whats the best choice in a k24a/k20a?

[Jums]

iv been researching about the k24/k20 frank and came up with several questions.. is the only thing different between a TSX's k24a2 and the CRV's k24a4 the cylinder head? are the k20a2 heads same as the JDM k20a heads? do u get more power if u destroke the 2.4L wen u put on the k20a head? if u were to drop that frank in, wat else do u need other than the gearbox, computer?

[barefootbonzai]

don't think you've researched enough.

[heist]

don't think you've researched enough. :thumbsup:

[Jums]

ne recommendations where to search? bcause i still cant find if the difference btween a k24a2 and a k24a4 is just in the head.. ne info would b much appreciated.

[sivic]

try k20a.org for all your k series questions.

[aaronng]

ne recommendations where to search? bcause i still cant find if the difference btween a k24a2 and a k24a4 is just in the head.. ne info would b much appreciated.
Search those import tuner websites. Here's a little hint though. k24a2 has vtec on the intake and exhaust cams, while the k24a4 has it only on the intake cam. k24a2's crankshaft and pistons are lightweight and forged.

And.... changing the head alone does not change your engine from a 2.4L to a 2.0L

[Jums]

lol yea i know that but som sites explains the benefits of a k20 head on a 2.4L block and on som sites it explains destroking the 2.4L into 2.2L givs u more power.

[sifoo]

And.... changing the head alone does not change your engine from a 2.4L to a 2.0L

So why int he world would you want to buy a k24 in the first place just to destroke it to 2.0 :thumbdwn: :thumbdwn: :thumbdwn:

[Paul1985]

Here you go:

http://www.k20a.org/forum/showthread.php?t=13433

and this is also helpful..
http://www.k20a.org/upload/Kserieschart.htm

Search k20a.org you will find stacks of info on this swap :)

[Paul1985]

If you read that guide carefully i gave you, you will see that doing a frank on a k24a4 will result in valve clearance issues.

The best frank setup IMO is a K24a2 with a K20a/K20a2 head. Im not sure on which trans would be best for this setup either.

[destrukshn]

So why int he world would you want to buy a k24 in the first place just to destroke it to 2.0 :thumbdwn: :thumbdwn: :thumbdwn:
it's like some people putting a b16 head with a b18 block.

[Jums]

thanks alot for that paul1985 mate ! much appreciated ! :D

[aaronng]

So why int he world would you want to buy a k24 in the first place just to destroke it to 2.0 :thumbdwn: :thumbdwn: :thumbdwn:
Back after a long hiatus.
The k24a2 has an electronic throttle which can't be used with an aftermarket ECU. So the trick is to use a k24a2 and put on a k20a2 head. It still keeps the 2.4L but now the engine is open to the full range of aftermarket ECUs for the DC5R/RSX-S. That means turbo with proper engine management is possible as well.


If you read that guide carefully i gave you, you will see that doing a frank on a k24a4 will result in valve clearance issues.

The best frank setup IMO is a K24a2 with a K20a/K20a2 head. Im not sure on which trans would be best for this setup either.
With the k24a2, you can use any k-series trans. What is not known however is whether the speed sensor would still work properly (or even fit).


lol yea i know that but som sites explains the benefits of a k20 head on a 2.4L block and on som sites it explains destroking the 2.4L into 2.2L givs u more power.
The k24a2/3 is a good block. The stroke is too long at 99mm, so it is not able to rev to high RPMs, even if it was sleeved. A destroked k24a2 to 2.3L on the other hand can rev to 9400rpm and makes 184.7kW at the wheels (it's in a Lotus Elise in the US). http://tsx.acurazine.com/forums/showthread.php?t=29759

[Paul1985]

With the k24a2, you can use any k-series trans. What is not known however is whether the speed sensor would still work properly (or even fit).

With that link i posted earlier it mentions you cant use a K24 tranny on this swap as there currently arent any mounts on the market for it (not sure how true this is).

But heres a graph where many different K-series tranny's are compared:
http://www.k20a.org/forum/showthread.php?t=7317

[aaronng]

With that link i posted earlier it mentions you cant use a K24 tranny on this swap as there currently arent any mounts on the market for it (not sure how true this is).

I think they are talking about mounting a k24a tranny to whatever car they are using it for. Because at the top, the block choices are all k24a's, and then in the tranny section they say that the k24a tranny doesn't work with current mounts in the market. But I'm 100% sure you can bolt a k24a tranny to a k24a2 block.

[jimmeh]

just buy a k20a2 and stroke it to 2.2L
go ask toda.

