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Discussion Starter #1
There seems to be a lot of mis-information regarding the new K series head we had on display at SEMA (http://www.k20a.org/forum/showthread.php?t=51288).

http://www.gbrtuning.com/K-ChamberExh1.jpg

First, the retail price of the bare head will be $550.00 (or less). This head isn't as complex as the B series, so if we can do the final version for less, we'll pass the price on to the customer.
The first two castings were based on the K24 TSX head that we've gained so much experience with this last year. There are many obvious port improvements that have netted roughly a 40cfm improvement in airflow on both intake and exhaust-sides of the head.
I've also made the head's deck thickness 2.0mm thicker than the factory head (with the increase being inside the water jacket). This should allow users to run much higher cylinder pressure without head gasket failure.
The intake valve seat insert is also large enough to permit machining for a full 36.0mm valve with material to spare for good seat stability. Production valve guides will be the manganese/bronze "aero-guides" we use in all the race heads we prepare here.
The port walls are thick enough to permit porting beyond the size we currently use at 398cfm.
Changes I'm making right now include a multi-flange intake face which will allow the use of RSX, Civic Si, and TSX intake and water manifolding. I'm also placing a water outlet on the exhaust-side for applications needing it. Plugs will be included for those who don't. There will also be a plate that blocks-off the EGR manifolding at the end of the head. The plate will incorporate the appropriate bolt holes for those specific applications.
In order to "do" the head, I've have to make the head work on as many applications as possible, thus keeping the stock porting at a level where it doesn't "kill" torque when used on a stock 2-liter engine. We currently have three programs for CNC porting of these (and Honda castings) for various performance levels, so we'll be offering a number of port styles as an option along with intake seats that will accept up to 38mm valves in both powdered steel and beryllium/copper (for those running titanium valves). Core plugs in the head will also be thread-in rather than press-in for additional integrity.
On the exhaust-side, several individuals requested that we fill-in the weight-saving voids between the exhaust ports to permit straight-line porting without welding, and that's an easy change I'm also making right now.
At SEMA, I requested that all of those who are interested contact me with any other changes they'd like to see.
From a scheduling standpoint, I've been told that we'll have final castings within 90 days after I submit the final design.
That pretty much sums it up. I'd also like to say that I really enjoyed the opportunity to talk with a number of you, and I'm excited at the opportunity to make this head a reality....especially in these times when money is so tight.
Larry
 

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Would there be alot of hassle in adding an additional boss for a aftermarket temp sender in the waterjacket similar to the OEM boss?
 

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Discussion Starter #7
I'll look around ad see if we can add a boss for another temp sensor. On the B series heads, we receive 150 at a time, so they will be in stock.
Once we've recovered a bit from the investment, we'll also do another version with more expansive porting (as cast), along with our ProStock high compression combustion chamber (like our S2K Pro heads).
 

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There seems to be a lot of mis-information regarding the new K series head we had on display at SEMA (http://www.k20a.org/forum/showthread.php?t=51288).

http://www.gbrtuning.com/K-ChamberExh1.jpg

The first two castings were based on the K24 TSX head that we've gained so much experience with this last year. There are many obvious port improvements that have netted roughly a 40cfm improvement in airflow on both intake and exhaust-sides of the head.

A 04-05 TSX head or a 06-08 TSX head?

So the newly designed head casting gained 40cfm more on the intake/exhaust side over the 04-05 TSX head?
 

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very nice...
 

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Discussion Starter #15
The head is based on the '06 and later heads, which come from the factory with 36mm intakes, but anyone who's familiar with those heads knows that the seat insert (from Honda) is only machined for a 35mm valve, putting the seat .020" inborad from the edge of the valve. The stock seat insert is also only large enough to permit machining a 35.5mm (race-style) valve seat configuration, and at that size, there's very little insert left in the head for stability. I designed our head with a seat insert that's large enough to accomodate a full 36.0mm race-style valve job with some left over for stability.
The exhaust seat consists of a radius sweep into the chamber, a 45° seat angle, and two radiuses below it which blend into the port bowl.
The intake seat is configured in much the same manner, so they're much more complex than simple valve jobs with discrete angles.
 

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The head is based on the '06 and later heads, which come from the factory with 36mm intakes, but anyone who's familiar with those heads knows that the seat insert (from Honda) is only machined for a 35mm valve, putting the seat .020" inborad from the edge of the valve. The stock seat insert is also only large enough to permit machining a 35.5mm (race-style) valve seat configuration, and at that size, there's very little insert left in the head for stability. I designed our head with a seat insert that's large enough to accomodate a full 36.0mm race-style valve job with some left over for stability.
The exhaust seat consists of a radius sweep into the chamber, a 45° seat angle, and two radiuses below it which blend into the port bowl.
The intake seat is configured in much the same manner, so they're much more complex than simple valve jobs with discrete angles.

Can you elaborate on your 40cfm increase, statement?
 

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Discussion Starter #19
Flow chart comparison with a stock TSX head:
http://www.gbrtuning.com/K-

#1 and #3 arwe stock TSX (36mm) intake and (30mm) exhaust respectively.
#2 and #4 are the untouched new head with 35mm intake and 30mm exhaust.

The price will be $550.00 (or less) for the bare head with guides and valve job.
As for elaborating on the ports...the short-turn's (both intake and exhaust) are much kinder than the OE head. They're also wider in flow-sensitive areas, and the port dividers are also somewhat thinner than stock. Remember, however, that it was mandated from the get-go that this head would perform well on a 2-liter, so port velocity had to remain high for torque.
If you look at the flow chart, you'll see that I also made as much flow improvement as possible for valve lifts at .500" or less, so making the heads work with relatively stock cams was also a necessity.

LW
 
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