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HiPo EA81 build to start soon


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A few on here know that im planning a high performance build of an EA81 soon. Im not going to let too much out of the bag yet except to say that it will be running Dual carbs on a JDM dual carb manifold. Here is the question though. I want to run dual webers but the only way that i see them fitting is if i use one 32/36 DGEV (normal subaru weber conversion) and one 32/36 DFEV (the miror image of the DG). The reason for this would be so that the float bowls would be on the outside and give enough room for the carbs to be mounted on the intake. Would this be a good idea though and could i rejet them enough to run correctly? I was looking for smaller 2 barrels or even two big one barrels but the limitation is on the space between the carbs. There is not much on the dual carb manifold.

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I'm not sure this is something you would be interested in, but here is a unusual source for small one barrel carbs. Maybe mount them directly above the intake ports on a short custom manifold?

 

http://www.corvair.com/user-cgi/catalog.cgi?

function=goto&catalog=MAIN&section=MAIN&page=57

 

The old 140 horse Corsa used 4 Carter or Rochester one barrel carbs on a 164 cubic inch (2.6 liter) 6 cylinder.

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The 32/36 would not be a good choice due to it's progressive linkage - it would be difficult to get both secondaries timed just right and I think you would have a nightmare of a time getting all the transitions correct. They can be modified for simultaneous linkage, but the different barrel sizes will play havoc with tuning them. I think you would be better off going with two single-barrel carbs or even something like the 38 DGAS.

 

Why not drop the manifold and just bolt a carb to each head? You would need to fab a coolant cross-over and a way to do hook in the upper radiator hose but that's doable...

 

GD

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The 32/36 would not be a good choice due to it's progressive linkage - it would be difficult to get both secondaries timed just right and I think you would have a nightmare of a time getting all the transitions correct. They can be modified for simultaneous linkage, but the different barrel sizes will play havoc with tuning them. I think you would be better off going with two single-barrel carbs or even something like the 38 DGAS.

 

Why not drop the manifold and just bolt a carb to each head? You would need to fab a coolant cross-over and a way to do hook in the upper radiator hose but that's doable...

 

GD

 

I had thought about that as well but that would be going into the realm of a bit more work than i want to take on. That would involve two completely custom intakes with the coolant crossover. I have also thought about just using the hitachis and either diving in and rebuilding them or getting them rebuilt by a shop. The intake that i have a line on has two hitachis on it still but the need rebuilding from sitting around so long. I could also just do the single 32/36 but i want a bit more eye candy under the hood lol.

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I have to wonder if you could adapt a set of linked 2bbl Kadron carbs from an aircooled 1.8L VW motor.

 

My 67 Ghia had them and that little car screamed at WOT after the dual carb setup was installed.

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I have to wonder if you could adapt a set of linked 2bbl Kadron carbs from an aircooled 1.8L VW motor.

 

My 67 Ghia had them and that little car screamed at WOT after the dual carb setup was installed.

You did just give me a good idea to look at what VWs are running for dual carbs since they are about the same displacement. I found this:

 

http://cgi.ebay.com/ebaymotors/Weber-Dual-24-24-Carburetor-VW-Intake-Chrome-Filter_W0QQitemZ120461198447QQcmdZViewItemQQptZMotors_Car_Truck_Parts_Accessories?hash=item1c0c0c046f&_trksid=p4506.c0.m245

 

I did not even know that these existed. I wonder how well they would perform on the top of the dual carb manifold. Also is it just me or is there no choke on either of them?

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They are Brazilian crap in his exact words :lol: Good thing i didnt bid on em.

 

Weber's are made in Spain. Does he mean they were built for the Brazilian VW market or something?

 

As far as I know, no Weber's have ever been produced in south America.

 

I don't see any issue with a 24/24 design but a larger single barrel would be easier and simpler to tune.

 

You can do a LOT even with a 32/36. I have been engaged in the development of a turbo-charged Suzuki Samurai using one - in fact the carb is one I rebuilt and ran myself for a couple years before passing it to a co-worker. Make no mistake - this is NOT a good carb to use for a blow-through turbo setup - but he's a determined and pig-headed individual and after many months of tuning and about a dozen times on my wide-band setup he's got it going OK. You can't imagine the problems he's had.... in the process we both learned a TON about the carbs and how air-bleed and emulsion tubes interact etc. It was an amazing learing experience but you definitely want something simpler if you are planning on running twin carbs.

 

GD

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Im not sure exactly what he meant other than that they were not genuine weber carbs and that there was no aftermarket for them. The are some knockoffs that probably wont perform as well as i would like. After getting off the phone with him it sounds like the best idea for power would be doing two larger single barrels mounted above each head. So maybe custom manifolds are not out of the question just yet.

 

Also those 24/24s dont have a choke...i need a choke.

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Heres a question for everyone....if me and a friend of mine were able to come up with a design for manifolds that mount the carbs above the heads..and were able to price them right would there be a market for them? Would people be interested? Not saying that will happen or not im just trying to get some feedback.

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what about sidedraughts?

 

i ran triples SU 's on a 3.3l 6 cyl in OZ and made it go like a bat out of hell:banana:

they use them on minis in pairs too

 

SU's or SD strombergs even sidedraught webers - not sure of their avail in North America but they are plentiful in oz for the holden red 6

still req custom manifold....

 

but you want eye candy......:banana::banana::Flame:

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I'd definitely be interested. Would like it to be rather accepting of adaptors though because I can't say I know what I'd run on it.

Yes that would be the big question because everyone wants to run different carbs. I would have to find out what would be the most popular carb out of the many 1 barrel carb options. I myself was looking at a 34 ITC weber but they are $. The dual Kadrons would work too. I dont think it would make sense or be doable to make a carb mount for all the carbs unless they are very similar between the 1 barrels. And it def would not make sense to make all different mounts.

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