K20a3 Cams In A K24a1 Motor???? [Archive] - K-Series Forums

: K20a3 Cams In A K24a1 Motor????



mustclime
04-11-2006, 07:40 PM
Here is the deal, I am looking at dropping a k24a1 in my ep3. When I look at where the crv motor makes peak hp and peak tq it is very plain that it is camed for low tq number...Very good for a truck.....but a "hot hatch"?

Now the question: Has anyone on here ever run a crv mill with si cams?

thaduke2003
04-11-2006, 09:29 PM
You mean an A3 head I'm assuming- I know it's been done- I can't imagine you could put the cams into the CR-V head though. If you can, get the A2 heads- they'll get you the HP to match the 2.4L's torque- Mark W.

mustclime
04-11-2006, 10:36 PM
The k24a1 and the k20a3 have the same type of head. The crv head flows as well as a k20a2 though( just not the a2 vtec). If you look at the crv motor, It makes peak tq at 3600 rpm there the k20a3 makes peak tq at 5000rpm.......this is a result of the differance in the cams.....Big suprise, the crv is camed like a truck....

What I am looking for is if anyone has swapped out the crv cams with the cams out of a si.......The more I think about it, the more I think there is some big hp to be had there....

thaduke2003
04-12-2006, 09:58 AM
Hmm- I'd want to look at both of the heads side-by-side, but it could be doable- I say go for it, but have a plan B ready to rock- Mark W.

bc2k20a3
04-21-2006, 09:14 PM
a guy on ephatch put a3 cams in the k24a1 head. i think his name was k24si. he was from charlotte,nc and it was his girlfriends car.

civictype-s
05-15-2006, 12:48 AM
if you are worried about, just swap an si rocker arm set. they are cheap and probably pretty easy to find. it will bolt right up for sure but im pretty sure as long as you have k-pro, the cams should fit fine on the stock rocker arm set. just need to tune for it.

k-series
05-15-2006, 08:12 AM
I'm more curious as to why you'd want to do that instead of a full A2 head swap?

Steve

mustclime
05-15-2006, 08:20 AM
That is just it....I do not want to run k-pro, I want to run the ep3's ecu....

The more I understand kpro, the more I understand I do not want it on my car.

mustclime
05-15-2006, 08:56 AM
I'm more curious as to why you'd want to do that instead of a full A2 head swap?

Steve
The real question is why do you have to do a a2 head swap on a k24a1?
A k24a1 head flows as well as a k20a2 head( see hondadatas web sight) and you have no bissness reving a k24a1 like a type-s mill in the first place.....
With the added stroke of a k24, the piston speed of a k24 at 7500rpm is the same as a s2k mill at 9000rpm!.....Have you seen what the s2k's rods look like? How about the k24a1 rods?......:(
The ivtec of the k20a and a2 is great if you motor can rev like a 2 stroke. The k24a1 is a truck motor with a very good flowing head and a very long set of intake runners( for low end tq). To me It makes more sence to look at bolting on a si intake manifold and a set of cams than a type-s head.

I was just wondering if anyone had done it....

mustclime
05-15-2006, 09:00 AM
a guy on ephatch put a3 cams in the k24a1 head. i think his name was k24si. he was from charlotte,nc and it was his girlfriends car.
Nope, he never got around to it before they broke up.....Said he spent like $6000 grand on her car before they split up.......kinda sucks a little....:(

civictype-s
05-15-2006, 10:58 PM
The real question is why do you have to do a a2 head swap on a k24a1?
A k24a1 head flows as well as a k20a2 head( see hondadatas web sight) and you have no bissness reving a k24a1 like a type-s mill in the first place.....
With the added stroke of a k24, the piston speed of a k24 at 7500rpm is the same as a s2k mill at 9000rpm!.....Have you seen what the s2k's rods look like? How about the k24a1 rods?......:(
The ivtec of the k20a and a2 is great if you motor can rev like a 2 stroke. The k24a1 is a truck motor with a very good flowing head and a very long set of intake runners( for low end tq). To me It makes more sence to look at bolting on a si intake manifold and a set of cams than a type-s head.