[Paul1985]

I think they are talking about mounting a k24a tranny to whatever car they are using it for. Because at the top, the block choices are all k24a's, and then in the tranny section they say that the k24a tranny doesn't work with current mounts in the market. But I'm 100% sure you can bolt a k24a tranny to a k24a2 block.
Your right, what about all the people doing straight K24A2 swaps in EG/EK/DC. I doubt they are throwing on different tranny's all the time.

I remember reading a while back you need an OEM mount (i think CRV from memory) for the K24 swap into an EG.

[civlowwer]

So why int he world would you want to buy a k24 in the first place just to destroke it to 2.0 :thumbdwn: :thumbdwn: :thumbdwn:
well another great post do your research b4 you make your comment about the topic,

putting on a k20a head onto the k24a is how u get around drive by wire, also other pros and cons too, but try k20a.org great website

[civlowwer]

just buy a k20a2 and stroke it to 2.2L
go ask toda.


also try crower, crower offers a 2.35l stoker kit tooo

[sifoo]

well another great post do your research b4 you make your comment about the topic,

putting on a k20a head onto the k24a is how u get around drive by wire, also other pros and cons too, but try k20a.org great website

i know my shit - no need for you to tell me to research

I was just commenting on why he was wanting a 'destroked' motor when he couldve just bought a k20a in the first place... swapping heads does not destroke a motor ..

[Jums]

Lol ! ! !

[yourfather]

i know my shit - no need for you to tell me to research

I was just commenting on why he was wanting a 'destroked' motor when he couldve just bought a k20a in the first place... swapping heads does not destroke a motor ..
Very good point. I can see why he might want to run a K20A head.
But i think the removal of drive by wire would be the main benefit from the head swap.
The potential increase in power by swapping a head wouldn't be enough to justify the money being spent, but it would mean you could do other cool stuff to it like mentioned before, boosting etc.

I mean, I'm not a mechanic, I don't work on my car, but, I understand what you're saying pretty well.

And Jimmeh makes a good point of just buying the K20A firsthand.

[aaronng]

i know my shit - no need for you to tell me to research

I was just commenting on why he was wanting a 'destroked' motor when he couldve just bought a k20a in the first place... swapping heads does not destroke a motor ..
Because the k24a's deck height is taller than the k20a, so you can produce a k20a with an ideal R/S ratio using a suitable crank and longer rods.

[Paul1985]

Very good point. I can see why he might want to run a K20A head.
But i think the removal of drive by wire would be the main benefit from the head swap.
The potential increase in power by swapping a head wouldn't be enough to justify the money being spent, but it would mean you could do other cool stuff to it like mentioned before, boosting etc.

I mean, I'm not a mechanic, I don't work on my car, but, I understand what you're saying pretty well.

And Jimmeh makes a good point of just buying the K20A firsthand.
Its simple..
You get the Torque of the K24A aswell as the high revving top end power from the K20A. Just look at the results from such a swap :)

[yourfather]

So you think that 223 nm for a K24A compared to 192nm for a K20A2 is really work it. you're paying how much for a head for 20nm of torque?

[aaronng]

So you think that 223 nm for a K24A compared to 192nm for a K20A2 is really work it. you're paying how much for a head for 20nm of torque?
K20a's head on a k24a is not that worth it if you are just doing the swap for high end RPM torque. You might as well just swap in k20a cams. The thing is, when you start using aftermarket cams, you need an aftermarket ECU to tune. There is NO aftermarket ECU for the k24a2/3 except for the Motec (which is bloody expensive). That's why they use the k20a head.

BTW, with just a head swap, the k24a2's safe redline is still 7300rpm. Fuel cutoff is now the k20a's 8200rpm, but I don't think that the k24a2 can survive repeated RPM above 7500rpm. If you watch vids of people trying out the hondata reflash, the engine starts to sound weird at 7500rpm.

[yourfather]

Well, contrary to what you are saying, Paul1985 says that it's why you'd do it.

You'd get the torque of a K24 and the revs of a K20.... Seems pretty simplistic to me.

Why not just have a K20A and stroke it, like previously said. You've already got all the aftermarket support you need.

[HRD2BQT]

If you already have and existing K20A2 motor and have all the money to burn, the yeah - go the STROKER KIT way (expect to be $5-7G's poorer)

If starting from scratch - to buy a K20A2 half-cut, ur looking at paying around $6-7G's + all other expenses to do the swap - thats easy 10G's+ all up.

If you prefer it the hard way and want to save $$$. Go the K24/K20 Frank way. YOu gotta purchase all your parts separately and put them all together - TIME CONSUMING and takes a lot of patience. Just to giv u rough guage how much to do this:
K24 Bare Block - $800-1500
K20A2 Completed Head - $1000-2000
6 Speed LSD Box - $2000-2500
5 Speed Base DC5 - $800-1500
+ all the necessary parts (mounts, harness, ecu etc)
This can be done for the same price of a normal K20A2 swap - but you get more hp per $$$ and a more torquey motor that can be safely rev'd up to 8000 with the right piston / rod combo.

