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Hey all,

First time posting here, but have been lurking for a while. I had a 1990 Civic dx I was going to k swap, but ended up getting an 02 RSX Type-S for $800 and would rather restore this for a fun daily instead of the civic.

Body wise, the car is pretty great. The only rust was on the passenger rear quarter, and barely starting. I'm taking care of it currently, and will be repainting the car once all body work is done. I need to source a new front bumper, and possibly a rear. The front is a terrible looking aftermarket thats held on by 2 screws, the back is oem, but has paint cracking and fading, and doesnt seat completely correct, possibly a broken tab? It was missing its spoiler (holes were capped), but I was able to pick up an oem spoiler for it and put it on.

The transmission and clutch are in great shape, engine is not. Car came with what appears to be a Takeda intake, Acuity shifter kit, some form of lowered springs or coilovers (they're red in appearance but I have yet to get a good look).

I bought this off of a kid who owned it for exactly one week. He drove 130 miles to buy the car, drove it home, and when he got home it overheated and he parked it, never turned it back on until I came to buy it and drive it up a tow truck bed. He had a mechanic cousin come check it out and found coolant in the oil cap, said it was a bad head gasket.

When I inspected everything, I did notice the milky residue under the oil cap, as well as the coolant reservoir being black with oil. I'm assuming the engine will need a full rebuild, as I doubt I'd get away with just replacing the head gasket, flushing the engine with a few oil changes, and flushing the radiator and lines.

Do you guys think it would be better to rebuild my k20a2, or find another engine to put into it? I do not have hondata or kpro, but if I can find a cheap z1 or z3 and itll work with my trans/ecu, I'm open to it. I've also considered a jdm k24a2, as I've found a good one shipped for about 1k.

Once I've got my engine situation figured out (any input on rebuild vs replace vs swap is appreciated, or if anyone knows any good shops in SE michigan/detroit to take my car to, I'm open to it, as I have no room to pull an engine here), and my body work done, I plan to handle brakes and suspension work before repainting and any power mods. However, I will post pics of the car and all progress/updates as I go along.

I'd appreciate any wisdom, or advice on what to check for and make sure of as I go through this.
 

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Arouse the DAMPFHAMMER!
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Welcome @MAG-s at K20a.org.

Do you guys think it would be better to rebuild my k20a2, or find another engine to put into it? I do not have hondata or kpro, but if I can find a cheap z1 or z3 and itll work with my trans/ecu, I'm open to it. I've also considered a jdm k24a2, as I've found a good one shipped for about 1k.
If you want to keep this cheap, go with the JDM K24A engine. But be carefully, there exists no K24A2 in the JDM, only K24A and there exists an ECO and a PERFORMANCE variant of these (40 hp difference!), which you only can rate looking under the valvecover and if not cheated rated on the IM and head casting mark. But once again, be very carefully with advertised JDM K24A2, only USDM had the K24A2!
 

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Discussion Starter · #3 ·
If you want to keep this cheap, go with the JDM K24A engine. But be carefully, there exists no K24A2 in the JDM, only K24A and there exists an ECO and a PERFORMANCE variant of these (40 hp difference!), which you only can rate looking under the valvecover and if not cheated rated on the IM and head casting mark. But once again, be very carefully with advertised JDM K24A2, only USDM had the K24A2!
Sorry, I probably shouldn't be making forum posts early in the morning LOL. I did mean a JDM k24a out of an accord sport. 200hp, 160ish tq, 7100 or 7300 rpm redline, which is similar to the USDM k24a2.

I'm not necessarily worried about cost, but the more affordable something is obviously the easier it is to work with. I'd like to keep driving characteristics similar to how it is stock; the 8k RPM redline is important to me, so I'd prefer not giving any of that range up. I have read that with kpro you can adjust the redline on the k24a to 8k, but I've also heard there are issues with reliability if you do this.

My end game power goal is going to be around 230whp NA, maybe higher but not much. I'm more interested in upgrading and tuning my handling, braking, etc. Need a motor to be able to do anything though, and I'm having a very hard time finding k20a2's anywhere. I've found some clean k20z3 engines for around 1300, and the k24a for 1k shipped. I've also found k20a type r motors for 2k in good shape, so I'm not sure what my best option is. I've called a dozen shops around Detroit today, and not a single one of them wants to touch an engine rebuild, or they dont know much about Honda motors. Without having garage space to do a rebuild, I think I'm going to be stuck having to swap engines no matter what.

If I do, I won't able to buy kpro for a couple weeks, and I'd rather not drop a motor in just to kill it due to a non matching ecu or something stupid. If there are any members around the area who want to help, I've got enough beer to go around😂.

