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anyone have definite knowledge of JDM K24A motors? mine has RBB-2 head, Raa Intake?

90910 Views 55 Replies 19 Participants Last post by  LotusElise
Does anyone have any real knowledge of the JDM K24a? It seems there are many different models from what I've seen (I searched and couldn't find anything definitive regarding the JDM TSX equivalent).

The one I bought has an RBB-2 head, with the 3 lobe cams (I checked it).

But the intake manifold is stamped RAA? (I can't tell if its the tsx rbb size or smaller\) nothing to compare to.)

And the block is stamped RAA on it.

What motor is this from and how much power does it make? I can't tell if the JDM RAA manifold is smaller than the US RBB because I don't have an RBB to compare to. Can someone take a measurement of the RBB intake chamber part and let me know how tall it is? If it's a small Accord-type manifold then I'll switch it out and buy a tsx one (going in a sandrail so I'm looking more for torque than top-end power).
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That’s what you want. I just picked up a JDM K24a as well. Paid $850 which seemed fair for how complete it is. The head on mine is stamped RBB-3. in doing my research prior to my purchase there was some miss information that some RBB-2s and all RBB-3 heads were the same as the US 06-08 K24A2 with the updates. That does not seem to be the case as I measured the TB intake opening and it’s just over 60mm not the 64mm like the 06-08.
Agree, do you think an 06-08 TSX manifold would bolt up to my RAA base? Very easy to swap that part and cheaper to only buy the actual intake without the injector base if they are the same.
I have access to one already just not sure it’s going to be worth the extra cost for the manifold and adapter plate. I am going to run this thing totally stock and it should make enough power that I will probably have to detune it a bit to stay in class anyway. Just exploring options should I need some extra lo cost HP.

be curious to see before and after dyno charts of a motor that had the 04-05 manifold swapped to an 06-08 to see what it really does without the larger valves and cams.
I will try to help as I went through this for the last four months shopping for US based K24A2s. From what I have learned the JDM 24A is basically the same as the 04-05 US TSX motor. The difference is the alternator and water pump housing are unique to the JDM motor. So you need to get those if you don’t have them already. i got my housing from a junk yard CRV with the K24A and my alternator is from a RSX base model because that’s the harness I am using. There are lots of threads on the TB and that really depends on if your doing cable or drive by wire. Hope that helps some and others may know more than I on this, this is just what I have learned.
K24a with RBB-2 or RBB-3 head is 197hp same as USDM 04-05 tsx. All k24 blocks share the RAA casting stamp as far as I know.
per the Wiki this isn’t exactly right on the JDM K24a from the Odyssey.

it shows the RBB-2 makes 187 while the RBB-3 makes 203. also shows the RBB-2 has slightly lower compression.

I don’t think people have dug into and documented the differences like the USD K24a2 has had. Amazing with how many are out there.
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