Now you're talking.

Matching the ports, in & out, make a big difference. You may not see big HP #s but the throttle response will be waaaayyyyy better since the flow is more efficent.
If you do a dyno, you will see the difference, not so much in HP, but in how even the HP & TQ numbers are.
Optimization Todays word....

 

I appreciate this post..... what I usually bring to this forum is that I am just the average guy professing little knowledge except what I have learned from "hard knocks" ....... the reason I start most threads is to stamp out my own ignorance by encouraging discussion..... generally it works very well.... I have learned a lot...... this is one of those "of course" kind of things for many but "WTF is that" for many as well...... I hope through my ignorance and subsequent education that my "showing my ***" helps others......

 

So are we to assume that the megan is staying on the car?

 

Port matching in not only about creating equal size & shapes; transitions and anti-reversion steps should be incorporated as well. Follow the rule of smaller exit enters larger entrance in the direction of flow.

As on the exhaust side, the intake manifold should be matched to the intake ports at the time headwork is performed. This means the intake manifold exit port should not exceed the size of the intake port on the head but not be so much smaller that turbulence is created by the large step. Buying a modified intake manifold after the fact is risky (especially with hand ported heads) and may cause more barriers than flow improvements. The exception to the anti-reversion miss-match rule would be the port channel for the fuel injectors which should be an exact match. If you were to remove the injectors and look down the holes on a stock head & IM, there will probably be an offset match for at least one of the channels although usually there is a shift across all of them. Core shift is common on every cast formed part on the MINI including the head.

 

I can conceptually understand why you would want to match port size on both the intake and exghaist side and why you would want to maximize flow and flow quality.... I still would love to know how you actually quantify things like Turbulence, what constututes constructive vs. destructive interference and how you actually quantify things like swirl and mixing and the like... Anyone?

 

Most heads are not conceived of on the drawing board/computer and most are not evened CNCed -- the makers have no ability to reproduce the shape. The only shop that I am aware of that can and does measure factors such as swirl and tumble is Wegner Motorsports. And that is why racers rely on them.

 

take a look at some of these articles and get an education; larry has been doing this for quite a while.
http://theoldone.com/articles/The%5FSoft%5FHead%5F1999/
http://theoldone.com/articles/h22a%5Fhead/
http://theoldone.com/articles/b16a%5Fhead/
http://theoldone.com/articles/b16a%5Fhead/index2.html
http://theoldone.com/articles/Dyno_R..._roomfinal.htm

 

If you are addressing Precision concerning the difference between The Old One and Wegner I am not sure why. The differences between the two are as different as night and day.

 

It seems jlm was providing an example of another shop that uses modern equipment (computer and cnc machinery) and does measure/consider swirl, etc. Is it unreasonable to suspect there are others? Perhaps how shops use their equipment and the information garnered from measurements and experience is where the "night and day" differences come into play. I think this is a good thing. Listening to you and other knowledgeable sources help to alleviate some of the confusion when considering the options. My ignorance is profound and the learning curve is frustrating yet entertaining and I thank you and the informed others for taking the time to post.

 

this statement from dmh requires a response:
"The only shop that I am aware of that can and does measure factors such as swirl and tumble is Wegner Motorsports."

dmh may not be aware of other shops measuring "factors such as trurbulence and swirl", but these shops are out there. If you look at Larry's site and read the articles about quality of flow, laminar flow bench testing, "roller-wave pistons", piston dome shape, head and engine building, a lot can be learned. I particularly like the dyno room and building the 2 liter engine. Reading about his "soft-head" and the roller-wave pistons is enlightening, and that insight was developed in the nineties, if not earlier. If nothing else, the site is loaded with great pictures.

 

Thanks for the links There's some good reading here!

 

Maybe I missed something but has anyone ever addressed the importance of a header that is matched to the new head's exhaust ports?

In the two years that I've had my Webb head and Miltek header, I haven't heard any vendors mentioning this subject...what good is an enlarged/ported head when it's bottle-necked to a stock header or an aftermarket header with stock sized exhaust openings?

 

yea just look one page back.

 

Oh that guy Bob We were discussing that issue just yesterday...didn't know he beat me to it...again

 

This is one of those "assumption" topics.
Those that know assume everyone does and those that don't, of course, don't know to ask.

 

I have had an Endyne head in the shop as well as a few others. The differences entail the port shapes, valve seats, guides, retainers, locks, the valves stems, shape, size, weight, and the valve springs. These constitute major, not minor, differences.
The other shops you might be referring to are out there but not available for our use -- they are for race teams. Endyne simply does not have the technology available to it that Wegner does. Cosworth is the only one that is comparable. It comes down to resources -- financial and technological.

 

To the best of my knowledge only the Stahl header addresses this issue. From what I can tell all the other headers are a round tube welded to the flange. Most of the primaries are too small and too short to be of any real benefit.

 

OK so if one were designing the optimal setup for an MCS-

Which combination would be recommended:
Which intake?
with Webb head and cam
Which header?

Probably the exact cold air intake doesn't matter that much.
Probably the exact cat back exhausts doesn't matter that much- should be free flowing.

But one problem is which header (and maybe which CAT if using OBX or supersprint)

If one wanted to keep the stock header with upgraded cat back exhaust, then would it NOT be useful to consider the head/camshaft upgrade? Just thinking of the entire upgrade package and how everything works together.

 

Look at the difference between the Webb head exhaust opening and the header flange



Inside line is the flange...

 

How are you planning to do the expansion of the ports on the header - die grinder/ dremel?

 

1/2 hp Carbide die grinder

 

and it's usually an expensive lesson that goes like "I just bought XY and Z that are supposed to make 50 more HP, and I only got 12. What happened?" As one learns that digs in, you find that a bunch of mis-matched parts have eaten up a large % of of the performance that had been paid for, and you have to do the work AGAIN to fix it..... And then, in the future, you'll never, I mean NEVER put on stuff like this without checking! While it's not perfect, you can use a dremel or a die grinder to smooth off the shelfs, so you aren't grossly blocking the flow....

But anyone that finds stuff like this, don't feel bad. I haven't met a single person that didn't learn the hard way!

Matt

 

I must be getting old because this never occurred to me...hey...I was learning this as I went like everyone else...I'm just surprise that none of the vendor mentioned that this was an important key to optimising their "SUPER HEAD JOB":impatient

Again...is it just me or did I miss something after 5000+ post? Why hasn't this been discussed before?

 

It is rather odd, you would think the supplier of the head would say something about it.

 

I’ve talked to a few of the vendors about port matching; Randy Webb (vendor for the head and header topic of this thread) had some very good input over two years ago so I know if a potential head purchaser would research, plan & discuss, and be willing to participate in the process the miss-match pitfall could be avoided. One could walk into a book store and do a cursory read through of an engine blue printing book and get this kind of guidance.

I had written communications with Bob (SpiderX) over a year ago on this very topic yet he didn’t take the effort to verify compatibility for himself. It took someone with a vested interest in the performance of his vehicle to catch it; as is the responsibility of each person that chooses the aftermarket performance path.