Honda / Acura K20a K24a Engine Forum banner

1 - 10 of 10 Posts

·
Registered
Joined
·
1 Posts
Discussion Starter #1
I’m doing research in what it takes to turn a k20z3 into the K20A found in the FD2. I know there are better ways to make more power, that’s not my goal. I’m trying to learn and have a nice project around, and hoping I can reuse the block and head. Also I’m in California, so if I can make extra power and sneak it pass CARB and cops great.

Anyways, are the heads in all K20 engines the same? The k20a and z3 part numbers for the head are different.

Also, is there a left hand drive equivalent steering rack used in the FD2 (hydraulic type)?

Thanks!
 

·
Premium Member
Joined
·
10,376 Posts
Short list is, head, cams, piston, oil pump, intake manifold, throttle body, crank pulley.

Not sure what you mean by steering rack.
 

·
Arouse the DAMPFHAMMER!
Joined
·
6,265 Posts
Welcome to K20a.org SFTifoso!

Anyways, are the heads in all K20 engines the same? The k20a and z3 part numbers for the head are different.
Like drtye listed, a lot of different and very expensive parts on the OEM aftermarket. About which engine year do we talk about? There are at least three versions of the K20A engine available.

You can use a lot of OEM parts, only a few guys at CARB would know the right combination of parts as at least the IM changed from PRC to RRC and wasn't the EURO R having the RBC IM? I am not sure about it. I have great respect of the CARB guys, which have a responsibility to carry. But none of them knows all variants of each engine. So it is very likely to find one who find nothing wrong with an different combination. Emissions can be tuned by tuning, especially on the CARB measurement points.
 

·
Registered
Joined
·
263 Posts
Got lost Them Witches. Could you explain it what you mean with that "AP1 PCX valvetrain" here?
I’m doing research in what it takes to turn a k20z3 into the K20A found in the FD2. I know there are better ways to make more power, that’s not my goal. I’m trying to learn and have a nice project around, and hoping I can reuse the block and head. Also I’m in California, so if I can make extra power and sneak it pass CARB and cops great.

Anyways, are the heads in all K20 engines the same? The k20a and z3 part numbers for the head are different.

Also, is there a left hand drive equivalent steering rack used in the FD2 (hydraulic type)?

Thanks!
The k20a May have a PRB OR an RSP coded cylinder head depending on which car it came out of.(Type R version only ) I believe the “rbc “k20a are the equivalent to usdm k20a2 or z3. I don’t see how they would know at CARB that your z3 has type R cams and pistons etc it’s still all oem stuff
 

·
Arouse the DAMPFHAMMER!
Joined
·
6,265 Posts
I don’t see how they would know at CARB that your z3 has type R cams and pistons etc it’s still all oem stuff
They won't recognize it if they don't prove the part numbers and markings on the cam. It is even for K-series guys not normal to see the difference without checking documentation to that. He just need to tune it correctly for CARB emission testing.

PCX Is the head code for s2000 👍
Thanks man for clarification.

@Them Witches could you please explain what you mean by "transform to a AP1 PCX..."? Never saw anyone doing it that way. The F20C1 guys do it normally vice versa, move the K-valvetrain to the F-head because of the cam phasing technology (VTC of iVTEC).
 

·
Registered
Joined
·
263 Posts
They won't recognize it if they don't prove the part numbers and markings on the cam. It is even for K-series guys not normal to see the difference without checking documentation to that. He just need to tune it correctly for CARB emission testing.

Thanks man for clarification.

@Them Witches could you please explain what you mean by "transform to a AP1 PCX..."? Never saw anyone doing it that way. The F20C1 guys do it normally vice versa, move the K-valvetrain to the F-head because of the cam phasing technology (VTC of iVTEC).
Wow I never knew that. The head head gaskets are supposed to be the same and I’ve read the theory of the S2k cylinder head on a k series block but never knew the valvetrain was exchangeable between f20c and k20. Seems like that would be a popular way to go
 

·
Arouse the DAMPFHAMMER!
Joined
·
6,265 Posts
Wow I never knew that. The head head gaskets are supposed to be the same and I’ve read the theory of the S2k cylinder head on a k series block but never knew the valvetrain was exchangeable between f20c and k20. Seems like that would be a popular way to go
Oh, sorry, there is maybe a misunderstanding here. I meant the VTC mechanism is attractive for the F20C1 engine, which have only the VTEC system, but not the cam phaser system VTC. There was a F20 project where the owner added the VTC mechanism to the F20 head. This is huge fabbing effort, no plug and play swap.

BTW, there is no single cause to use the F20C1 head on a K-series block. Less midrange torque, loss in driveability and response. It is not granted to gain top end torque by the bit better flowing head, which easily can overtaken by some modifications on the K-series port. The bigger valves on the F20C1 are not helpfully for many applications and engine setups. This design was done for higher engine speed, a 87 mm bore and a VTEC-only-engine. A transfer of that casting to a K-series is no upgrade for all, it is mostly a down grade, not worth the effort. The K-series head ports are one of the best mass production ports of the 2 Liter class. The F-series is good in flow numbers, but it's application is written between the lines of 36 mm inlet and 31 mm outlet valve size = only high revvings allowed 😉. You know why RWD guys, even S2000 guys, use a K-series plant? Yeah, better everything 💪.
 
1 - 10 of 10 Posts
Top