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Hi Guys

 

I was just thinking the other day when looking at my brothers Alfa- romao

 

Is it possiable to dual carb an ea82

 

How i imagine it is a hitachi carb sitting directly above each inlet port, one on either side if the engine. i.e. without the inlet manifold, would this work?

 

i have very little knowlege of mechanics or carbs but i was just curious??

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Guest taprackready

Yes, it would work but I don't know anybody who's done it. Air cooled VW's have run those setups for more years than most of us have been alive.

 

Bill

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I'd think you'd want to run some kind of crossover tube anyway. Having owned a dual-carbed Austin-Healey Sprite, I can tell you from first hand experience that tuning and syncing two carbs that can't see each other is a COMPLETE PAIN IN THE BUTT! :banghead:

 

Then again, those were SU carbs and were a pain anyway...

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I'd think you'd want to run some kind of crossover tube anyway. Having owned a dual-carbed Austin-Healey Sprite, I can tell you from first hand experience that tuning and syncing two carbs that can't see each other is a COMPLETE PAIN IN THE BUTT! :banghead:

 

Then again, those were SU carbs and were a pain anyway...

I'll strongly agree with the first part, and mildly disagree with the second. You probably will want the crossover, and the throttle linkage and synchronization are likely to be a pain.

 

The SUs really weren't THAT bad... probably a better choice than most regular carbs for the British applications. And they did give us excuses to tinker...

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I've thought about dual carbs for the ea82 before. It really wouldn't be too hard to fab up some little "mini-manifolds" to bolt 'em up there.

 

Then I asked myself, "Why?" For the time and effort used to make something up and get it to work properly, you could swap in an EA82T or EJ22. I used to be a hardcore carbs-only fanatic, until my carburetor started having problems. That's why I'm going to put SPFI on my car in about a month. If one carb has given me this much trouble, I don't really want to think about two of them:rolleyes: .

 

There is also the issue of intake port size. Those ports are REALLY tiny. Are the factory heads capable of flowing enough air to make this worthwhile?

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I'd think you'd want to run some kind of crossover tube anyway. Having owned a dual-carbed Austin-Healey Sprite, I can tell you from first hand experience that tuning and syncing two carbs that can't see each other is a COMPLETE PAIN IN THE BUTT! :banghead:

 

Then again, those were SU carbs and were a pain anyway...

I'm pretty much with Scooby/NorthWet on this one, crossover tube/balance pipe is a very good idea. And I find the SU on my Zcar (with balance pipe) fairly easy to tune, but then again I've been tuning dual carb VeeWees for years.

Side note: successfully tuning duals normally requires a flow sync tool or a good ear.

As for duals on the subie, like Bill said, look at the VWs, with some custom manifolds you should be able to use any of the single throat carbs that they use (or spread bores with turbo subie heads). Since the displacement, ports and valves are of similar proportion the jetting should be pretty close to start.

Gary

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My Triumph (car) and Datsun SSS wagon were both dual-SU'd. My bro's A-H 3000 had 3 of those... we had a couple flow-synch tools (mental block! I can't remember the name of tool.) ... still got at least one.

 

My Honda (bikes!) had multiples, with the 750 and the 400F having four... I had a quad-mercury-column flow tool for those... much better than the UniSyn... HEY! I remembered!!! :headbang:

 

After 30 years of futzing with carbs, I would go with either SPFI of MPFI... and prob play with the MegaSquirt for that. Cheap, and I get to play Diety!

 

Speaking of futzing with carbs... use to have a pair of Weber 40DCOEs on my 510, but, amongst other foibles, the carb floats used to not. Funny thing about 510s: The top of the fuel tank is higher than the carbs. Maybe add a little slant from parking downhill... I changed my oil ALOT!!!

 

If I had to do over, I would go EFI.

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They're rare, but you can get dual-carb EA81s here in Australia. I believe they were factory spec for Rally etc.

 

You could probably use the manifold from one of these as a template for what you'll need on the EA82, and you'd probably be able to use the dual carbs from it.

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Romeo,not romao.....but what I want to know is are you talking about a dual Weber set up from a euro-Alfa?There were several kits around here for them.I know of one artist up in the hills who has the set up NEW still in the box.He wasted his Spider and it probably still sits banged and beaten next to his barn.

 

Much more throatier sound using the Webers over the FI that came on the Alfas.

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I have dealt with dual carbs on aircooled VWs. (I have owned over 40 aircooled VWs........I have an addiction problem) Webbers, Delortos and Solex PDSITs. Summary: PAIN IN THE @ZZ! You must keep them syncronized or you end up with one half of your engine running different than the other. No fun.

 

The only advantage to running duals as opposed to one large carb, is that you shorten the intake. The closer you can get the fuel delivery device to the intake valves, the more efficient (and powerful) your engine. Throttle response is greatly increased as well. That was before the days of the wonderful invention known as MPFI.

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Well-I'm a old Dual-carb school person--Please no flames, but I'm setting up a dual 40mm Dellorto set on the EJ22 going into T-Rex (and no, I'm not using ANY electronic parts other than a dizy--mechanical advance only--). For sheer guts-out-in-your-face, you can't beat multi-carb set-ups:grin:, and I like the set-up (yea, I know---I'm CRAZZZZY)--So--YES on a Balance tube--the bigger, the better--you want the carbs to "swap" gas:brow:--the bigger the tube, the less you need to syncro the carbs--they should be the same as much as possible of course. And a GOOD dual carb set will run very close to a multi-port FI system--you just need to know HOW to set them up RIGHT---

 

So that's my two cents worth---

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whats a su carb? is that a brand name? heard of solex and webber but not this su before.

Well-In the collection of useless data--I have a answer for this one--------

are you ready------

 

 

 

 

 

 

 

Skinner's Union--and why they would make carbs--any guesses??

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thanks for the replys guys

as i am a student, i do not have the money or current knowlege do perform this operation just as yet, but it may be something i can do in the future.

 

does a dual carb setup decrease fuel ecconomy much???

 

will it effect any of the vaccum devices or emmission systems???

 

is this how it would be set up???

 

| | | |

| |_______| |

| _______ |

_| |_______| |_

/ \

| ea82 |

\_______________/

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well I know of one board member that was planning on doing a Dual Kadron (I sold the set I had to him and he should be getting to them hopefuly soon cause it has been what 3 years now? and they are solex carbs for those that were/are not veewee heads lol) and for syncronizing them they are easy and keeping them there too same as with Dellortos (the best carb out there and bummer they don't make them anymore :( be perfect for the subie) but webers they are very troublesome when sat up for dual carbs and you need to be a swiss watchmaker to make sure they are defanatley sync'd together

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I recently looked into doing it, and i spoke to my local Autocraft. These guys seem to be the subaru gurus in my area, and they have tried a few dual carb setups, but due to the tiny intakes on the ea82 heads, they managed to get - technically speaking - bugger all power, for a hell of a lot of money spent on parts and tuning. I definitly would look into sp/mpfi.

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Hey DJBob, is that Autocraft in Collins street?

 

They used to be up in West Hobart didn't they, alfa and lancia lovers.

I really need some specialist help with my twin carby set up.

If they are good I will give them a try,

Barry Cooper charged me $155 to tell me I had a split diaphram in my vacuum advance (which they didn't fix ) and to adjust my tappets, I could have done that in 15 minutes!!

I don't think they even touched my carbs.

I drove for three hours for that!

S..ts me no end!

If you cannot plug the magic computer into a car these days, the highly paid mechanics look blankly at you, I knew what was wrong and even told him, but my car came back running worse.

Sorry to vent.

TB

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