Swapping a K20Z3 or a K20Z1 head on a K20C2

madmax1698

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So I've been thinking lately about how nice the 8th gen Si and the RSX type-S sounded when accelerating and crossing over into Vtec.

Knowing that the 8th gen Si/RSX type-S and the 10th gen base engine a somewhat the same bottom-end, would it be possible to swap a head from the old Si/RSX type-S onto the 10th gen's K20? The only thing that might prevent the swap being reliable is the different compression ratios (11:1 for the Si/RSX type-S vs 8:1 for the new Civic).

I know that the K20Z3 head and K24 block has been done a few times and well documented on the forums, but what about this swap?

If it's possible to do it, any ideas on the power figures?

I'm pretty sure no one is going to actually do it because there is a 10th gen Si and CTR available, but what if money wasn't an issue, is it doable?
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xcoreflyup

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So I've been thinking lately about how nice the 8th gen Si and the RSX type-S sounded when accelerating and crossing over into Vtec.

Knowing that the 8th gen Si/RSX type-S and the 10th gen base engine a somewhat the same bottom-end, would it be possible to swap a head from the old Si/RSX type-S onto the 10th gen's K20? The only thing that might prevent the swap being reliable is the different compression ratios (11:1 for the Si/RSX type-S vs 8:1 for the new Civic).

I know that the K20Z3 head and K24 block has been done a few times and well documented on the forums, but what about this swap?

If it's possible to do it, any ideas on the power figures?

I'm pretty sure no one is going to actually do it because there is a 10th gen Si and CTR available, but what if money wasn't an issue, is it doable?

Totally doable it. It is the time commitment that will challenge you. If you work a full time job, this will easily be a 6 months to a year long project. You might as well do a manual swap if you have a CVT.
 

swah_fk7

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So I've been thinking lately about how nice the 8th gen Si and the RSX type-S sounded when accelerating and crossing over into Vtec.

Knowing that the 8th gen Si/RSX type-S and the 10th gen base engine a somewhat the same bottom-end, would it be possible to swap a head from the old Si/RSX type-S onto the 10th gen's K20? The only thing that might prevent the swap being reliable is the different compression ratios (11:1 for the Si/RSX type-S vs 8:1 for the new Civic).

I know that the K20Z3 head and K24 block has been done a few times and well documented on the forums, but what about this swap?

If it's possible to do it, any ideas on the power figures?

I'm pretty sure no one is going to actually do it because there is a 10th gen Si and CTR available, but what if money wasn't an issue, is it doable?
Completely different engine. Nothing will line up on the head as they are completely different engines. The only thing they share in common is the K in the name.
 

mvela

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So I've been thinking lately about how nice the 8th gen Si and the RSX type-S sounded when accelerating and crossing over into Vtec.

Knowing that the 8th gen Si/RSX type-S and the 10th gen base engine a somewhat the same bottom-end, would it be possible to swap a head from the old Si/RSX type-S onto the 10th gen's K20? The only thing that might prevent the swap being reliable is the different compression ratios (11:1 for the Si/RSX type-S vs 8:1 for the new Civic).

I know that the K20Z3 head and K24 block has been done a few times and well documented on the forums, but what about this swap?

If it's possible to do it, any ideas on the power figures?

I'm pretty sure no one is going to actually do it because there is a 10th gen Si and CTR available, but what if money wasn't an issue, is it doable?
Actually the new k20c2 has a 10.8:1 compression ratio
 

mvela

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What I would like to know is how hard it would be to build a K20c3 from a K20c2. They sound more similar than a c1 or c4. The c2 and c3 have the same compression ratio along with the same Vtec engagement. The c3 sounds like a turbocharged version of the c2.
 


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What I would like to know is how hard it would be to build a K20c3 from a K20c2. They sound more similar than a c1 or c4. The c2 and c3 have the same compression ratio along with the same Vtec engagement. The c3 sounds like a turbocharged version of the c2.
i looked all over trying to find part numbers for k20c3 engine internals and came up with nothing so i couldnt verify if they have the same internals or not, if they did have the same internals that would be a dead giveaway that the k20c2 can be safely turbo'd to atleast 270 hp.
 

mvela

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i looked all over trying to find part numbers for k20c3 engine internals and came up with nothing so i couldnt verify if they have the same internals or not, if they did have the same internals that would be a dead giveaway that the k20c2 can be safely turbo'd to atleast 270 hp.
That’s exactly what I trying to figure out:hmm:
 

charleswrivers

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The only parts I’ve heard successfully swapped have been intake manifolds from Ws and throttle bodies off of another... I think a Z. Though the specs of a C2 is roughly similar to an A3 which served as the base RSX engine and 7th gen Si engine, like was mentioned before... I think other heads are incompatible. It’s be cheaper/easier to do a swap to a K20A2 or do a K24A1 swap most likely. Even if they haven’t been in a CivicX, the swaps have been done in earlier cars many times. I had both A2 and A3 powered cars and the A3 was a very good engine but didn’t hold a candle to the A2 over ~5500 RPM... where the magic happened. I had my 9th gen 3 years but the K24Z7 never grew on me like the earlier K20A2 did.
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