4ac cylinder head on a 3ac block?

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Chevro
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My tercel:: 1984 2wd
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4ac cylinder head on a 3ac block?

Post by Chevro »

Is it possible? Has it been done? Is it worth it?

Thanks

-Chevro
GTSSportCoupe
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Re: 4ac cylinder head on a 3ac block?

Post by GTSSportCoupe »

The only difference between the two blocks afaik is the cylinder bore. Same chunk of iron otherwise.
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Neu
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Re: 4ac cylinder head on a 3ac block?

Post by Neu »

Yeh, it can be done.

It's pretty common to switch heads on toyota engines, the R series do it all the time. 22r block, 20 r head gasket, with an 18r head gasket, raises compression and the engine runs pretty well.
Typrus
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Re: 4ac cylinder head on a 3ac block?

Post by Typrus »

They are identical heads according to my super-accurate side-by-side-mo-tron comparisons. Lol. I saw no obvious differences.
RIP 10-07- 1984 Toyota Tercel SR5 4wd Wagen 6 speed

RIP 04-05- 1986 Toyota Tercel SR5 4wd Wagen 6 speed

1st Terc- 1987 Tercel SR5 4wd Wagon 6-speed, Sadly cubed

1985 Tercel Standard 4wd Wagon w/ 3-speed auto, Living a happy life in Boulder last I knew
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Petros
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Re: 4ac cylinder head on a 3ac block?

Post by Petros »

are the valve head diameter the same too? It would be great if the heads fit but the 4a head had bigger valves.
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Typrus
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Re: 4ac cylinder head on a 3ac block?

Post by Typrus »

Part no. V5107 and V5106, int and exh respectively on 3AC... and 4AC. Same part number, same part, no size difference.
RIP 10-07- 1984 Toyota Tercel SR5 4wd Wagen 6 speed

RIP 04-05- 1986 Toyota Tercel SR5 4wd Wagen 6 speed

1st Terc- 1987 Tercel SR5 4wd Wagon 6-speed, Sadly cubed

1985 Tercel Standard 4wd Wagon w/ 3-speed auto, Living a happy life in Boulder last I knew
Chevro
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Joined: Mon Sep 22, 2008 6:34 pm
My tercel:: 1984 2wd
Location: Eugene OR

Re: 4ac cylinder head on a 3ac block?

Post by Chevro »

So, it sounds to me like it can be done, but there's no reason for it.

Thanks
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