without cncing can you generate the patterns and markings that they use in their heads? if you haven't seen the inside of one they use some clever engineering to improve velocity and flow. while the benefits won't be crazy... (i haven't seen ANY crazy head numbers that justify the prices that are out there)

the fact is the labor is extensive, by hand and by cnc machine. so.... if you want the most out of your car you need to get it, otherwise... you don't.

 

this statement is rather rash...

if flow numbers don't mean anything from head to head... then which head are you buying? the one made by your guys on a monday? wtf are you trying to say or prove? besides that nothing can be proven?

and about the theory... that's exactly what you're paying for... who says that your head made by your guys is performing as well or better or justifyibly-in-price as well as the cosworth head?

seriously... if you don't want it... don't convince yerself any further.

the fact also is that these heads have been successfully campaigned on at least three race cars that i know of. muellerized, aspec and ams.

how many race cars has abc shop done? and if the valves work on these cace cars... what's not ok about them? you're the one talkin' about don't spend your money lalala, maybe they don't wanna put in valves that make things more complicated when what they put in works.

 

i'll post dyno charts as soon as I get my car dynoed...but when i do you will say that whatever gains i have were from something else and the head wasn't a big factor...you are the one ranting so get over it.

 

The patterns and markings can be generated by hand if you wanted to. However, IMHO, the specific design used by Cosworth isn't any better than what you could generate with the right bit in the hands of a professional porter.

If I want the most out of my car, how do you know that I need this? What proof do you have that this is it other than the fact it's a Cosworth product?

 

Plenty can be proven.

When you take a head to a machine shop to have it ported. They should flow test the head at X" of water. During and after it is porting the same guy should flow it again on the same machine at the same inches of water. By doing this you can at least get close to measuring if there are any gains from porting. The best way would be the same guy would flow the head before, during and after on the same bench, in the same conditions, and the same inches of water but this is not always practical.

When a manufacturer gives you a flow chart, like Cosworth's, and doesn't provide basic information such as how many inches the head was flowed at, then the data is trash. In addition to this, a savy person would want to know on what machine and the conditions as well.

This is why I said the information that they give you might as well be toilet paper.

I do, because I have the data to back up my conclusion. I can see a before and after flow chart with critical testing data and also before and after numbers measured against other heads that were ported. Where as with Cosworth I don't have this data and apparently neither does anyone else. Everyone seems to be concentrated more so on the fact that it is a Cosworth head instead of anything else.

If it performs better than the other professional ported heads and someone has the data that it does then excellent I'm all for it. However, no one has provided this information as of yet.

(does anyone else see the re-occuring theme in all these post? I ask for proof and everyone keeps telling me about a big name and faith.)

The fact is that while these shops do great work, they are capable of mistakes as well. These shops have the money to experiment and do research. If you follow everything they do, you would be broke within a few months. Because these shops are using and testing the heads now does it automatically mean that it will be on their cars two months from now?

Back in 1994, everyone thought it was insane to put anything over a 20g and 550cc injectors on a 4g63. The few shops that were around would advise all of their customers against it. Today would you follow that same advice even though, two of the guys that I can think of, still own shops today and sell EVO parts?

Lastly, can you tell me why the valves they put in their heads are so good? In order for you to tell me that they know more than I do and that their decision was right you would need to know why I was wrong. When you figure it out please let me know.

 

+1mm Inconel Exhaust Valves (2400 degrees max.)

I did not know that part- those must be some expensive exhaust valves! Inconel=$$$

 

http://www.supertechperformance.com/technology.htm

 

thanks for the link

 

IMHO, if you are taking your head to some no name machine shop you are taking a risk of actually making your head perform worse. I'm sure there are some very good machine shops out there, but do you honestly think the average machine shop or even a very good machine shop, has the engineering resources as Cosworth?

I think flow bench numbers are a good aspect to evaluate head work, but it clearly isn't the most important aspect. The most important aspect is the real world performance gain. We don't race on flow benches, just like we don't race on dynos.

A flow bench does not simulate real world engine operation. Dry flow and wet flow are different, a flow bench cannot simulate the effects of valvetrain operation, and the list really goes on and on. These are things that a true race engineering firm like Cosworth specialize in.

So in essence you can have xyz machine shop flow a head similar or even better than a Cosworth, but on an actual car, in operation the performance could be different.

Trust and faith really are the name of the game when it comes to machine work and engine building. I know I for one do not have the tools to measure run out on the valves or valve seats, the straightness of the deck, the installed height of the valve springs, ect... ect...

Doing these measurements are extremely tedious and I believe paying a premium from an engine builder with a world class reputation ensures that they did it correctly, or that they even did it at all.

I do agree that people often over pay for big name marketing brands, but this isn't a simple strut bar, downpipe, shiftknob, or exhaust. You truely are paying for race engineering quality.

 

I know of a shop that has this Cosworth head in their possesion. I sent them a link to the flow graphs.
https://www.evolutionm.net/forums/sh...=cosworth+head

This was the response....

"Interesting. Their flow figures don't agree with what we've seen.....but they didn't list the pressure drop they tested with either."