3A-S head gasket

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tercle
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My tercel:: 1985 SR5
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3A-S head gasket

Post by tercle »

Will the standard 4WD Tercel head gasket work on a 3A-S head?
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Petros
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My tercel:: '84 Tercel4wd w/extensive mods
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Re: 3A-S head gasket

Post by Petros »

it should, I think all the 3a long blocks (low end with head) are the same.

is the 3a-S from an import motor? post a picture of the gasket face if it is off the head.
'87 Tercel 4wd SR5 (current engine swap project)
'84 Tercel 4wd (daily driver, with on going mods)
'92 Mazda MPV 4wd (wife's daily driver)
'85 Tercel 4wd DLX auto(daughter's daily driver)
'01 Honda Civic (other daughter's daily driver)
tercle
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Joined: Sat Aug 27, 2011 9:57 am
My tercel:: 1985 SR5
Location: Seattle

Re: 3A-S head gasket

Post by tercle »

I don't have it yet, so no picture.
Thinking of buying it.
From what I've read here, it is a from a Japanese Market engine
It has those weird vanes on the intake ports, but it doesn't have the link (or any of the links) to keep the vanes pointed the same way.
It says 3A-K20X on the valve cover
oldfaithful
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My tercel:: 1984 Tercel 4WD

Re: 3A-S head gasket

Post by oldfaithful »

Same headgasket, but the valve cover and cover gasket are different, they're not straight on the intake/exhaust side of the head,they are the same as some of the 4AC Motors.
tercle
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My tercel:: 1985 SR5
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Re: 3A-S head gasket

Post by tercle »

I took a couple pictures at lunch, but forgot to take one of the gasket surface.

Image

Image
tercle
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Re: 3A-S head gasket

Post by tercle »

Will the camshaft fit a 3A / 3AC head?
Is it the same camshaft or a different grind?
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Petros
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My tercel:: '84 Tercel4wd w/extensive mods
Location: Arlington WA USA

Re: 3A-S head gasket

Post by Petros »

that what those are for, I have seen blank bosses like those on some of the imported 4ac engines. I wonder what the vanes do? to improve performance the ports and valves need to be larger, vanes would direct the flow to where? low speed/high speed? keeps the port velocity up for better low end performance? they did that on the early 4age, two intake runners per oversized ports, one closed off at low speed, and both open at higher speed. Keeps the port velocity up at lower speed for slightly higher torque below about 4000 rpm. Hardly seems worth the complexity, they abandon it on the later versions of the 4age, so must not be that helpful.

Simplest thing to do would be to just fix them to the full open position. I would take them out and just plug the holes.

it would not be hard to rig it so you can control it with a pull cable like the old manual choke cable.

The head gasket should not be affected at all. I have rebuilt a 4ac with the same bosses, but without the system in place, it was blanked off. it only affects the valve cover as noted.

I wonder if you can get the fuel system that came with that engine, it has to be better than the USDM choked down two barrel.
'87 Tercel 4wd SR5 (current engine swap project)
'84 Tercel 4wd (daily driver, with on going mods)
'92 Mazda MPV 4wd (wife's daily driver)
'85 Tercel 4wd DLX auto(daughter's daily driver)
'01 Honda Civic (other daughter's daily driver)
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