It all comes down as to how much you want to spend and how far you want to go and what u want to achieve.

Do you prefer Torque or HP? - never ending debate! hahahhahaha

For more infos about K series, go visit the ff:
www.k20a.org (http://www.k20a.org)
www.k-series.com (http://www.k-series.com)
www.clubrsx.com (http://www.clubrsx.com)

plenty of technical information awaits you :) :) :)

Eoh

[HRD2BQT]

Well, contrary to what you are saying, Paul1985 says that it's why you'd do it.

You'd get the torque of a K24 and the revs of a K20.... Seems pretty simplistic to me.

Why not just have a K20A and stroke it, like previously said. You've already got all the aftermarket support you need.

In addition to this, just bcoz u mate a K20A2 on a K24 block it doesn't necessarily mean you can rev safely as high as a normal K20A2 - this is not always the case specialy for a stock bottom end (not design for high RPM). You need to build the bottom end with Forged Piston & Lighweight Rod if u intend to rev up to 8000RPM+

[aaronng]

In addition to this, just bcoz u mate a K20A2 on a K24 block it doesn't necessarily mean you can rev safely as high as a normal K20A2 - this is not always the case specialy for a stock bottom end (not design for high RPM). You need to build the bottom end with Forged Piston & Lighweight Rod if u intend to rev up to 8000RPM+
True. If the builder is keeping the 99mm stroke, the bottom end still cannot withstand 8000rpm even with forged piston and lightweight rods. Even the SCCA TSX which has a built bottom end can only rev up to 7800rpm.

[Paul1985]

If you already have and existing K20A2 motor and have all the money to burn, the yeah - go the STROKER KIT way (expect to be $5-7G's poorer)

If starting from scratch - to buy a K20A2 half-cut, ur looking at paying around $6-7G's + all other expenses to do the swap - thats easy 10G's+ all up.

If you prefer it the hard way and want to save $$$. Go the K24/K20 Frank way. YOu gotta purchase all your parts separately and put them all together - TIME CONSUMING and takes a lot of patience. Just to giv u rough guage how much to do this:
K24 Bare Block - $800-1500
K20A2 Completed Head - $1000-2000
6 Speed LSD Box - $2000-2500
5 Speed Base DC5 - $800-1500
+ all the necessary parts (mounts, harness, ecu etc)
This can be done for the same price of a normal K20A2 swap - but you get more hp per $$$ and a more torquey motor that can be safely rev'd up to 8000 with the right piston / rod combo.

It all comes down as to how much you want to spend and how far you want to go and what u want to achieve.

Do you prefer Torque or HP? - never ending debate! hahahhahaha

For more infos about K series, go visit the ff:
www.k20a.org (http://www.k20a.org)
www.k-series.com (http://www.k-series.com)
www.clubrsx.com (http://www.clubrsx.com)

plenty of technical information awaits you :) :) :)

Eoh
Spot on.
+rep for you.

[barefootbonzai]

HRD2BQT - Probably the only guy in this thread to be acutally doin it, so probably a good idea for the e-mech's to listern to the man.

PS. didn't realise you where Eoh, still waiting for updates man. It's dang by the way.

[HRD2BQT]

Hey Dang, yeah it's me hahahahah......updates will be up hopefully in a week or so - just waiting for the rod to arrive then the build begins :)

thanks for d + rep guys.

[barefootbonzai]

Sweet sounds good. We just waiting on fuel lines and driveshafts, hopefully finish soon.

[jimmeh]

True. If the builder is keeping the 99mm stroke, the bottom end still cannot withstand 8000rpm even with forged piston and lightweight rods. Even the SCCA TSX which has a built bottom end can only rev up to 7800rpm.

im gonna disagree with you on that. i just bought a ordered a set of high comp pistons for a k24/k20 and the customer said dyno dave told him itll be safe to take her to 9000rpm

[Tony]

Hi, just want to correct a few things..

1/ You don't neccessary need to swap the K24 head to k20 to eliminate drive by wire, you can use a K20 intake manifold/TB and weld/plug the intake manifold coolant passage on the K24 head. If you are using a CRV K24 head, you don't even need to weld/plug the coolant passage. or you can simply get an adapter plate for K20A/A2 throttle bodies.

2/ K20A cams won't work on K24A1/A3/A4 engines unless you swap the rocker arm setup. The spring, spring seat and retainer size are different too.