I was just wondering if anyone had done it....

the reason to do an a2 head would be for more aggressive exhaust cam lobes. you basically lose the v-tec on the exhaust side on an a3 or a1 head. the head CAN flow equally as well but you are not getting full potential of it since the exhaust side is pretty limitted.

you are missing the main reason to not doing an a2 head swap. you are correct in that you need to rev it higher to take full advantage of the a2 head but not because of flow, its because the a2 motor is designed with more compression in mind and a high peak torque rpm for the v-tec crossover. if the a2 motor v-tec is normally set at 5300 or whatever and you only rev to 7500rpm, you are going to drop out of v-tec in between shifts. then if you try to lower the v-tec your power band becomes spikey.

in short, unless you are upgrading your bottom end to rev to 8800 like i do, an a2 head swap is not completely beneficial. i say if you have the parts, just do the a3 cams. couldnt hurt, but if you are going to be spending money, spend it on the bottom end. an k24 is nice but isnt super effective unless you can rev the piss out of it.

mustclime
05-16-2006, 09:05 AM
the reason to do an a2 head would be for more aggressive exhaust cam lobes. you basically lose the v-tec on the exhaust side on an a3 or a1 head. the head CAN flow equally as well but you are not getting full potential of it since the exhaust side is pretty limitted.

you are missing the main reason to not doing an a2 head swap. you are correct in that you need to rev it higher to take full advantage of the a2 head but not because of flow, its because the a2 motor is designed with more compression in mind and a high peak torque rpm for the v-tec crossover. if the a2 motor v-tec is normally set at 5300 or whatever and you only rev to 7500rpm, you are going to drop out of v-tec in between shifts. then if you try to lower the v-tec your power band becomes spikey.

in short, unless you are upgrading your bottom end to rev to 8800 like i do, an a2 head swap is not completely beneficial. i say if you have the parts, just do the a3 cams. couldnt hurt, but if you are going to be spending money, spend it on the bottom end. an k24 is nice but isnt super effective unless you can rev the piss out of it.
Dude, you are all over the place.......no,kinda ,yes?????? That is how I read your reply...:confused:

What is the point of biulding a k24a1 bottom end? All you would keep is is the block.....the crank is not balanced, the rods are wimpy, the pistons are low compression, the oil pump has that balance shaft thing going on....:(

I am just looking for cheap hp, my k20a3 is not cutting it...You can pick up a good k24a1 for $1300 or less......as the start of the thread states, I was just looking to see if anyone tossed a set of k20a3 cams in a k24a1 motor yet....

k-series
05-16-2006, 09:17 AM
It's gotten a little off topic, but the conversation is good.

Does anyone have a comparo of A1 vs A3 cams?

Steve

thaduke2003
05-16-2006, 10:56 AM
By the way, civictypes, part of the reason the A2 head makes power more at high RPM's IS because of how well it flows- bigger CFM #'s (higher/better flow)= more power up top, less down low- Mark W.

civictype-s
05-16-2006, 10:33 PM
Dude, you are all over the place.......no,kinda ,yes?????? That is how I read your reply...:confused:

What is the point of biulding a k24a1 bottom end? All you would keep is is the block.....the crank is not balanced, the rods are wimpy, the pistons are low compression, the oil pump has that balance shaft thing going on....:(

I am just looking for cheap hp, my k20a3 is not cutting it...You can pick up a good k24a1 for $1300 or less......as the start of the thread states, I was just looking to see if anyone tossed a set of k20a3 cams in a k24a1 motor yet....

dude im trying to help you in justifying to everyone else that doing an a2 head swap is not cost effective with a stock k24 block. and if you are looking for more HP with a k24 than your k20a3 you are looking in the worng place with the stock a1 or a3 cams. you will gain torque, but hp will not be increased. sorry for trying to help.

PapiTuyo326
05-17-2006, 03:28 AM
If you dont want to run kpro, how do you expect to tune for the si's cams on the k24. Are you goign to simply use the Eps ecu? I think you need to accept that some sort of engine management is needed. If you dont like kpro, go with AEM ems. You will not get good results by half assing a cammed setup by lacking proper engine management.

My advice: Get kpro and skunk2's new non vtec k-series cams. With some nice tuning and supporting n/a mods, youll be able to make over 210 whp and FAT tq. Ive had some info on skunk's non vtec cams for a while. Theyve made 250whp on a stock bottom end k24a1 and only revved it to 7200rpm. ;)

Oh, and you know who to go for them K24s ;)

k-series
05-17-2006, 08:27 AM
sorry for trying to help.

I don't think he really read your response. Figured you were jumping on him about getting an A2 head like everyone else.

Thanks for helping though, seriously.


Steve

k-series
05-17-2006, 08:28 AM
Oh, and you know who to go for them K24s ;)

Man, I wish I could fit one in my DA..../sigh.

:(


Steve

mustclime
05-17-2006, 09:47 AM
If you dont want to run kpro, how do you expect to tune for the si's cams on the k24. Are you goign to simply use the Eps ecu? I think you need to accept that some sort of engine management is needed. If you dont like kpro, go with AEM ems. You will not get good results by half assing a cammed setup by lacking proper engine management.

