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Head swap


Sheppyman
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depends what 1.8 you're talking about.

 

 

all EJ series heads are interchangeable. so if you're talking about putting EJ18 heads on an EJ22, yes, it definitely will work. and it'll bump your compression up a bit (start running premium gas!).

 

if you're talking about EA-series 1.8s.....no. no way.

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I have a bad valve on my 2.2 but have two 1.8's that are good.

How would changing the gasket help with it?

if it lowers the comp. that means the displacement is different? would it lower it to the 2.0 comp.?

Why would I change the distrubuter?

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ignore the distributer comment, not applicable.

 

technically, yea, the smaller quench volume of the 1.8 heads will change your displacement, but only by about 8ccs. Also, I think standard EJ22s already use the thicker headgasket, so you could only increase the compression ratio by changing the gasket.

 

stock 2.2 compression ratio is 9.5:1. I think 1.8 heads brings it to like 10.5 or so. should make for some sweet torque, but you'll need to run premium gas to prevent detonation.

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depends what 1.8 you're talking about.

 

 

all EJ series heads are interchangeable. so if you're talking about putting EJ18 heads on an EJ22, yes, it definitely will work. and it'll bump your compression up a bit (start running premium gas!).

 

if you're talking about EA-series 1.8s.....no. no way.

 

I've been wondering that for quite a while. So I could theoretically put STI heads & intake on a EJ22T SOHC motor?

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I've been wondering that for quite a while. So I could theoretically put STI heads & intake on a EJ22T SOHC motor?

 

easy. as far as the head-to-block mating, yes.

 

 

as a general rule, intake mani has to match the heads (there are exceptions, in this case, 1.8 and 2.2 are interchangeable). also as a general rule, heads from larger-displacement engines have a larger quench volume, and vice versa. so swapping around will effect compression. also, using heads for a much larger bore can cause issues with the headgasket mating surface (I have heard of issues with N/A 25D heads on 18s to be specific).

 

 

 

capn_r. *my understanding is* the quench volume of the heads *technically* effects the volume of the overall combustion chamber. but it's only a couple ccs each, so it's not enough to substantially effect the displacement (for example, a 2.2l is 2212 ccs, with 1.8 heads, it's probably 2204). but at TDC, it's a substantial change, so noticeably effects the compression ratio.

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Not trying to threadjack or beat a deadhorse here but, are there any other differences between the ej18/22 heads? Valve sizes/porting, or cam profiles? Just curious if there's some optimum combo of head/cam/gasket to run on a na-ej22. Thanks, Spencer

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