3/ 99mm stroke can rev to 8000rpm all day long on properly built engines. There's no sign of premature wear on the rod bearings after 200 passes.

[aaronng]

3/ 99mm stroke can rev to 8000rpm all day long on properly built engines. There's no sign of premature wear on the rod bearings after 200 passes.
I am more concerned with the wear on the rings and liner. Not the bearings.

[Tony]

I am more concerned with the wear on the rings and liner. Not the bearings.

The rings (ductile iron plasma moly inlay top ring and premium iron taper faced rings) and stock K24 liner (bored to 87.5mm) are doing fine at 8000rpm, not sure how long it'll last though. We'll find out when I open the engine again next year.

[barefootbonzai]

Tony does that mean your car is up and running? What times you pulling?

[Tony]

Should see the track sometimes in September. Queensland raceway that is :P Not willowbank hehe

I'm using the PRB manifold until the IPS manifold arrives, should be able to get close to 280whp with the IPS intake manifold. I ordered that manifold back in August last year and it's still in production..

[spoondc2]

Should see the track sometimes in September. Queensland raceway that is :P Not willowbank hehe

I'm using the PRB manifold until the IPS manifold arrives, should be able to get close to 280whp with the IPS intake manifold. I ordered that manifold back in August last year and it's still in production..

Had been waiting for so long :p
Hope to see some real monster soon muhahahah

[Tony]

Had been waiting for so long :p
Hope to see some real monster soon muhahahah

I'm taking out the VTC system this week, going to replace the VTC stuff with adjustable gears so the cam angle is locked and no longer affected by oil pressure drop during high G corners. Hopefully I'll be able to make it to the next SAS.

[aaronng]

I'm taking out the VTC system this week, going to replace the VTC stuff with adjustable gears so the cam angle is locked and no longer affected by oil pressure drop during high G corners. Hopefully I'll be able to make it to the next SAS.
Post a video for me! I want to hear the k24a at 8000rpm in all it's glory! :thumbsup:

How much does the pressure drop by in high G corners? Did you go baffled sump as well? How much did that cost?

[spoondc2]

I'm taking out the VTC system this week, going to replace the VTC stuff with adjustable gears so the cam angle is locked and no longer affected by oil pressure drop during high G corners. Hopefully I'll be able to make it to the next SAS.

Waiting for you.... :thumbsup:
Add oil

[EG5]

some 99mm stroke can rev pass 10k rpm with the right combo of oil pumping system and rod/piston combo.

[HRD2BQT]

HRD2BQT - Probably the only guy in this thread to be acutally doin it, so probably a good idea for the e-mech's to listern to the man.

PS. didn't realise you where Eoh, still waiting for updates man. It's dang by the way.

I actually got few pointers from Tony - whom I bliv has built a solid k24/k20 frank. This guy know his k24/k20 more than me :)

[Chris_F]

can't wait to see your car running tony.. its been a long time in the works

[Paul1985]

i can tell this is going to be one of my fav cars in australia :D
i remember seeing your pics up when you were just starting it.

[barefootbonzai]

I actually got few pointers from Tony - whom I bliv has built a solid k24/k20 frank. This guy know his k24/k20 more than me :)

lol yer, but he wasn't in this thread when i made my comment :p

Tony - Hopefully i'll be out at QR in sept as well, can't wait to see your thing go.

[HRD2BQT]

Tony, what colour bearing did u use again?

Are the EURO K24A3 & CRV K24A1 bearings d same? Or they uses different ones according to the number listed on the block/girdle?

[Tony]

Tony, what colour bearing did u use again?

Are the EURO K24A3 & CRV K24A1 bearings d same? Or they uses different ones according to the number listed on the block/girdle?

Hey Eoh, I didn't know you are on OzHonda as well :p

Have a look at the code on the con-rod. If the code reads PPA then it should be the same as CRV.

I used all green bearings coz Honda didn't have black and brown bearings in stock. Just need to make sure the rod bearing to crank journal clearance is between 0.0013" - 0.0026" (install clearance limit). The difference between each colour is about 0.0001" to 0.0002". (Blue is thickist, then Black, Brown, Green, Yellow, Pink, Red is the thinnest)

[todaek9]

everyone is going for K series...what about B20???... :(

[Paul1985]

2.4l FTW :D

[HRD2BQT]

no replacement for displacement :) ahahhhhhaa

[Paul1985]

no replacement for displacement :) ahahhhhhaa
:thumbsup:
cant get much larger a displacement from a honda engine than this!

[VTi_b0i]

hey paul, r u putting a k24 in ur eg?

[Paul1985]

hey paul, r u putting a k24 in ur eg?
Maybe :p

[HRD2BQT]

DO IT!!! :)


Maybe :p