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Hi guys.

My name is Dan and I'm an intern for Palm Beach Hot Rods. We have a customer with a 2004 Element who wants to push as much power (300 hp, either to the wheel or crank) as possible. Now were going to run all Skunk 2 internals and IM but were a bit confused on the head. Skunk 2 says to run the K24A2 head while I keep thinking to myself that the K20A2 head would be better. I only figured this because I do myself lurk around here and wish I had a K swapped DC2. I'm a Honda guy, and I love my TSX lol. Back to the issue at hand. Which is the better head to go with? It's challenging enough to try and get some form of a ECU (Auto for those who were thinking K Pro) but the head is killing us here. I wanna post on places and try to find one but I need to know which is the better one. If any of you members can help us out that would be fantastic. I will admit, it's our first K engine that were really digging into. And being that this is an Element who wants uber power (turbo perhaps in the future) were really going into uncharted waters but were loving every second of finding this info out. relies and PMs are welcome

Thanks!!!



And yes I searched, I'm a mod on TSXclub.com so I know how it goes lol
 

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The element in stock form has the k24a4 head. The tsx head has good midrange but at high RPM, the k20a2 flows more.

On an all motor setup, a 2004-2005 TSX head in stock form will not make as much power up high as a k20a2 head assuming decent cams etc.

A 2006-2007 TSX head will probaby make more power than a stock k20a2 head.

If you are planning to eventually go turbo, and you have the tSX head available, dont worry about getting the a2 head unless you have your choice and they are both available.

In all motor and with both heads being stock, the k20a2 flow better up high. We have posted a few graphs comparing the 2.

In turbo, it is not going to make a big difference with both stock heads.

So if you want to keep things simple, start with the motor stock.. People have made around 550whp out of a stock element motor with upgraded clutch of course etc...
 

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Thanks Nikos.

The head is also going to be ported and polished if my memory is correct. So then at that point would it become irrelevent what head I get. Even if I use the stock one?

As far as the head is concered with the interals of it, were stripping everything down and adding Skunk 2 components into it. Granted we know engines pretty well but like I said, it's our first real entry into the K series genre.
 

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Just wanted to ask a similar question what is better considering you have all at your disposal. A k20a2 head or a k20a type r head with a k24a2 ?

PLanning to upgrade my k24a2 so asking this question. Also would i be able to change the cams etc with the k20a head and all ?
 

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The typeR and the typeS head are the same exact casting, same part# for a bare head, there is absolutely no differences other than the valvesprings and cams.

The TSX head can be ported to flow slightly more than a stock A2 head, but the A2 head can be ported for even greater flow.
 

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The typeR and the typeS head are the same exact casting, same part# for a bare head, there is absolutely no differences other than the valvesprings and cams.

The TSX head can be ported to flow slightly more than a stock A2 head, but the A2 head can be ported for even greater flow.
when you refer to type S head compared with the Type R. you ar talking about the A2 right?

whats the diference compared with a Z1 and Z3? Z1 & Z3 same casting? better flow than A2?
 

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So technically waht would you prefer a k20a2 (type S head) or a k20a head or it doesnt make a difference what you use.

And if there is no difference then why is the difference of power between the two ? is it becuase of the cams inside the k20a ?
 

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It's splitting hairs to be honest. I have Frank'ed TSX block with a PRB head and a local friend has a full TSX motor. We make almost identical power. It's in the cams and valvetrain, not the head. There has not been any compelling evidence that I've seen to give one the nod over the other so I would just do whatever is easiest.
 

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keep in mind that the 2.0 L have a 50* VTC gear while the 2.4 L only have a 25* one.
Ive seen this so much but what does that really mean??? how and what is this 50* and 25* VTC gear mean. how does it make a diif. sorry im still new to k's

But to OP, i have a question are you doing ne thimng to the bottom end of the motor??? Because by swapping heads to a True VTEC head you gotta swap the pistons, they only reason i bring that up is because like nikos said the a2 flows better up tob because its build to go high RPM but the k24's are all made for torque so they arent made for highRPM. BUT if you are changing the pistons and rods than it would be best to go with a2 for power up top at higher RPM and that bootem end torque
 

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Ive seen this so much but what does that really mean??? how and what is this 50* and 25* VTC gear mean. how does it make a diif. sorry im still new to k's

But to OP, i have a question are you doing ne thimng to the bottom end of the motor??? Because by swapping heads to a True VTEC head you gotta swap the pistons, they only reason i bring that up is because like nikos said the a2 flows better up tob because its build to go high RPM but the k24's are all made for torque so they arent made for highRPM. BUT if you are changing the pistons and rods than it would be best to go with a2 for power up top at higher RPM and that bootem end torque
What exactly are you trying to do? The answer will depend on that.
 

