Honda / Acura K20a K24a Engine Forum banner

21 - 40 of 41 Posts

·
Registered
Joined
·
66 Posts
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.
 

·
Registered
Joined
·
457 Posts
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.
The numbers after the RBB-(#) on the heads are more for a reference of around when the head may have been made/machined (like a batch number) and not directly related to a specific year.
However, you RBB-3 maybe have just been from a newer car compared to a RBB-1 head.

Having said that, ALL 'JDM K24A' engines (with VTEC on both cams) are all comparable to 04/05 K24a2 USDM engines.
 

·
Registered
Joined
·
66 Posts
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.
 

·
Registered
Joined
·
457 Posts
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.
Yes the injector bases are the same but the 06-08 intake/plenum part is bigger. My cousin actually did this swap on his Accord as well (Swapped Accord intake manifold to 06+ TSX intake manifold & J37 TB) and it was very responsive compared to the Accord. He also did a comparison between stock throttle body and J37 (with tsx manifold on stock accord engine) and it was night and day. We are both actually in the process of doing Built K24a2 with RSP heads.
Just throwing this out there, if you don't have the 06+ tsx manifold already, he would gladly sell to you as he's buying my RBC off of me and I'm moving on to a bigger manifold.
 

·
Registered
Joined
·
66 Posts
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.
 

·
Registered
Joined
·
12 Posts
Pardon me from threadjacking but I didn't want to create another thread for this. I'm new to the site and I've been looking at K24s in the market and it seems like JDM K24A are the most common rather than the TSXs nowadays (i'm from US). Assuming I ended up with a High Comp RBB JDM K24A, aside from disabling the VTP for the JDM K24A, what else do I need to change to make it run like a stock TSX engine?
 

·
Registered
Joined
·
66 Posts
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.
 

·
Registered
Joined
·
12 Posts
Thank you very much! Please correct me if my understanding is wrong.

So I have a blown K20A3 EP3 which prompted me to upgrade to K24 and all I can find as of the moment are the JDM K24s. My question is, can I use all the accessories I have from my K20A3 and should fit the JDM K24 no problems, correct?
 

·
Registered
Joined
·
1 Posts
Okay guys, I'm in need of some schooling.
I come from the euro world and have done full engine teardowns and rebuilds as well as swaps. I'm in the US and recently came into an 06 JDM Odyssey Absolute 4WD. I'm trying to get up to speed on the K24a engine for mods and etc to keep this RHD bad boy as my daily. Can a home definitely say which model block/head/intake manifold came in the 06 Odyssey Absolute or do I have to get it up on a lift to poke around for stamps?
Also, for future reference, which car should I be using for US parts searches that will mostly fit my engine? Sounds like a few of the aux components from the US are different.
Appreciate the guidance!
-Brohnson
IMG_20200722_134041.jpg
 

·
Registered
97 civic HX K24a
Joined
·
1,258 Posts
Okay guys, I'm in need of some schooling.
I come from the euro world and have done full engine teardowns and rebuilds as well as swaps. I'm in the US and recently came into an 06 JDM Odyssey Absolute 4WD. I'm trying to get up to speed on the K24a engine for mods and etc to keep this RHD bad boy as my daily. Can a home definitely say which model block/head/intake manifold came in the 06 Odyssey Absolute or do I have to get it up on a lift to poke around for stamps?
Also, for future reference, which car should I be using for US parts searches that will mostly fit my engine? Sounds like a few of the aux components from the US are different.
Appreciate the guidance!
-Brohnson
View attachment 102284
US equivalent for parts would be the Acura TSX K24a2’s 👍
 

·
Registered
Joined
·
3 Posts
Still a 200hp k24a engine but yes i believe its not revamped like the later -2 -3 engines
Late to the party but I really need some advice I need to replace my early Rbb2 and have a replacement late rbb2 that I was told may or may not work,I can get an rbb1 for a good deal is the rbb1 same as early rbb2? Any help is appreciated
 

·
Registered
Joined
·
457 Posts
Late to the party but I really need some advice I need to replace my early Rbb2 and have a replacement late rbb2 that I was told may or may not work,I can get an rbb1 for a good deal is the rbb1 same as early rbb2? Any help is appreciated
I have an RBB-3 2007 tsx cylinder head if you want it.
What people don't understand is the 06-08 tsx cylinder heads come with the PRB/ valve springs from the RSX Type S. Those valve springs are visually larger than the 04-05 tsx engines and all jdm K24A valves. They are similar to the S2000 valve springs which are labeled with part number PCX. Seats would be different IIRC.
 