If I do go the k24a route, I'll need to get a CR-V mounting bracket, correct? Will my transmission have any issues with pairing up? I know in most cases of k20xx swaps in the RSX chasis, you'll have to move over your water pump, AC/PS/ETC pulleys, Intake, etc. If I did get the k24a, would it be more beneficial to use the head from my k20a2?

About to get initial pics uploaded, and maybe take some pics of the engine bay to see if anyone else notices something I'm missing.
 

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Sorry, I probably shouldn't be making forum posts early in the morning LOL. I did mean a JDM k24a out of an accord sport. 200hp, 160ish tq, 7100 or 7300 rpm redline, which is similar to the USDM k24a2.
For your JDM motor, make certain you're getting a K24a from a 2002-2008 Honda Accord Type-S or a 2009-2013 Honda Accord Type-S. The 2002-2008 comes with 197HP and 171 lb-ft of torque. The compression ratio for these models is 10.5:1. The 2009-2013 models came with 203HP and 171 lb-ft. and the compression ratio is 11:1. The cylinder head on both of these should be stamped RBB. The camshafts should be specific for the RBB cylinder head. You want VTEC engagement on both the intake and exhaust side.

I'm not necessarily worried about cost, but the more affordable something is obviously the easier it is to work with. I'd like to keep driving characteristics similar to how it is stock; the 8k RPM redline is important to me, so I'd prefer not giving any of that range up. I have read that with kpro you can adjust the redline on the k24a to 8k, but I've also heard there are issues with reliability if you do this.
Upgrade the stock oil pump from the K24a to the Type-S pump from your existing motor, if it's still in good condition. This will allow your 8K redline. K-Pro will be your adjustment parameter for this, although it's not recommended to go past 8200 rpm on the K24 block. It's been done safely before but for reliability and longevity stand points, don't exceed this rpm.


If I do go the k24a route, I'll need to get a CR-V mounting bracket, correct? Will my transmission have any issues with pairing up? I know in most cases of k20xx swaps in the RSX chasis, you'll have to move over your water pump, AC/PS/ETC pulleys, Intake, etc. If I did get the k24a, would it be more beneficial to use the head from my k20a2?
Yes, you'll need the CRV post mount : 11910-PPA-000. Your 6 speed RSX-S transmission will bolt up to the JDM motor without issue. Use your existing accessories from the K20a2 for your K24a. This will be your water pump, coolant passage, alternator, ac compressor, etc. If you want to make power with the K24a, swap on an RBC intake manifold and use your K-Manager software in K-Pro to adjust for the upgrade. Utilize the oil cooler from your existing motor on the K24a. There are several write ups on how to make this work but you must use the coolant passage from your stock motor. Yes, it would be very beneficial to use the K20a2 Type-S head on your K24a. It out flows the K24a head by a bit more CFM and has upgraded valve springs and retainers. Use the K20a2 head for sure.

Anything else, just ask. This is a great community and lots of people here to help. Welcome to the forum,

-G
 

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Anything else, just ask. This is a great community and lots of people here to help. Welcome to the forum,
These are facts.

The USDM 06-08 K24a2 from the TSX comes with PRB single valvesprings At the same time the switch went from the 01-04 PRB dual valve springs to the single valvespring.

This makes me want to PN# cross match to see if the JDM 02-08 Accord Type S, has the PRB valvespring. The valvespring retainers went under a newer design for strength on the outer edges of the retainer.

With my build, I am using AP1 F20C1 outer valvesprings and PRB inner valvesprings. I am attempting to use Supertech Ti retainers if 4Piston thinks it is a good fit, if not I will use PRB steel retainers.
 

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Discussion Starter · #6 ·
For your JDM motor, make certain you're getting a K24a from a 2002-2008 Honda Accord Type-S or a 2009-2013 Honda Accord Type-S. The 2002-2008 comes with 197HP and 171 lb-ft of torque. The compression ratio for these models is 10.5:1. The 2009-2013 models came with 203HP and 171 lb-ft. and the compression ratio is 11:1. The cylinder head on both of these should be stamped RBB. The camshafts should be specific for the RBB cylinder head. You want VTEC engagement on both the intake and exhaust side.

I figure I'll just post a specific link here for that motor I mentioned, just in case this doesn't end up being the right one. I appreciate you all being so willing to help out and point me in the right direction, despite the incorrect terms. Still taking in information, and realizing theres a lot of little things I need to keep a close eye out for.

