ZX-14 Heads/Ports

[DarkFalcon]

Anyone looked at these heads and want to comment or share observations?

[mountainmotor]

Well ,   the cross section on the inlet side is rather large looking and I could not help but notice the somewhat raised exhaust port floor and definatley the height of the exhaust roof  . The outer walls that are looking somewhat shrouded by eye from the throttle body /intake boot area seems just a result of building a compact design so an oval manifold boss was used --so it seems to me at least .

Revolutionary in design ? Not to me but I am not an enginneer . Suzuki should'could have bumped the compession and added some camshaft back in 2003 or so then the ZX-14 would have hit the world with a much larger .... thud    ZX owners please don't take offense , just funning around .

Anyway , the intake has Cosworth written all over it . This twin cylinder head is of Cosworth design from way back .



ZX-14 inlet



ZX-14 exhaust side

[Steve S]

Mountain, good eye. We have also looked at the head in some detail and the hybrid ports have a different approach than the Busa and tend to be more "straight" than "high". The divider is also closer to the port entry. The exhaust is like a pipe with a 90* on it.

[gazza414]

MM can you post some pics of the ZX14 which are a little larger ..thx

[mike46]

Mountain, good eye. We have also looked at the head in some detail and the hybrid ports have a different approach than the Busa and tend to be more "straight" than "high". The divider is also closer to the port entry. The exhaust is like a pipe with a 90* on it.

That 14 intake port looks very similiar to a 2000 ZX-9 port though the 9 divider is probably a bit longer. The 9 port has the longest divider I've seen

[busa416]

Spaz ported a 14 head and reassembled with all stock parts it made over 200 at the wheel.There is a post on psyhcobike about it.

[busa200]

what other mods were done?

[Steve S]

We..........Quantum Motorsports............picked-up 10 HP and made 205 HP STD. The package includes surfacing the head, degreeing stock cams, setting squish to a specific clearance and porting the head. A BDE pipe and PC are also required. For additional details call Bryan at 937-298-6204.

[DarkFalcon]

Based upon studies that have been shared with me, the 14 head flows 12 to 14 less CFM @ .400" @ 28" than the Busa head. I think they have gone out of their way to improve mixture motion and quality.........even at the expense of high lift flow. This, along with straight approach more than likely explains the longer duration camshaft. While not a porter, I don't see any home run opportunities on the intake side......I see singles like modifying the divider, removing pits, opening up the throats and working the bowl. Depending upon the application, I would be reluctant to fool around the minimum port sectional area because as Mountain noted these are already more than ample. Do others have ideas?

[gazza414]

DF, can you post side by side in stock configuration ( Busa vs ZX14 ) what you would consider reliable flow bench numbers ( at 0 to 350thou in 50 thou incrememts )

Just wanting to add some perspective to this.
thx

[HPINXS]

DF ,I believe you are correct .High straight ports produce tumble motion over lower ports that promote swirl.High ports will have less mass airflow at peak valve lifts,hence the need to increase cam lobe duration to produce high rpm power. The ZX family of engines has always seemed to be loosely based on early Cosworth DFV engine design.
I have never had a ZX-14 head in my possession to measure, Is the large cross sectional area you are referring to before the port divider or right before the short turn choke?If it is before the divider they were likely trying to create a reservoir or mini plenum if you like to drop the velocity before the air had to move into the secondary ports.The reason behind this is air is "dumb" so to speak it doesn't want to have to make a choice which port to goto. Also by dropping the velocity there it gives the air a chance to start flowing into the ports in a much more organized fashion.The long port dividers are there to promote inertia ram effect at the tail end of the intake event,which was most likely needed to help out torque production prior to peak torque as the inlet duration was increased.I would also believe the exhaust port design is along those lines also,as it being described as 90 degree elbow.

[HPINXS]

Mountain Motor the question about the cross section was meant to directed towards you,sorry if seemed like i was asking DF.I just got way ahead of myself typing

[Competition CNC]

I like this board.  I see some thinkers here.

Sorry to interrupt..... go on.

[osti33]

I like this board.  I see some thinkers here.

Sorry to interrupt..... go on.

Good to see you posting here Jim. Quite the smart bunch over here for sure.

[Competition CNC]

I've just finished making 3 very different digital Busa intake ports in MasterCam surface models.  The topic of cross sectional area is interesting because Suzuki engineers had a set of requirements they had to work with to make the bike a good street bike.  They needed to take into account things that some people dont care about.  Theres compromises in both the intake and even more so, in the exhaust port.  I'll post a few graphics shortly of the ports.
Nitrous guys can really bennifit from a good exhaust port.  After cutting up a busa head into carefully located slices its aparent that suzuki left plenty of casting thickness for changing port design on both the intake and exhaust.
This is not so important for our street head where you dont change the choke or bowls much, but its hugely important for the "big port" design for the big displacement engines.
The actual port velocity numbers on the flow bench at 28" are arbatrairy but do show accurate velocity trends at each cross sectional area.  After modeling a completely stock set of ports and analizing them and the cross sectional area every .100" down the port you can see how carefully the Suzuki engineers controlled cross sectional area.
Air speed increases 28% at the choke.  While this makes for nice torque boost just before the single cylinder induction frequency, it costs torque near the engine induction frequency.  I suspect that this is why suzuki put the flapper door in the air box, but I havent modeled the airbox to determine the resonant frequency change from the flapper door.  So thats just an assumption at this point.
The exhaust port is interesting that they use a "belly" port design and that some of the latest Nextel Cup exhaust ports are going to the belly port.  The only drawback to Suzukis version of the belly port is that they have EPA requirements
and needed to keep over scavenging to a minimum.   So this may explain the small cam specs on the exhaust side.
So with a cam spec change on the exhasut side and a general reduction in exhaust port velocity while increasing the flow rate, the nitrous guys and turbo guys can bennifit huge.

