Would it be to late to run this idea by Shad for his upcomming Heads? (maybe he allready is aware of it's gains)
Intake velocity is old news. The fact that over-sized ports (without the rest of the engine configuration to back it up) is a loss of power is also old news. Taking advantage of high intake velocities via inertia tuning is also old news.
He's just adding hype to the whole thing and calling it new again. Whoopie!
Small ports have a lower potential for horsepower. Always. However, like anything else, to get the full potential, you need the whole engine configuration to be in tune with itself. If you have huge heads, but no engine to back it up, then you have less power than if you had smaller heads and the correct engine to back it up.
The largest porting level of our upcoming Porkies cylinder heads are friggin' huge. The intake and exhaust ports and valves and chamber are all designed together to be appropriately sized for one another. If you put these heads on a little 2056-2270cc engine, you will have a horrible engine combination that will make less power than if you used a smaller porting level of Porkies. But, if properly configured with the cam, intake, exhaust, and enough cc's to bring the redline back below the stratosphere, hold on tight!!!
Take care,
thats what i was thinking
maybe the bikes he works on have huge ports for the engine size...BUT!!!...vw engines(and maybe some other ones)have an exagerratedly(?!?) small port to begin with...
because if this was true(with any engine)...WOULDN'T A 1600(OR 1200 FOR THAT MATTER) SINGLE PORT HAUL SOME SERIOUS A$$!!!!!!!!!!!!!
AND HE IS ONLY SEEING SMALL GAINS ON A SPECIFIC ENGINE...WHAT IF HE WANTS HUGE GAINS IN HORSEPOWER...SEEMS WEIRD TO HAVE SMALLER PORTS ON A BIGGER ENGINE(HUGER)
I THINK MAYBE ITS JUST THAT THOSE BIKES MIGHT COME WITH OVERSIZED(OR INCORRECTLY CONFIGURED PORTS)???!!!???
The ring seating "trick" is as old as dirt, and was a poorly kept pro stock "secret" for decades.
(Super fine hone the bores and hammer down, check blow by, lather/rehone repeat if it isn't good enough)
The rough port thing is also an ancient time honored practice on street motors, and applies to non drag moros of any sort--peat HP is not everything.
There should be some arbitrary number that averages HP across the power band, at some describable point, like 6db down or such. (log scale)
This guys points all could be applied to any motor, and is the reason our T4s feel so good-power everywhere.
I am thinking of subscribing to this guys newsletter just because I like the way he thinks.
Addendum to Newtons first law:
zero vehicles on jackstands, square gets a fresh 090 and 1911, cabby gets a blower.
EZ3.6 Vanagon after that.(mounted, needs everything finished) then Creamsicle.
69bug wrote: AND HE IS ONLY SEEING SMALL GAINS ON A SPECIFIC ENGINE...WHAT IF HE WANTS HUGE GAINS IN HORSEPOWER...SEEMS WEIRD TO HAVE SMALLER PORTS ON A BIGGER ENGINE(HUGER)
I THINK MAYBE ITS JUST THAT THOSE BIKES MIGHT COME WITH OVERSIZED(OR INCORRECTLY CONFIGURED PORTS)???!!!???
Beeing a superbike mechanic he has to follow rules, so bigger valves could be out of the question that way...
he warns about making the porting to big, the choke point of the post (where it bends) has to be 65% of the valve size, making it a "D" shaped port at that point... sure he mentiones valve sizes but the porting is beeing done in a relation to the valve size, I think that's the key to his story.
What I would be interrested in if anyone has done the porting that way, instead of one big size all way up to the valve...
I still believe in bigger valves though... just a bit different porting
Well for Chrissakes even Berg (see the blue book, or better yet don't!) figured out that hogging out the ports as much as possible isn't the best thing to do. The cylinder is only going to accept so much volume of air until the pressure inside is equal to the pressure outside, no matter how much it flows on a bench. If this happens too soon and the compression stroke begins (with valves still open because of your massive cam) then mixture will be forced out. Of course at hight RPM, these ports have less time to do this. It comes down to figuring out what your displacement and cam combo needs for the RPM range you can use. Like Jake says, "its all in the combo!"
But his site drives me nuts. Its written in that same condescending tone as penis enlargement ads (Uhhh, honest its for a friend!) and Berg's site. "5 minutes ago you didn't know this, but only an idiot wouldn't understand it!"
Well, make that a '16 valve VW (aircooled) head' according to him...(!)
At his website you can further see a type 4 head with type 1 ports sort of welded onto them ???!!!
Anybody have any experience with those ?
Walter
I have talked to several automotive engineers in the past. They all tell me that you cannot have a 'real' four valve air-cooled head. There is not enough metal left to cool the head if the engine is making four valve HP.
That said, you might get away with it in a drag engine. The heat buildup in a drag engine is only for 10 to 15 seconds (or whatever).
On the street or in a long distance racer; no way!
I think he is misusing his idea of "scientific method". He points out that when a tuner enlarges the ports, bumps the CR, biggers the cam, etc. and then says the power gains are due to bigger ports, that the thinking is faulty because the big porting was part of a package.
#1, I really do not believe anyone would actually make several changes to a combo and than say the power gains were due to 1 change (the porting).
#2, His experiment on the 600, of making only 1 change, (reducing the ports) is not (as someone pointed out earlier) independant from the rest of the combo.
He needs to do this to a wider range of combos to convince me. And even then, he would only be finding the correct size for the rest of the engine. Face it, at some point the ports have to become too small!
I didn't really understand the part about the 3 phases of intake. It seems to me that what I believe he is refering to is influenced more by the cam.
Ron, I agree with what you are saying. Also...there is absolutely nothing new in this guys writings. Its excellent, but very well known and common among those who port heads...for high end performance for a living so I'm told. So why arn't all of these people talking about it? Because most high end head porting people do not have to advertize....they have lots of work. Also...they probably would not want to advertize. If everyone knew how they did it...their customers would quit having an advantage ...and get could also their work done anywhere.
Porting is not just for flow volume. It is for velocity as well...and, that and the flow volume may be specifically tuned for a given rpm range at a given valve lift and diameter. It is also as the gentleman mentioned, for shaping the dynamic of the airflow....ie: is it straight air? does it tumble? how much? how much turbulence? There are many times when material is ADDED into ports to affect a change in entry angle or speed. Texture and even shock ridges may be added.
Also texture to the ports does not automatically benefit any or every engine. In some fuel injection set-ups...its actually a hindrance. There is NO generic formula or method for porting...and there never will be. Ray
If I can get off track a little, (the article refered to thinking outside of the box so this does relate...)
Power to weight ratios are relied upon to predict rate of accelaration and things like 1/4 mile ETs. Fact is down the track the car is not acc at a linear rate. As rpm increases Hp increases and the rate of acc is also increasing. It does this repeatedly in each gear. How is it that peak hp and vehicle weight converts to Meters/Sec/Sec when the car is spending only a fraction of its time making peak power?
O.K maybe I think too much, but If I am actually on the right track with this, how would you design an engine with this in mind? Would you want a broad power band with the maximum area under the lines on the dyno chart? Would you sacrifice peak power to accomplish that maximum area below the curve?
(maybe he allready is aware of it's gains)
