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School me on EA81 DUAL-CARB engines


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  • 2 weeks later...

Can somebody tell me whether the Y-pipe for these engines is the same as for any of the other engine models around that era? I have an EA81S just about out of rebuild but I don't have the correct Y-pipe.

 

I'll probably have to get one made but I thought I'd ask around first - thanks in advance.

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Nah unfortunately the Y for the dual carb engine was different. The normal y-pipe "should" bolt right up however but you will be leaving a bit of power on the table. If you can spring for it and find a good exhaust shop, you can get a nice Stainless y pipe bent up for your car. I had one made for my former coupe along with a full Stainless exhaust.

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  • 1 year later...

Factory Twin Carb Subaru EA Engines were available on both the EA71 (1600) and EA81 (1800), Both engines were defined by a following "S" at the end on their engine codes. This was Subaru's way of calling it the Sports model. The engines were a completely different design to the standard models. The "S" models had Dual Ports and Opposite Valve configuration, which means different cams and rocker gear.

 

They were available in Japan in the Subaru Leone GSR and in the later RX Models. These engines has Higher Compression Ratio and had ~10% more power output. They were used heavily in the late 70s and early 80s Rally cars.

 

 

 

 

 

 

WorthlessWithoutPics.gif

 

 

Do you Mean like This? (this is an EA71):

 

100_4119.jpg

 

 

100_4121.jpg

 

 

I've seen such conversions, even done to EJ engines:

 

2104061330094569859S425x425Q85.jpg

 

 

Usually done for VolksWagens

 

IMG_0895-1.jpg

 

 

 

 

Yes!

 

 

 

Yes, it is this:

 

e.jpg

 

 

safari-1.jpg

 

 

safari-2.jpg

 

 

And this are Photos of the Car on the 1983 Safari Rally Race:

 

Safari1.jpg

 

 

safari-4.jpg

 

 

safari-3.jpg

 

 

safariengine.jpg

 

When Subaru Developed that Head-Mounted Twin downdraft Weber Carb EA81 engine with Reversed Valves, they already had the Turbo EFi Technology, so very Few of those were made, since Subaru started to sell the "Turbo Traction" Models in the same 1983 year...

 

 

subaru_1983_turbo_brat.jpg

 

 

TurboTraction.jpg

 

 

But very Few Twin Weber Carb Models were Available for Sale, mainly in Japan and New Zealand,

 

like This one, which was for sale some months ago:

 

 

Portapapeles01-7.jpg

 

 

I'll Love to Own one of those Later Twin Carb RX!

 

Kind Regards.

Hello mate,

Would you,please,to pass me photos(and other infos) from the EA engines with twin carbs,mainly WEBER?

I have in mind to make an EA71 engine with twin carbs,for rally use.

Any other advice concerning special parts for more power is welcomed.

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Sorry for the Photos not being viewable, but that only happens the last week of each month, as I reach very Quickly the Monthly Bandwidth assigned to my Decade old "Free Account" as I Explained here:

 

~► http://www.ultimatesubaru.org/forum/topic/139920-photobucket-sucks-a-rant-about-picture-hosting-woes/

 

Also there I explained a way to bypass that limit... So, you can either wait for the monthly bandwidth assignment to be resetted, or use this:

 

~► http://3.hidemyass.com/ip-12/encoded/Oi8vd3d3LnVsdGltYXRlc3ViYXJ1Lm9yZy9mb3J1bS90b3BpYy8xMzE1NzEtc2Nob29sLW1lLW9uLWVhODEtZHVhbC1jYXJiLWVuZ2luZXMvcGFnZS0y&f=norefer

 

I hope this works for you,

Kind Regards.

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The biggest difference with the Dual carby heads is the reversal of the inlet and outlet valves (on the true Dual carb heads) do yours have 2 inch or bigger exhaust ports? and a visible separator on the inlet port making 2 D's

 

as for available information all I can give is that I owned one of these motors for a few years. sadly I sold the car as I moved country (wish I never had now) And when I came back to Australia the car had vanished along with the motor :(

 

Inlet and outlet clearances are the same, not sure if you will need solid or hydraulic lifters, mine had solid.

