EA81 Dual Port Head Valves

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Matt
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EA81 Dual Port Head Valves

Post by Matt » Sun Jun 13, 2010 1:31 pm

Does anyone know where you can get EA81 Dual Port Head Valves from? As i have burnt some exhaust valves and i believe they are a different size and strength? Or what exact Australian Delivered model cam out with dual port heads? I believe that Targa Top Brumby's did come out with them but i could be wrong.

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Matt
"Bianca"
'86 Brumby - Dual Port Heads, 5 Speed Dual Range, Custom Cam, Tuned Weber, Tuned Suspension, 2" Body Lift Kit, LSD, 14" rims, 2.25" Exhaust, Snorkel, Dual Batteries, DVD Player, UHF, VHF, etc. Offically now part of the 350, 000 km Club! :) And still pulling like a freight train.
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"Claudia"
82 MY Wagon - EA81T, RS Liberty WIAC, 5 Speed Dual Range, Tuned Suspension, 14" Rims 27" Tyres, 2" Body Lift Kit, Apline Head unit, UHF, Roof Console, L Series seats, Soon to have New Paint, snorkel, Dual batteries, etc
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spike
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Post by spike » Sun Jun 13, 2010 3:26 pm

i seem to think that dual ports where specially cast by sub4??

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TOONGA
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Post by TOONGA » Sun Jun 13, 2010 3:40 pm

Subaru made what is called a dual port head for its twin carb EA81 motor, and yes the valves are different for this motor (as is just about everything else)


as for getting new valves the only place I could suggest is subaru Japan :(

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RSR 555
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Post by RSR 555 » Sun Jun 13, 2010 3:54 pm

Have you tried this site? Chris Rogers posted it earlier :)

https://www.subarupartsdepot.com/oem-subaru-parts.html
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Matt
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Post by Matt » Sun Jun 13, 2010 4:08 pm

I just had a play with that site and i am going to need a year and model number to find the valve part number. Thanks anyway RSR 555.

And i will go to talk to my engine rebuilder mate on tuesday, he might be able to match something up. I really need to find a year and model of MY Subaru that came with a dual port standard so i can track it that way.
"Bianca"
'86 Brumby - Dual Port Heads, 5 Speed Dual Range, Custom Cam, Tuned Weber, Tuned Suspension, 2" Body Lift Kit, LSD, 14" rims, 2.25" Exhaust, Snorkel, Dual Batteries, DVD Player, UHF, VHF, etc. Offically now part of the 350, 000 km Club! :) And still pulling like a freight train.
Image


"Claudia"
82 MY Wagon - EA81T, RS Liberty WIAC, 5 Speed Dual Range, Tuned Suspension, 14" Rims 27" Tyres, 2" Body Lift Kit, Apline Head unit, UHF, Roof Console, L Series seats, Soon to have New Paint, snorkel, Dual batteries, etc
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coxy
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EA81 dual port valves

Post by coxy » Sun Jun 13, 2010 7:11 pm

Try Competition Valves Australia,Motec and Competition Valves started up together in the same back shed many years back with Richard bendell and John White from memory,last time I had some made exhausts were $45.00 each but that was some time ago.
Even then at $45.00 each that was much cheaper than BMM r 100 valves at $200.00 each.
Google should find them as they supply most of the Aussie SuperTaxi race teams as well.

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Gannon
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Post by Gannon » Sun Jun 13, 2010 8:32 pm

No EA81 ever came with dual port heads, but i assume that you are referring to the heads which have the exhaust port divider all the way to the surface of the exhaust port and the exhaust and intake valves reversed.

This is a dual port head, available only on the EA62
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The exhaust ports were on the front and rear of the engine, as opposed to the bottom
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They had completely separate exhaust ports (one per cylinder in a similar fashion to a VW engine)
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The EA81 heads you are referring are better described as hi flow heads
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Matt
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Post by Matt » Sun Jun 13, 2010 8:57 pm

Thanks Coxy i will look them up.

Suparoo that is an awesome looking idea, it would be interesting to see one in the flesh that is for sure. And yes i am talking about the reversed exhaust valve EA81 which i have heard always been called a dual port head as the ports are separate until they leave the engine so to speak.
"Bianca"
'86 Brumby - Dual Port Heads, 5 Speed Dual Range, Custom Cam, Tuned Weber, Tuned Suspension, 2" Body Lift Kit, LSD, 14" rims, 2.25" Exhaust, Snorkel, Dual Batteries, DVD Player, UHF, VHF, etc. Offically now part of the 350, 000 km Club! :) And still pulling like a freight train.
Image


"Claudia"
82 MY Wagon - EA81T, RS Liberty WIAC, 5 Speed Dual Range, Tuned Suspension, 14" Rims 27" Tyres, 2" Body Lift Kit, Apline Head unit, UHF, Roof Console, L Series seats, Soon to have New Paint, snorkel, Dual batteries, etc
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coxy
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Post by coxy » Sat Jun 19, 2010 11:52 pm

Yes there are quite a few variations and information is patchy at best and downright inaccurate at worst regarding what Subaru heads actually are.
Dual port EA81 is actually Dual exhaust ports as the exhaust valves are located at the extremities of the head and in the head they are fully divided.
They do share a common exhaust header.
The biggest advantages of these heads are the exhaust heat is not concerntrated in the centre of the head until well away from the combustion chambers,and most importantly the inlet porting whilst siamesed is pretty much a downdraft almost straight shot at the back of the valve head.
Normal EA81 inlet ports are a long S bend configuration,not good for flow,as are incidentally the EA81 tyrbo heads,these are not in any way related to the Twin Carb EA81,the fact the Twin carb heads do have the exhaust fully isolated until the manifold gasket does mean they are dual port and dual outlet,just side by side at the outlet into a common header pipe.
Placement of the injector bosses in the turbo heads shows they are not the reverse valve heads as some may have assumed,but use the standard EA81 inlet layout
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steptoe
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Post by steptoe » Sun Jun 20, 2010 1:05 am

EA62 and 63 were in what, and what were these heads in. were these special or standard for these engines. weber inlet too!

the ea81t head is interesting, first look for me. injector on head squirts right at valve i suspects

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