Upgrade the stock oil pump from the K24a to the Type-S pump from your existing motor, if it's still in good condition. This will allow your 8K redline. K-Pro will be your adjustment parameter for this, although it's not recommended to go past 8200 rpm on the K24 block. It's been done safely before but for reliability and longevity stand points, don't exceed this rpm.
If I can hit 8k on here to match my cluster, I'd be content with it, but I do like the fact that the k20a/a2/z1/z3 can be made to rev above 8k, into the 9k range. I realize to a lot of people this is arbitrary as they'd rather have power than rev range, but I prefer that kind of characteristic, so I'm still more inclined to go with a k20a/a2 or something else unless it doesnt make any economical sense.

Yes, you'll need the CRV post mount : 11910-PPA-000. Your 6 speed RSX-S transmission will bolt up to the JDM motor without issue. Use your existing accessories from the K20a2 for your K24a. This will be your water pump, coolant passage, alternator, ac compressor, etc. If you want to make power with the K24a, swap on an RBC intake manifold and use your K-Manager software in K-Pro to adjust for the upgrade. Utilize the oil cooler from your existing motor on the K24a. There are several write ups on how to make this work but you must use the coolant passage from your stock motor. Yes, it would be very beneficial to use the K20a2 Type-S head on your K24a. It out flows the K24a head by a bit more CFM and has upgraded valve springs and retainers. Use the K20a2 head for sure.

Anything else, just ask. This is a great community and lots of people here to help. Welcome to the forum,
Thanks for the part number! That'll make it easier to find, and I can definitely swap most things over, or just buy replacements if needed. I'm not sure if my radiator is going to be savable or if I'll need to replace that, or at least the hoses given the oil being mixed into the coolant in the reservoir as well. I appreciate the help a lot!
 

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Arouse the DAMPFHAMMER!
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Sorry, I probably shouldn't be making forum posts early in the morning LOL. I did mean a JDM k24a out of an accord sport. 200hp, 160ish tq, 7100 or 7300 rpm redline, which is similar to the USDM k24a2.
Thanks for your reply, that's good and that is what I wanted to recommend.
 

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Discussion Starter · #9 ·
Thanks for your reply, that's good and that is what I wanted to recommend.
I may end up going this route since this is looking to be the fastest/most viable path, however, even after the swap it wont run until i have kpro to flash my ecu with, correct? Should i consider replacing all my accessories instead of swapping them over?

Additionally, what should i do woth the k20a2 after? Would i use the head from this or the k24?
 

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Arouse the DAMPFHAMMER!
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KPro (cable throttle) or FPro (DBW TB) help to control some of the functions (emission, engine, safety). It helps but is not stop when not having it. The K20A2 I would use as source for head swap and oil pump swap.
 

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Discussion Starter · #11 ·
KPro (cable throttle) or FPro (DBW TB) help to control some of the functions (emission, engine, safety). It helps but is not stop when not having it. The K20A2 I would use as source for head swap and oil pump swap.
I believe the k20a2 transmission, manifold and throttle body work, or should work, but have heard i'd need to use the k20a2 head, or an adapter for the k24a manifold. I may be wrong, but I saw something about this in some earlier forum posts. So I'd be using kpro, but based on your post, chances are I could drive the car with the engine until it arrives and I can adjust parameters, so lomg as i dont push it past 7k until i can adjust settings?

I've found a complete type r motor for 2k, as well as a completely rebuilt bottom end (just needs gasket, my k20a2 head) k20a2 for the same price. Should I consider either of these over the jdm k24a?
 

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Arouse the DAMPFHAMMER!
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run until i have kpro to flash my ecu with, correct?
As long as you use the original engine and ECU you will only see differences outside the closed loop cycle, which is when load increases over 80 %. Differences would be created by header, exhaust muffler and your intake system, which all may look different to the original. This would work, but can be lead to serious damage to your engine by excessive use of WOT. On the other hand if you run the stock everything, it will be no issue at all to run the stock ECU beside immobilizer and some other chassis bounded functions if you swap into a different chassis, which I actually not aware off.

FYI: to flash is a term one would only use with FPro, which is a flash process of the chip itself to change the real calibration. KPro is an emulator board, which alters according the uploaded calibration the original Honda calibration.

heard i'd need to use the k20a2 head, or an adapter for the k24a manifold.
The K20A2 head comes with better flowing ports compared to the K24A2 head ports and support more torque and power for your setup. In that case the stock ECU is no longer a good way, it would strongly be recommended to tune it.

k20a2 for the same price. Should I consider either of these over the jdm k24a?
You still see the decision from a money point. I see your decision from a power curve standpoint. The K24A2 supplys the higher torque curve, which stops earlier at the same power level as the smaller displacement engine K20A2.

