Small Intake Ports

[gazza414]

Just wanted to throw this into the "bullring" for comment .

Not that Stock


Modified

[crazybill]

yup , thems intake ports allright....

who did the work ?

[gazza414]

Bill, whats this website on the bottom of your sign on????..maybe you might want to elaborate on another post what you are up to?

[crazybill]

Oh I bought out performance porting awhile back . Ive been working with Jason Barnett (former owner) for some time now porting heads . I just recently changed the name and just yesterday opened an advertisers account here on the site .
Im still working on the new website . Ive got five heads sitting here done i need to get pics of for the site and four more in  line to be cut . I have a superflow flowbench for testing .
 I really love doing it too .
I did have to put a wall up between where the head shop is and where I build motors though . 
Forgive my website , its my first one and i did it in an evening
I should have a site banner up soon as dolphin finishes it .

[gazza414]

Oh I bought out performance porting awhile back . Ive been working with Jason Barnett (former owner) for some time now porting heads . I just recently changed the name and just yesterday opened an advertisers account here on the site .
Im still working on the new website . Ive got five heads sitting here done i need to get pics of for the site and four more in  line to be cut . I have a superflow flowbench for testing .
 I really love doing it too .
I did have to put a wall up between where the head shop is and where I build motors though . 
Forgive my website , its my first one and i did it in an evening
I should have a site banner up soon as dolphin finishes it .

Good stuff Bill  and all the best with the new business venture.

Have you looked at or experimented with welding and or expoxy 'ing up ports and going against the "grain" so to speak rather than OPENING them up ?

[crazybill]

sure ! mostly in the roof area .

youll get alot further shaping for velocity than cutting for flow !

[enginetuna]

Have you looked at or experimented with welding and or expoxy 'ing up ports and going against the "grain" so to speak rather than OPENING them up ?

Are you saying that some people actually open up the busa intake ports????  LMAO.  No wonder they all make shit power

[whtrthanu]

are you guys serious with that comment??............
I hope your talking about a stock bore motor, because if you guys are talking about a big motor, I think you would have some low power with that port size

[enginetuna]

are you guys serious with that comment??............
I hope your talking about a stock bore motor, because if you guys are talking about a big motor, I think you would have some low power with that port size

Why?
Isn't power related very closely to the port area profile?
Put a small hose pipe at the bottom of a 300 gallon barrel and it will dribble out.  Put a 300 gallon hose on top of a hose and it will dribble out.
A port will only flow what the valve curtain area can support, anything bigger is dead space and poor throttle and transient reposnse

[crazybill]

There is no "one size fits all" . combination is the key .

[whtrthanu]

Your right to a point...........if you put a head that runs great on a 1397 with a certain port volume and a curtain area or choke
that is a particular size, if you run that on a 1600cc motor compared to  the same head except for so called dead air or extra volume, the head with the smaller port will not make nearly the same power.......
It also WILL NOT hurt the velocity as long as your curtain or window area < total V/A

I think your statement about putting a small hose on the bottom of the barrel is backwards, but I get the point
you put a small hose on the bottom of a large barrel and the water will be pushed out pretty damn fast!!!!

[DarkFalcon]

For a number of reasons, high port speeds at the window or minimum CSA offer performance benefits. There is a point, though, at which port speeds can be so high that fuel separates from the charge and or pumping losses are incurred. Some refer to this as choke. The velocity is not free because even though the piston is in descent an extemely small port will act as a brake on the piston giving rise to pumping losses; like sucking on a small straw. In SAE literature this is usually taken to be .55 of the speed of sound......but I believe a properly designed will support speeds in excess of this stated limit. A port with an expoxied floor not only will increase speed but can effectively alter port geometry changing the regime that exits between flow diretion and the valve. In theory, each CID/RPM package should have its own port sizes.

[whtrthanu]

The air flow will pick up when raising the floor, we know it works, the only part about doing it is that it shrinks the port....If we could raise the roof to make up the loss it would be great.....The castings are limited in what you can do.....so you have to sacrifice, you loose alittle but gain alittle.........thats why there are some many ways to port a head.........everyone has there own style, and formulas that they use......
I have been doing them one way for a long time and will keep on the same track......it seems to be working for me.........
a million ways to skin a cat

[DarkFalcon]

Exactly. If you raised both the floor and roof, you would be making it more of a "high" port and less of a "straight" port.