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Ive seen this so much but what does that really mean??? how and what is this 50* and 25* VTC gear mean. how does it make a diif. sorry im still new to k's
Honda's VTC gears continuously vary the intake camshaft angle throughout the rpm range. This allows you to optimize the intake cam angle to make the most power throughout the whole rpm range.

The VTC value (ie 25 vs 50) is not the angle of the camshaft itself, but from my understanding it's more of a measurement in overlap between the intake and exhaust cam angle.

The 2.0L's have the ability to create more overlap than the 2.4 L's (25 degrees more), so by using a 50 degree VTC on a 2.4 L motor, you can increase the powerband throughout the whole rpm range. 50 degrees is probably not safe on a 2.4 L due to the possibility of valve to valve contact, and in order to figure out what the max SAFE vtc gear angle would be, you need to clay the motor.
 

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Honda's VTC gears continuously vary the intake camshaft angle throughout the rpm range. This allows you to optimize the intake cam angle to make the most power throughout the whole rpm range.

The VTC value (ie 25 vs 50) is not the angle of the camshaft itself, but from my understanding it's more of a measurement in overlap between the intake and exhaust cam angle.

The 2.0L's have the ability to create more overlap than the 2.4 L's (25 degrees more), so by using a 50 degree VTC on a 2.4 L motor, you can increase the powerband throughout the whole rpm range. 50 degrees is probably not safe on a 2.4 L due to the possibility of valve to valve contact, and in order to figure out what the max SAFE vtc gear angle would be, you need to clay the motor.
So its a timing thing then right???!!! just tryin to edumucate myself a little more
 

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Honda's VTC gears continuously vary the intake camshaft angle throughout the rpm range. This allows you to optimize the intake cam angle to make the most power throughout the whole rpm range.

The VTC value (ie 25 vs 50) is not the angle of the camshaft itself, but from my understanding it's more of a measurement in overlap between the intake and exhaust cam angle.

The 2.0L's have the ability to create more overlap than the 2.4 L's (25 degrees more), so by using a 50 degree VTC on a 2.4 L motor, you can increase the powerband throughout the whole rpm range. 50 degrees is probably not safe on a 2.4 L due to the possibility of valve to valve contact, and in order to figure out what the max SAFE vtc gear angle would be, you need to clay the motor.
But Whats failing to be mentioned is that You can actually Machine the TSXK24A2 VTC mech to 45 or even 50
So its a timing thing then right???!!! just tryin to edumucate myself a little more
Yes partially. VTC provides more cam angle adjustability
 

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So, if we port and polish the k24a2 cylinder head for better airflow as well as machine the vtc on the k24a2 to 50 degrees, would we has almost 2 identically functioning heads or is there some other benefit to having the k20a2 head over the 24a2 head? I am trying to learn as well as save money. Plans also include building up the head.
 

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Speak to Luke at 4 Piston Racing, he'll set you straight with which head to go for based on application and sort you out with one if needed.
 

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Honda's VTC gears continuously vary the intake camshaft angle throughout the rpm range. This allows you to optimize the intake cam angle to make the most power throughout the whole rpm range.

The VTC value (ie 25 vs 50) is not the angle of the camshaft itself, but from my understanding it's more of a measurement in overlap between the intake and exhaust cam angle.

The 2.0L's have the ability to create more overlap than the 2.4 L's (25 degrees more), so by using a 50 degree VTC on a 2.4 L motor, you can increase the powerband throughout the whole rpm range. 50 degrees is probably not safe on a 2.4 L due to the possibility of valve to valve contact, and in order to figure out what the max SAFE vtc gear angle would be, you need to clay the motor.
If you're going for 300hp all motor you'll need higher compression pistons and the 50 degree VTC. The fortunate thing is if you're going with something like Wiseco 12.5:1 pistons, they have super deep valve reliefs so you don't need to worry about Valve-to-piston contact unless you get super aggressive cams.
 

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Thanks for the replies but my question was more related to if there would still be a difference between the K24a2 and K20a2 head if the K24a2 head was ported for more flow and the VTC gear upgraded to the 50*. Thanks sorry if i was not more clear.
 
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