For me the K20A2 is always more fun to drive, because it revs 800 rpm higher at the same mean piston speed. I revved my stock longblock 86x86 engine to 8800 rpm on street which means a lot of race feeling and noise (mostly). Of course the K24A2 would take the money pit faster from A to B if the task is WOT only because the higher torque curve translates to have more power below 7000 rpm over the revving band.
 

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I've found a complete type r motor for 2k, as well as a completely rebuilt bottom end (just needs gasket, my k20a2 head) k20a2 for the same price. Should I consider either of these over the jdm k24a
Yes... straight up and down like six o' clock get that over a jdm k24a.... IT CAN NOT BE A ECO K20a engine from lesser model. ONLY the jdm DC5 Type R K20a, red valve cover, PRC intake manifold.

If you have the opportunity to ask what was the cause fo the bottom end (shortblock) rebuild / service, get the reason and let us know.
 

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I figure I'll just post a specific link here for that motor I mentioned, just in case this doesn't end up being the right one. I appreciate you all being so willing to help out and point me in the right direction, despite the incorrect terms. Still taking in information, and realizing theres a lot of little things I need to keep a close eye out for.
I don't think that motor is the one you'd want. With the RAA casting on the cylinder head, I believe that signifies it's from a lower spec JDM Accord and not the Type-S version. You want the RBB casting on the cylinder head, this indicates that it's for a 3 lobe cam setup - the performance VTEC that's most desirable. Someone correct me if I'm wrong...

-G
 

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Discussion Starter · #15 ·
Yes... straight up and down like six o' clock get that over a jdm k24a.... IT CAN NOT BE A ECO K20a engine from lesser model. ONLY the jdm DC5 Type R K20a, red valve cover, PRC intake manifold.

If you have the opportunity to ask what was the cause fo the bottom end (shortblock) rebuild / service, get the reason and let us know.
I went to go check both listings today, and both are now sold, after sitting for literal months. I should've just acted on the k20a, but it's all good! I've found another for around 2500, however it has a grey valve cover. Engine block is a k20a and listed as a type r engine, so I'm not sure what the deal with that is. Otherwise, I've seen k20z1's, which I believe shouldn't be a difficult switchover, but they're on the more expensive end. I could get a k20z3 with ecu and transmission for around 3000. The k20z3 is good power and relative to what the type s has anyway, but the gearing is a bit better in the z3's transmission, and it has the bonus of an LSD already installed, but beyond that I'm not sure what, if anything would need to be switched over from the a2 block, or if it would end up being a complete changeover.

I don't think that motor is the one you'd want. With the RAA casting on the cylinder head, I believe that signifies it's from a lower spec JDM Accord and not the Type-S version. You want the RBB casting on the cylinder head, this indicates that it's for a 3 lobe cam setup - the performance VTEC that's most desirable. Someone correct me if I'm wrong...

-G
I've seen both versions, the red/white top and the grey top, and I'm more inclined to believe you're correct, as generally the high spec versions have a red cover, or some variant that gives signification its not their run of the mill engine.


My biggest priority is getting a new engine in so the car can be driven. I'd like to keep the swap as simple as possible, as I'll either be doing this out on the road, or paying a shop to swap it for me. In the case of the latter, I'm not the most inclined to trust a random shop to swap an entire engine/trans/ecu. I can deal with programming Hondata/kpro myself once I get the box in, and I can take note of the parts that have been already added on to my engine when I got it, that may be worth keeping. Weather was bad today, so I wasn't able to get out to get more pictures of the engine bay, but will do so in the morning.

Going to be looking for a new bumper soon in the meantime, what are the biggest things to look for when buying an oem one off someone?
 

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Going to be looking for a new bumper soon in the meantime, what are the biggest things to look for when buying an oem one off someone?
Look for the bumper to have OEM Honda stamping on the backside of it. You should see the following part number or portions of the following part number:

04711-S6M-A90ZZ (Model years 2002-2004)

04711-S6M-A91ZZ (Model years 2005-2006)

Look out for the S6M portion of that part number to be printed somewhere on it. That portion signifies the part is for USDM spec Acura RSX models.
 

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Discussion Starter · #17 ·
Look for the bumper to have OEM Honda stamping on the backside of it. You should see the following part number or portions of the following part number:

04711-S6M-A90ZZ (Model years 2002-2004)

04711-S6M-A91ZZ (Model years 2005-2006)

Look out for the S6M portion of that part number to be printed somewhere on it. That portion signifies the part is for USDM spec Acura RSX models.
Thanks! I'm gonna save that 02-04 model number to reference when looking.
 

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to me it looks like the passenger side engine mount might need to be replaced. I could be wrong, check it out to see if the the mount's rubber is compromised.
 
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