 

Mine was mated to a 3.9 ratio straight cut 4 speed dual range box (came with the motor) and I was able to tune it to get between 95-100 km/h out of second gear.

 

Timing was set at 8 degrees any less and the motor ran like a chaff cutter, any more and it pinged its little head off.

 

they are a fantastic motor and will rev way higher than the normal EA81.

 

you will be amazed :)

 

TOONGA

Mine seem to be original RX as a complete engine with carbs manifold and even Air filter assembly but the divider is actually in the exhaust ports not the intake, The valves are reversed etc so I do not think there would be two versions of this engine Should take some photos and upload them as I have the heads off at the moment.

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You can upload them to a photo hosting website, such like Photobucket, Facebook, etc... then once you view the photo there, do a right click over the photo and copy its URL address, then come to do a post here, you'll see in the Tools of the post window, a small green square, under the A and the :) ... hit it, a dialog box will appear, then erase the http:// that the dialog box has, and paste the the copied URL address of the Photo.

 

That will display the photo here.

 

Kind Regards.

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Nope, the 1983 Subaru RX had a Special Version of the EA81S with limited edition Twin Weber Carbs, Subaru stopped the production of these because they already were selling the Turbo EFi EA81 (1983), that Twin Weber Carb setup were used only at the Safari Rally, at New Zealand and very few were sold to the public.

 

 

665318_464228950289805_1741320724_o.jpg

 

Kind Regards.

Edited by Loyale 2.7 Turbo
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  • 1 year later...

Seems nobody else noted that the cylinder head in the Competitive RX brochure is actually a Modified Standard valve type head not the EA 81 S reverse valve style head as used on the Manatee racecars, Look at the front head shown in front of the car where the combustion chamber is visible and it is clearly obvious from the chamber shape that the larger inlet valves are on the outside as with the standard type heads.

 

Another giveaway is that the spacing for the Weber IDF carbs lend themselves to a modified standard head as is currently done by some of the Experimental Aircraft Engine Builders in the US, What with the reverse valve EA 71 S and 81 S type engines having the inlets closely spaced together which works well for the stock manifold setup but does not work so good with dual throat Webers.

 

Seems that those Subaru Engines were in fact pre group A proper and likely homologated under Group 4 regulations in a similar way to that done by Nissan with the "Violet GT" variant of the Nissan PA HA 10 series Stanza or new 510 as it was known in the US.

 

Nissan homologated the LZ 20 B type four valve twin cam with such a model run of 200 vehicles supposedly available in Jamaica ( Yeah Right Not Likely) Ford also did something similar with the Escort RS 2000 but in Germany they actually did supply the parts namely a twin IDF Webers setup and better cast iron exhaust manifold in boxes in the boot of the new car when purchased from a Ford Rallyesport dealership with intentions for a Competition life for the vehicle again for Homologation purposes.

 

It is clearly visible in the post just under the Blue VW with the EJ engine where the Cylinder Head next to the driving lights shows a standard type combustion chamber with Inlet Valves in standard configuration not as with the reverse valve S type Engines.

Here is a Nissan LZ 20 B engine, Subaru likely did something similar when it came to the good bits, Not really available except as competition bits and then probably only for the "right drivers".

 

LZ20B ready To Go

Edited by coxy
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the spark plugs have little choice but to be down there somewhere where they would be in the standard head I would think. And Coxy, talking to a Kiwi fabricator who was around the big names at the time - still is,, but this side of the ditch - told me Subaru sold the rally Safari stuff. Again, a guess , was probably to anyone who had the money and the desire to have something that was not likely streetable, all those many years ago !

 

It is a bit like here with a manifold and triple webers to suit the Ford 2V250 heads - been available for at least thirty years just don't know how many they have sold - never seen one in the flesh !

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