I'm assembling the latest compressor tomorrow. We just got the parts in for a new test bench that we are building. I also now have a digital camera so I can keep you up in pictures. Also I have a website under construction you can use. axialflow.com
I don't know how to use it yet so the learning curve is something we have to live with. Until just now I didn't think about putting updates on it. I guess I could make a page for that. I'll have to talk to the man who is helping me with it.

I plan on doing the install in my own Rx8 within the next six weeks or so. That means the begining of an install not a complete running car. These things always present problems you didn't expect. An ETA for the running example is your guess as well as mine.

Thanks for your interest. I'm working on it. Just as soon as I can get CARB done on the Mazda I will sell it and buy an S2k to work on.

 

Bump
Anything new going on with the project.

When will the Short shifter for the S2000 be available for purchase?
Your web site has the availability listed as "In testing stage for sale in about a month."
From the pictures it would appear that the throw distance will be slightly less than the C's ShortShifter.

 

To everybody that is reading this post Richard is still actively contributing to this thread. He has been really busy with the development effort of his supercharger.

Please be patient this supercharger will be worth the wait

Quote from the Rx-8 forum

 

FYI S2000 owners
Question and answer fro the other forum

QuestionI am going to post a quote found in the fuel economy for supercharged/turboed 8's

Just wondering if the supercharger you are designing will have these same problems/characteristics.

The quote is from a turboed RX8

"The boost starts at 3000 RPM, and when you are cruising at 75-80 mph we are right around 4000 RPM, so the turbo is running. Not much but it is twirling so heat is building up. Since it was on cruise control, I was not giving it any throttle. Just went to high 70's set the cruise control on, & watched the EGT gauge. It steadily moved up about 200 degree C, and I decided to turn it off. It is the fact that our cars are running at 4000 RPM in 6th that the turbo is not good for the CC, unless you are doing under something like 65 mph. Like you said, we need a 7th gear, or we can't really use crusie control for the turbo."

Answer from Richard
This is typical of a blow through turbo system. You are still spinning the turbo even if your throttle is closed. There will be no manifold pressure as the engine is using more mass then the throttle lets in. Therefore vacuume. But you still are restricting the exhaust so heat will build up. There is in all likelyhood room for safe operation and you may be panicing early.
The point is made though about turbo heat, it has to go someplace. You need the heat, remember that is what is driving the compressor. But from this you see that it is not free energy as some like to claim.

If they were to use a drawthrough type system this action would be reduced somewhat. In my system this in not going to happen at all. We have no connection to the exhaust so we build no heat there except when we produce more power. During cruise with the axial flow system the engine acts just as it did before. It has no way of knowing there is a supercharger on board. Idling in the vacuume of the duct between the TB and the ports it takes no power, does not effect fuel mileage.

It is my intent to leave the entire fuel and spark system intact. It will control the engine just as it did before the SC install. When the manifold goes positive the auxilury injectors add fuel as needed for the extra air. The spark timing is something I haven't worked out yet. That will be the only place I see some sort of piggyback computer controls. At the present time I think we can use full timing with street boost.

The added homoginization of the axial flow blading is going to benifit the rotary more then it does the piston counterpart. Just think how much mixing can be done by hundreds of blades going hundreds of MPH. All reacting against static blades facing the opposite direction.

Back to your question, no this system will not do what your turbo is doing.


My comment
I looks like just maybe that richard will not need to pull spark timming when running street boost due to the atomization and homoginization of the fuel as it goes through the supercharger.

 

If this means I can one day own an S2000 that creates sonic booms, count me in!

 

Actually should the tips reach the speed of sound that would be a bad.
Sub speed of sound turbine blade design is completely different than that of a supersonic design. Remember Richard is (over simplified) using a wing and aerodynamic compression to create boost in this case. Some where in the RX-8 forum this question regarding supersonic compression was brought up. When a wing (aka axial rotor blade) reaches the speed of sound the resulting sonic boom could cause damage the compressor its self or worse cause parts to fly off and be ingested into the engine. Think of it this way. Look at a compressor map for any type of forced induction.. There is a limit to the amount of boost the compressor can generate. One of the factors that limits this is the speed of the compressor turbine blades. When the wing tips approach the speed of sound turbulent areas are generated which could cause loss of compression abilities or worse loss of flow across the wing. Think about WW2 pilots than when in a steep dive lost the ability to use their control surfaces due to the compressibility shock waves that was taking place on the control surfaces.

 

Richard,

Thanks for your patience and the information you've given on this forum.

