In forms of competition racing and also with OEM manufacturers who must meet stringent emissions and performance requirements every last advantage is explored.

Prior to the recent economic melt down an entire industry has sprung up in North Carlolina and also in Indy to support the NASACR racers. I have read extensively in the Performance Racing Magazine and other trade publications of the great expense involved with even wind tunnel testing to gain slight advantages.

I agree with you, certainly when it comes to the extreme VE of say a pro stock or F1 engine, a lot of science and technology goes into finding more power.

I have seen the kind of computer applications and equipment which Ramone uses and he certainly has the right equipment to do the job properly. All that remains to be seen is what kind of results such efforts will yield in an application like mine.

In the past, the heads I used were all generated by old school head guys who did most of their work by past experience and eye. The head I am going to test is supposed to be a result of extensive testing and R & D.

Hopefully, I will continue to be able to afford to invest in additional testing and development on my Evo and continue to take it racing. The $$$'s keep adding up and its certainly not an inexpensive hobby.

 

In this hobby, its really hard to be a master of all trades.

While I do all my own tuning and wrenching, I would like to seek outside support on the more complex areas such as machine work and head design which require huge investments in costly equipment to do properly.

My goal is to try and team up with others who share the same commitment to excellence and passion for doing a great job in those areas such as head porting, cam design, body work, cage and safety equipment installation and machine shop services.

I can honestly say that my time in this sport compact field has met with a lot of disappointment and frustrations those times when I have had to reply on the services of outside vendors for those services. This was particularly the case back when I first started to modify my Subaru in 2001 and was dealing with a lot of people who were used to working on traditional V8 Detroit Iron.

I guess what I am saying is that the very complexity of the subject matter at hand dictates that very skilled and experienced experts be utilized in this area of the hobby.

Al

 

Good luck Al.

Too much book work in here for me, I previously had some respect for it but over the last few months have found it to be more worthless than I had ever imagined. Either there are a bunch of people with software and educations who are using it all incorrectly or it just simply doesn't work, I don't know which.

There is ONE way to find out what works. Build it and test it and by testing it needs to be on a dyno or track.

Good luck with your testing Al.

 

The good thing about having an Evo is the ability to simply call Buschur Racing and get parts which are fully proven to run 9 seconds on customer cars.

Sadly, as I have explored and continued in my Subaru STI addiction, Buschur is no longer there to supply me with with proven and tested products and I have been chasing my tail now to find the right parts and partners to work with to get Subaru set ups which can make 700 whp on pump gas and hold together. It sure is a lot easier being able to just pick up the phone and simply order a Buschur short block. Can't do that in the Subaru world. If you want a serious Subaru engine you have to build it yourself.

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Of course in doing so I have tried to apply what I have learned from Buschur into the Subaru - again sadly no race fmic for Subarus - I tired to find the next best thing. They don't make Buschur race fmic's for Turbo BMW's either. hint hint.

It was through one of these new connections that the concept of this cnc Evo head came to realization and in my hands - not to mention the generous support of Super Tech valves - a great company

Being an open minded guy, I am always open to new ideas.

Al

 

My bad, didn't mean to come off as a *****, just wanted to clear up a point or two.....But sometimes a little knowledge can be a dangerous thing.. dumbing down stuff for the masses can get alot of people in trouble, if a topic is too complex from someone to understand, maybe they will do a little google search and try to learn a little....
We can only hope..

On a different note:

David B., If people are using the software packages and getting crappy results from it, its pretty clear they are using the software incorrectly. On a well calibrated model as compared to a real dyno test, I have seen margin of differences of only 3-4%. ( ricardo 1D wave and 3D cfd vectis coupled simulations)

But that doesn't mean you can't actually test to confirm.. the simulations should be used to predict changes and get inthe ball park of the desired results you want... There is no subsitute for real testing... but sims can make that testing quicker...

 

4G63DSM, what aspects of the engine need to be simulated in order to properly design an intake manifold for an evo? Do you need to model valve events, cam profiles, cylinder head ports, etc?