I'll be modeling and diving into a zx14 head this fall, it will be interesting to see how it will compare to the zx12r and Busa ports.

[DarkFalcon]

The actual port velocity numbers on the flow bench at 28" are arbatrairy but do show accurate velocity trends at each cross sectional area.  After modeling a completely stock set of ports and analizing them and the cross sectional area every .100" down the port you can see how carefully the Suzuki engineers controlled cross sectional area.
Air speed increases 28% at the choke.  While this makes for nice torque boost just before the single cylinder induction frequency, it costs torque near the engine induction frequency.

You guys are doing some interesting things. Why do refer to the flow velocities at 28" as being arbitrary and, secondly, which wave model do you think Suzuki is using for induction tuning?

[whtrthanu]

kawi has been using smaller ports for awhile, from what I have tested they are using higher velocities rather than adding port volume.....THe zx10 head is about 10ccs smaller than a 1000 ,and the same is true for the 14 and the busa......I guess its the old saying.........THeres more than one way to skin a cat............
Airflow = power no matter how you get it.....

[Competition CNC]

You guys are doing some interesting things. Why do refer to the flow velocities at 28" as being arbitrary and, secondly, which wave model do you think Suzuki is using for induction tuning?

Well the velocity calcs at 28" arnt what the port actually sees under running conditions. So the number is for reference and can show trending.   I'm sure Suzuki is using Optimum's software for designing these engines. GM, ford, mopar, motoGPteams, cup teams,prostock, F1 teams, just about everyone uses Virtual 4-stroke and automated Design from Optimum.  Theres nothing else like it. Nothing else is even remotely close in accuracy and complexity.  Its $36,000 for a one year licence.

Heres a MasterCam X2 screen shot of our Hayabusa stage 1 (street/drag up to 1440 cc) intake port with a stage 2 (turbo/nitrous) exhaust port.



And a screen shot of one of the cross sectional area calcs for the stage 1 intake port.



And a screen shot from Optimums V-4S software of pressure wave travel thru an engines ports. (not hayabusa)



And another screen shot from Optimums V-4S software of a velocity map thru a model. (not hayabusa)



Check out the web site.... http://www.optimum-power.com/default.htm

[DarkFalcon]

Well the velocity calcs at 28" arnt what the port actually sees under running conditions. So the number is for reference and can show trending.   I'm sure Suzuki is using Optimum's software for designing these engines. GM, ford, mopar, motoGPteams, cup teams,prostock, F1 teams, just about everyone uses Virtual 4-stroke and automated Design from Optimum.  Theres nothing else like it. Nothing else is even remotely close in accuracy and complexity.  Its $36,000 for a one year licence.

You are absolutley correct that in saying that the engine "sees" higher operating port speeds under running conditions than would be seen at testing a head at 28". However, 28" is a useful testing depression because it is equivalent....approximately.... to one atmosphere of pressure and yields steady state speeds approximately half of what would be found in an operating engine. The maximum speed attainable at 28" is around 350 ft/sec which, at that depression, is equivalent to Mach .6 so if you wanted port speeds to be .5 Mach you would design the port to achieve speeds around 292 ft/sec. Additionally, there a number of SAE papers and test databases that draw upon testing at 28" which has become an aftermarket, academic and SAE standard. Apparently not OEM.

Ford Dearborn USA measure to 3 different pressure drops.
10 inches of water, 20 inches of water and 5 inches of Mercury or about 68 inches of water.

I've worked with/for a few OEMs and none I know work with 28 inches of water. It must be the after market.

Most of the larger shops also use a pitot tube to calculate and measure local velocities within a sectional area. The next step up in the design process would be to use Virtual, Wave or Mandy.........and I thought Ford used both Mandy and Wave?

[Competition CNC]

We also use probes and manometers for velocity testing and "dead spots" among a few other things.   But these intake ports arnt your typical automotive port, they dont have any dead spots per say.  They do have areas of slightly lower velocity thou.  But on ports like this velocity averages are fine to work with.  The velocity varyations are so small in the port.

If your a member of SAE and you like induction tuning you should read paper 952138, 2001-01-3564 and 2004-01-0998 among others.  Even better get a copy of Blairs book.

[whtrthanu]

has anyone put one on a wet bench............

[Competition CNC]

We havent,....

[whtrthanu]

I was curious to see the effect of fuel pressure and puddling in the lower velocity areas

[Professor]

Even better get a copy of Blairs book.

Title?

[Competition CNC]

There really isn't any lower velocity areas in these style ports.  Not much anyway.  the floor is slightly higher than the roof in the bowl, but its very insignificant.
When you start talking about old automotive stuff then theres big variances.  But this stuff is so damn good from the factory.....
On some ports having a texture to the floor is beneficial for cold startup on street engines. But thats mostly on automotive carb stuff.
These ports with fuel injection act quite differently. These modern bikes use very wide pattern injectors with VERY fine droplet atomization sizes, to promote fuel suspension.

I would like to see what the swirl looks like in the chamber of one of these Busa heads and compare it to a zx12r/14 tumble port head.  That would be very interesting.