[mike46]

Your right to a point...........if you put a head that runs great on a 1397 with a certain port volume and a curtain area or choke
that is a particular size, if you run that on a 1600cc motor compared to  the same head except for so called dead air or extra volume, the head with the smaller port will not make nearly the same power.......

Word. Filling the floor "tricks" the long side into thinking the short side has as much area. That is a lot of floor in that port.

[enginetuna]

There is more to it even than port volume when deciding the port.  The shape is extrememly important, straighten out that huge bowl on the busa and you will see some good gains at peak regardless of the cc.  There is also the ramp of the port csa which is hugely important.  Same on the exhaust side, map out the port csa and you will be shocked at what it is like.  Then also there is where you want the power and what transient response is required.  A circuit motor constantly being dragged down to 5k rpm and then asked the accelerate repidly before beign dragged down again will usually be much faster will a small intake that sacrifices peak power for response, whereas a drag motor is going to need a larger portion of top end torque without the small ports responses.  Like you said, many ways to skin a cat.

[DarkFalcon]

Here is a map of the Busa exhaust port area along with a couple of others. I did not undertake the work and it is only half the total port and begins at the seat. I have difficult in reconciling the first data point with what I believe is the throat area; I believe it should be larger and maybe something was lost in measuring the rubber mold. The horizontal axis is simply station reference points. Enginetuna, with respect to the intake bowl, I believe Suzuki is managing speeds and pressure through shape; the larger bowl slows the charge down and increases dynamic pressure.......thereby increasing the pressure differential between the port and the combustion chamber at IVO. I am not disagreeing with what you said and, if anything, reinforces the notion that there is variety of means of skinning the cat.

[enginetuna]

Yes chamber to throat to port csa needs to be a smooth transition.  Look at the de Laval nozzle.
I always fill the bowls now as do most superbike engine builders that i've seen work of.  Even yoshimura kit manual for 1000 says to do it.  But then the busa doesn't rev as high and a straighter port becomes more critical when you increase the rpms.
Its great that we can all talk about this stuff on a few forums because very few people in this trade will talk to each other truthfully face to face.

[enginetuna]

Also, forgot to mention, there is a link on one of the recent threads on speedtalk about intake port design and a honda patent.
Ah, here it is, http://www.uspto.gov/web/patents/patog/week09/OG/html/1315-4/US07182057-20070227.html
Weird thing is, that looks like the cbr1000rr port but again all the superbike tuners are changing this area and opening it up a little.  Weird eh?

[DarkFalcon]

It's interesting you mentioned the Laval nozzle because the image I posted was posted in the context of supersonic exhaust ports and, of course, this means Laval. I'm not a porter but I pick-up pieces of info here and there and then try to correlate these to what I get from SAE papers and then try to draw nice tidy pictures.

[DarkFalcon]

What sort of guidance does Yoshi offer.....sizing or whatever.. and what filling material do you use?

[enginetuna]

The picture from the yosh manual is on this page
http://www.gixxer.com/forums/showthread.php?t=162399&page=3

I use belzona 1111 and sometimes jb weld.  You can also use loctite metal set and devcon aluminium putty.

Search through the NACA papers.  There are some good ones on rocket nozzle design

[DarkFalcon]

Thanks. You may find this interesting:

http://www.engapplets.vt.edu/fluids/CDnozzle/cdinfo.html

[mike46]

The picture from the yosh manual is on this page
http://www.gixxer.com/forums/showthread.php?t=162399&page=3

I use belzona 1111 and sometimes jb weld.  You can also use loctite metal set and devcon aluminium putty.

Search through the NACA papers.  There are some good ones on rocket nozzle design

The Devcon Ti epoxy works well too.

[gazza414]

yup , thems intake ports allright....

who did the work ?

Bill the work was done in NORWAY on a R6 some 4 or 5 years ago

prob ET is aware of this and in particular for a bike that needed throttle response


Norway's Kai Børre Andersen dominated the European supersport championship this year with 4 wins out of 8 races. The points total tells the story: KBA finished with 153 points, and the second place rider had 93 points... !

Despite winning the championship with 1 race to go, Kai Børre went on to finish the last round with a resounding 6.5 second win in Cartegena, Spain !!

Kai Børre's 'secret weapon' ?? His Yamaha R6's unique engine set-up features smaller than stock, High-Velocity intake & exhaust porting by Jørgen Johnsen of Fast Bikes http://www.fastbikes.no in Oslo !!

Congratulations from all of us at Mototune USA !!

Read all about it in MC Avisa:
http://www.mc-avisa.no/default.asp?aid=4096
(in Norwegian)