paul charge for those super street carbs anyway.couldnt find it on his site.did you notice all the hosepower was between 6-8k,im not taking my rotary up to 8k.forget that.when that buzzer sounds its time to shift.

rotorhead 01-13-02 11:39 AM


Originally posted by V8kilr
what about the del'orto and mikimu 's?
dellortos and weber sidedrafts are very similar. the dellorto offers much more in the way of fine tuning, but the parts can be tough to find. both are excellent carbs for the rotary. i'm not too familiar with the mikuni, but it looks very similar to the webers and dellortos, only smaller(44 vs 48).

Audio Science 01-13-02 12:00 PM

So would the 44idf be a good carb for a streetported 12a. or even a streetported 13b. Going to do both.

REVHED 01-13-02 03:58 PM


Originally posted by Audio Science
So would the 44idf be a good carb for a streetported 12a. or even a streetported 13b. Going to do both.
It think the main difference between the IDA and IDF is that the IDF has a balance screw and was designed for use in multiple carb setups. It also has a different mounting bolt pattern so I'm not sure if you can get manifolds for them. Get an IDA. That's what I'm doing.

BadAssRX-7 01-13-02 11:03 PM

well paul clamed 200 on a good streetported motor with a f.f exh. im sure thats flywheel. I would most deff. get a yaw carb it i did a lot of stop and go and street driving. i had a dellorto 48 on my streetported 12a with all the toys i dynoed 165@ wheels after LOTS of tuning... i wound up selling as it as a pita @ 5280 feet. im now getting a dual downdraft 36mm weber. im not sure what the carbs are ida idf what not. i know its a r.e. setup. a friend of mine had this same setup on his stock ported 12a with 120k on it and 0-45 he killed my streeported dellorto 48 but after 45 it was on, i think alot to do with that was the ported motor.

peejay 01-13-02 11:09 PM


Originally posted by BadAssRX-7
well paul clamed 200 on a good streetported motor with a f.f exh. im sure thats flywheel. I would most deff. get a yaw carb it i did a lot of stop and go and street driving. i had a dellorto 48 on my streetported 12a with all the toys i dynoed
keep in mind, that "over 200hp" was with his E-Production setup, which includes an extensively modified intake manifold as part of the package, and I'm told the package costs in the neighborhood of $1400, and you've got to send your (disassembled) engine to him for him to get the intake manifold ideally ported. makes a 48ida look downright cheap! BTW on another forum I learned the reason it makes more power than the 48ida is because the 48ida is required to use fairly small venturis in E-Prod... on the street where there are no rules you can go bigger for more power.

Besok 01-14-02 01:28 AM

weber
 
i have a 48mm ida weber on my 12a it goes hard!

i only have small mods - extended port and a 3inch exhast.

it puts out 130 rwhp

the only thing i dont like about it is the fuel econ (lets not continue with that)
and the flat spot between 3500 and 4000, but thats mainly cause its setup for track.

pics here

RXcetera 01-14-02 07:45 AM

Besok, I need your dash! Do you know of any wreckers around Sydney that would have that exact dash (RHD, brown w/speaker holes)???


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