Here is where my plans are leaning.....I have a 03 ep3 with a k20a3 motor in it. I am looking some more cheap hp, I already have all the boltons, h/i/e. In the old days, if you wanted more hp, you got a bigger motor.....that is why I am looking at the k24a1's....
Now, what is the differance between a k24a1 and a k20a3? From my research I have come up with intake maifold, exost manifold, 400cc's, ecu's and cams( block and rods are part of the 400cc's) .....I was very suprised to find out the injectors,sparkplugs and coilpacks are the same in both motors.......
There have been several people on the forums that have run the k24a1 motors with the k20a3 ecu's but they have not run the a3 cams....that is why I have started the thread.....
The next question to ask is would cams change the the timing of the motors......yes..... To me it just makes sence to change the cams...
As for kpro.......I think they are a step backward in motor cotrole for the average user. If the weather changes, the kpro tune is toast. I live in nj, temps go from sub zero to over 100.....To run kpro right, you have to have like 3 tunes!!??? A winter tune, a a spring/fall tune and summer tune....:angry: When you convert a ecu to kpro, you distroy the "thinking" part of the ecu. You distroy the part of the ecu that adjusts for weather, plug wear, fuel content, mixture...ect.:(

k-series
05-17-2006, 10:11 AM
Maybe you should consider running Guardian from Cybernation then.


Steve

mustclime
05-17-2006, 10:21 AM
dude im trying to help you in justifying to everyone else that doing an a2 head swap is not cost effective with a stock k24 block. and if you are looking for more HP with a k24 than your k20a3 you are looking in the worng place with the stock a1 or a3 cams. you will gain torque, but hp will not be increased. sorry for trying to help.
Its cool man....I am sorry I came across as a ass hat......


Have you looked at where the the crv motor make peak tq? Peak tq for the crv is made a 3600rpm while the ep3 motor makes peak tq at 5000rpm.
Both motors make 160hp while the crv motor has 1/8th more displacement. From my understanding of motors, cams play a large part in where a motor make peak hp and peak tq.

It does not make sence to me.......

nighthawk
07-03-2006, 09:43 AM
from what i've read the cams are the same between the k20a3 and k24a1 and k24a4.

The lower peak power comes from the same sized cams in a larger displacement motor.

mustclime
07-03-2006, 09:53 AM
from what i've read the cams are the same between the k20a3 and k24a1 and k24a4.

The lower peak power comes from the same sized cams in a larger displacement motor.
The cams are swapable, but they are not the same......look at where they make peak tq and peak hp. Crv cams are tuned to make tq low in the rpm range where the si cams make the peak tq numbers at 5000 rpm.....

thaduke2003
07-03-2006, 11:21 AM
Where they make power is also a function of combustion chamber shaping, head flow, port sizing, etc.- not all about the bumpsticks- Mark W.

03DSM-RSX
08-21-2006, 05:37 PM
That is just it....I do not want to run k-pro, I want to run the ep3's ecu....

The more I understand kpro, the more I understand I do not want it on my car.

then you shouldnt even be modding. Kpro is where you can make peak gains out of anything u have.

mustclime
08-23-2006, 01:30 PM
then you shouldnt even be modding. Kpro is where you can make peak gains out of anything u have.
K pro = at least $1500 bucks......that is more than the price of the motor.......


Fyi......k pro =900+ you have to pay someone to tune it.....that is where the 1500 number comes from.

03DSM-RSX
08-24-2006, 11:03 AM
so? why cheap out something crucial and have it running at minimal performance? why do it at all? the stock ecu isnt going to readjust it for you.

u gota pay to play.

mustclime
08-24-2006, 08:03 PM
so? why cheap out something crucial and have it running at minimal performance? why do it at all? the stock ecu isnt going to readjust it for you.

u gota pay to play.
Not everyone is sponcered by mom and dad......

k-series
08-24-2006, 08:29 PM
Not everyone is sponcered by mom and dad......

Neither am I and I'm getting K-Pro. I'm gonna have to say you're wrong on this one and K-Pro is the only way to run this combo.

Steve

khoalie
09-27-2006, 01:44 AM
i'm going to go against the grain here and say that kpro, although it would yield the best results, in this application isnt necessary to have a solid running and reliable motor. since the a3 ecu has timing maps designed to run on low octane fuel, and the k24a1 motor is also designed to run on a low octane fuel, using the stock timing maps will be sufficient and will not harm the motor, ie cause knock, if you step up to premium fuel.

now given that the k24 will require more fuel simply because it will draw in more air, you can use a simple piggyback to add it. whether it be emanage or even an afc, if you leave vtec engagement alone and only use it to manipulate the map sensor reading thereby adjusting fuel, it will run fine and not throw any codes. simply put it on a wideband and just tune off the a/f reading.

is it ideal? no. is it cheap? yes. is it effective? yes. will it degrade the reliability of the motor? most likely not

mustclime
09-27-2006, 04:02 PM
Wow...back from the dead......I have someone running this combo with type-s injectors(310cc vs 270cc) in a eg....Tring to get him to dino it...the thing way fast....