Or is just whiping up a 3d model of an intake manifold and running some relatively cheap CFD software enough? Because from listening to you and Ted, it sounds like the real meat of knowing if an intake manifold is good is how it handles the pressure waves created from valves closing, and I don't think anyone in the Evo world is simulating that are they?

 

Yes, correct. Every "simulation" I have seen on these boards are mostly guess work..Not engineering but rather a nifty art project. They made some pretty pictures of events that never occur in a running engine. An intake manifold will never pull air through each runner at the same rate evenly. Never ever. Nor will it ever have have one pulling air through while the other three remain completely stagnant. Those two events should cover nearly every "simulation" that i have seen posted on these boards. Pretty pictures. Not really engineering. But, honestly, not all that bad, really. Here is why.

Now I admit, you can get close, and look for some problems using steady state methods as above, and even make a few improvements. Time and effort wise, it's a little bit better than trial and error. But only because you might be able to cut a few iterations out before the trial and error starts.

Yes, Crcain. Basically you would need Crank radius, rod length, piston diameter, compression ratio, ( to work out the kinematics of your swept volumes,) rpms, valve lift and duration, some idea of discharge coefficients at the valves. .mmm i thinks thats about the basics.... (and I may be forgetting something here......) Something like GT power or Ricardo Wave can take these and calculate the pressure drop that would occur in the cylinder when the valves open and close. This rapid pressure drop is the driving force of all the air that goes through that cylinder of the engine.

Do it more than one cycle, (720 degrees) and you get some waves. Make these waves bounce when and where you need them to and you can actually force more air and at a greater density into the cylinders than otherwise could get in. Do that and you just achieved over 100% VE via the resonance tuning mentioned among the previous posts. On V6's, and such, depending on firing order and angle between banks, a wave from one cylinder can actually bounce into the next one firing if it's on the opposite bank. Even more resonance, pulse wave or ram tuning, or whatever you call it. Now clearly, this is most important with NA cars.

On turbo's, this is clearly not the largest factor in making power. Psi is. On turbo cars are safe assumption is that nearly all the intake piping is darn close to a steady state affair. It's mostly OK to design this way. Simulations of a steady state nature will be match to some effect the results on a motor. A to B improvements are easily seen.

Don't throw out the first few paragraphs though, The Waves and Resonance tuning can still be used for additional improvements on turbo cars. Although, How, is up to you. You could choose to get that extra little of air in where you want your peak power to be. Or, do something a little bit different. Time those waves to NOT have a high pressure peak when the valves are open. Have the low pressure part of the wave at the valve seat before it closes. Let the boost take up the slack of pushing air into the cylinder, and take advantage of the low pressure, i.e. low density charge going in. Now that doesn't really make sense does it? Maybe, maybe not, but a change a gas' density, and the temp may change too. Some times a little colder temp of air can do wonders. It might be enough to slide under a knock threshold, or squeeze an extra psi out or two. Just maybe. Or maybe not. Believe it or not, both ideas are currently being used by real OEMs!

(This just turned into a rather long rant.... oh well.......)

 

Off topic but, DynoFlash why did you use the PT65 wheel instead of the FP one.

FP didn't use the P-Trim so it interests me to as why you switched it out.

 

Throat diamter is something that you don't play with. There's a direct relationship between the bore and throat, which doesn't change. An example being that when you use larger valves you need to have a larger bore. Also, the size of the valve exposed to the bore is directly related to the RPM at which the engine is going to be operating at.

The throat diameter dictates the velocity across the seat, you can make a big throat over 92% of the valve and you will pick up a lot of CFM but you will diminish the velocity which will reduce the KE and in turn will also cause a loss in the ram effect of the air filling the cylinder. Therefore, throat diameter is NOT something that you want to be playing with.

134 CFM per square inch of the throat is what you see in Indy or a well developed cylinder head. Formula 1 reaches up to 138 CFM per square inch of the throat. To achieve perfect flow one would have to get 146 CFM at 28" of water, which is simply an empty path of air with no valves, guides, or seat.