·
Arouse the DAMPFHAMMER!
Joined
·
7,530 Posts
What people don't understand is the 06-08 tsx cylinder heads come with the PRB/ valve springs from the RSX Type S. Those valve springs are visually larger than the 04-05 tsx engines and all jdm K24A valves. They are similar to the S2000 valve springs which are labeled with part number PCX.
Thanks for your information, which I really appreciate @DaSlowestCL9.

It sounds plausible to me, as the valve size was increased at the K24A2 '06+ engines as well as the valve lift curve was adapted. Taking another out of the shelf, which can keep up with the increased forces, would plausible to keep development costs for the revised valve and valve actuation concept.

Seats would be different IIRC.
Do you mean the valve spring seat or the valve seat?
 

·
Registered
Joined
·
3 Posts
I have an RBB-3 2007 tsx cylinder head if you want it.
What people don't understand is the 06-08 tsx cylinder heads come with the PRB/ valve springs from the RSX Type S. Those valve springs are visually larger than the 04-05 tsx engines and all jdm K24A valves. They are similar to the S2000 valve springs which are labeled with part number PCX. Seats would be different IIRC.
Im curious if the 06 08 head will work on a 04 block because of the difference will be use inch stock 04. Cams thanks for the help
 

·
Registered
Joined
·
457 Posts
Thanks for your information, which I really appreciate @DaSlowestCL9.

It sounds plausible to me, as the valve size was increased at the K24A2 '06+ engines as well as the valve lift curve was adapted. Taking another out of the shelf, which can keep up with the increased forces, would plausible to keep development costs for the revised valve and valve actuation concept.

Do you mean the valve spring seat or the valve seat?
Yes, the only difference cam wise is the intake cam revision and +1mm oversize intake valve.
I just checked the part numbers and the S2000 uses the same valve seats.
 

·
Registered
Joined
·
457 Posts
Im curious if the 06 08 head will work on a 04 block because of the difference will be use inch stock 04. Cams thanks for the help
Yes the 06-08 head will work just fine. I've had both 04/05 and 06-08 head castings side by side and the casting is exactly the same. It's amazing how much an intake came revision and oversized intake valve could wake up an engine.
 

·
Arouse the DAMPFHAMMER!
Joined
·
7,530 Posts
...It's amazing how much an intake came revision and oversized intake valve could wake up an engine.
About how much hp or lbft do we speak about? Would be great if you have dyno graphs to that experience and would share it here.
 

·
Registered
Joined
·
457 Posts
About how much hp or lbft do we speak about? Would be great if you have dyno graphs to that experience and would share it here.
Hondata did a stock tuning comparison over 10 years ago but the link is dead now. This is all I was able to find for comparison with minor mods for a k24a2 Hondata tsx tuning
The tuning potential with the 06+ tsx cams IMO, almost defeats the purpose of a Drop In Cam or a Drag Cartel 2.2 cam. The 06+ tsx cam gives great midrange torque and decent top end HP when fitted with the 50* VTC.
 

·
Arouse the DAMPFHAMMER!
Joined
·
7,530 Posts
The tuning potential with the 06+ tsx cams IMO, almost defeats the purpose of a Drop In Cam or a Drag Cartel 2.2 cam. The 06+ tsx cam gives great midrange torque and decent top end HP when fitted with the 50* VTC.
Would be great to see that. I agree the DC 2.2 promote the higher end, while the midrange normally shows a bigger dip around VTEC (bad compromise of idle quality and top end power cam design, a bit to extrem). So it might be attractive to have just a super smooth and proper low and midrange torque and a bit of disadvantage at the top for DD cars. But some dyno verification would be good. Maybe one of the guys stored it?
 
21 - 40 of 41 Posts
Top