On the topic of making 1100rwhp at 40PSI with the Toyota engine (which I assume is a 2JZ), you are making 183rwhp per cylinder while Al is making 196rwhp per cylinder with a stock head. I remember that when Headway Performance built Justin Humphries' 2JZ they made 1600hp at 40 PSI. If my memory serves me right, that car went 7.0 @ 200 MPH weighing in at 2890 pounds. I always remember how Ramon used to brag that the cylinder head never once failed in two years.
I disagree as far as the flow bench only telling you that "hole got bigger". A flowbench is very powerful tool that allows to measure velocity, choose different cross section areas, and choose between different valve jobs. Even in this day and age, with so many power computers major manufacturers still use a flow bench. AFAIK, even NASA uses their manual wind tunnel which is essential a large flow bench.

As far as the combustion chamber is concerned, I disagree very much. Look at this way, if you can't get the air into the combustion chamber there is no power. Remember that the CFM alone doesn't make power, it's just air which allows you to use more fuel which in turn allows you to make more horsepower. Combustion chambers have a very small role in 4 valve heads. Power is found in a combustion chamber when one anyalyzes the swirl and tumble which we call mixing motion. This allows an increase or decrease in flame travel which allows you to either use more or less timing.
I disagree with what you are saying because you are not measuring velocity. Keep in mind that velocity is what controls the ram effect when the piston is at BDC and the valve is open, air is stilling moving into the cylinder. This fills the cylinder beyond its capability, which in turn is essentially what a turbo does (increase the engine's VE to over 100%)

The inconsistency from motor to motor is usually directly related to inconsistencies in each manifold.
Funny that mention that the valve seats and combustion chamber are more important than the ports, and then you mention that a formula 1 engine has 140% VE. When a Formula 1 engines acheives 140% VE it's at peak torque, which is about a 98% result of the port work. A Formula 1 cylinder head barely has a combustion chamber and essentially has no valve angles.

I actually have some pictures which I can dig up to show what I am talking about.
The 1500hp ECOTEC runs on 13.0:1 compression and more than 50 PSI. The reason why the port is not bigger is because the casting itself doesnt allow it, the ECOTEC is not an efficient motor.

Last time I spoke to Fritz Kayl at Katech, he outsourced the cylinder heads from CFE.

Red Johnson at Rousch Racing has said that Don Losito is reponsible for most of the major port design. From what I was told, Rousch simply cleans up or tunes the port to their specific application.

Being that it's a small world when it comes to head porting, I am curious to know who your friend is.

 

The 65mm Precision Turbo wheel is similat to a Turnonetics Stage 5 wheel - its an advancement on the so called "P trim" which is very outdated

Simply by switching turbine wheels I picked up nearly 700 prms faster spool up

Al

 

Thanks for your input Ramon

If I wasn't having so much fun breaking in my STI with 17 psi of boost I would be surely swapping the heads right now

It sure is hard to decide which beast to play with at any given moment

Al

 

The guys name that worked at katech was brett. Can't remember his last name. I only worked with him at indy cylinder head for a couple months.

 

Any vids , I just broke my tranny but unlike David Buschur I am not giving up on my suby. My new build tranny should be here in two weeks and I will be trying to break the VF series 1/4 record in a month .

 

Having a very fast Subaru takes more effort and skill than having a fast Evo. the Subaru can be very frustrating at times but when you have it well sorted its a very special feeling to have one as there are not many others with the determination and persistance to stick with it

I grew frustrated with my 02 WRX and parted it out for my '03 Evo, I am glad to have the opportunity to now have both the STI and EVo as they are really totally different in character but both very rewarding when driven very fast

Not mcuh on the road can hang with my STI when I am in the mood

Al

 

Yeah tell me about it Al.. 99% of the imports out there are not nearly as mod friendly as the Evo.. It responds to everything you do to it as long as your using high quality proven parts..

Trust me, i feel your pain.. I am 5k deep in my M5 all for 50whp.. LOL

Mike