It seems like you are still getting a lot of questions about pressure/flow characteristics. At the risk of sounding presumptuous, I'll try to pitch in my two cents. My background is in industrial turbomachinery and combustion engineering . I have 10 years of experience with anti-surge controls for centrifugal compressors of 1000 hp up driven by gas turbines and recips.

Perhaps it would help to explain the difference between ACFM and SCFM. The air charge density explanation that you offered earlier seems to have left some members in the dark.

The ACFM (actual cubic feet per minute) flow rate through the motor is the product of the displacement of the motor times its speed. This number doesn't change due to atmospheric pressure or temp, manifold pressure or temp, or anything else. This is what you referred to as 'displacement is displacement'.

The variables mentioned above do change the quality (density) of the air, and thus the SCFM (standard cubic feet per minute) flow rate of the air. This is flow rate with the fluid corrected from flowing conditions to standard pressure and temperature of 60 deg F and 14.7 psia). This is why intercoolers exist.

Superchargers and other parts affect the quality of the air as well as the manifold pressure. But their ultimate goal is to increase the SCFM flow rate. The beauty of this compressor is that since it's a draw through (compressor behind throttle), it only needs to compress the amount of air that the engine is consuming (very little at low engine speeds). At low throttle opening, there is very little air moving to the engine. So the supercharger is doing very little work, and adding very little heat doing it. It is still moving air, but very watered-down, diluted air.

I am curious to see the performance curve for the S2000 compressor when its finalized. I assume this is a true axial compressor with no surge line. Or is it a mixed axial/centrifugal compressor?

Hope this helps everyone.

 

[QUOTE=snakeeater,Apr 27 2005, 02:59 PM]
I am curious to see the performance curve for the S2000 compressor when its finalized.

 

I'm also very interested to see the power/tq curves once the charger is completed. I'd love a twin-screw setup if someone would/could develop one for the instantaneous and broad tq band. Richard stated that the boost build up is linear, which is better than a centrifugal, but seeing the low- and mid-range gains would be the deal maker or breaker for me for this type of SC.

 

Here I am by demand. I'll go to the questions first. Thank you Snakeeater, dare I ask where you got that screen name? Anyway your explaination helps I'm sure. I'm not the best teacher or I'd be on campus someplace looking at coeds and playing in the lab.

This is a full axial design as you can see on the begining pages of this thread. Currently they are being built in 4 and 5 stage design. These have axial rear inlet and radial outlet. Within the front housing/volute there is a planetary gearset.
The redline is 50,000 with a peak design point of 45,000.
You don't have to worry about going sonic until well up in the 50's.
Sorry no sonic booms. If you need one crack a whip.

With the 4 to 1 ratio of the gearset and a 9000 RPM engine redline it takes a 1.25 pulley ratio which allows for a good size upper pulley and good belt wrap.
Ratios can be adjusted up or down from there quite easily.

Currently we are finalizing a new test bench with 100% duty cycle capacity. It has a vari speed drive and a gearbox with watercooling. We have added a drysump system with variable pressure so as to relate to the car. There will be full intrementation including CFM, temp, pressure, air speed and direct reading by lazer of blower rpm. Later we will make the blower base swing with a strain gauge to measure torque.

I said later as we have enough to do now and we can calculate the HP used.
We can leave this thing on forever if we want fior long term testing. It's heavy dudy, 1700lbs worth. I'll post pictures when it is done.

We took delivery of our brand new Rx8 last week. This is our first install test car. One car at a time and once this one is done we will sell it to make room for the S2k. I know we should have done the Honda first as it is easier and would have given us info we could use on the others. But that's the way it goes, I know you want it right now but the S unit will get done a lot faster then the 8. The ECU isn't as hard and there is a lot of room. One thing that might be harder is we may have to make our own intake manifold!!!

I've developed these before and it is a time consuming task. You could just build a log with tubes sticking out or you do it right.

I'm on your side, I just got use of a S2000 for extended testing of our shifter kit. They are a lot more then I thought they would be. I can see the need for just a tad more power though. It looks like the basic platform was designed for some more. I honestly don't believe that guys putting 450 or 500 hp in these can really get much pleasure out of the car except drag racing. It's just to small and short to bend around corners with true utilization of that power.

Besides I hear everything else breaks. So what is the ideal power? I don't know and everyone has a different answer. My plan is to get what I can with the stock shortblock and compression on pump gas. After that there will always be guys that are willing to spend the time and money to go further. I can work with that on an individual basis but that becomes one off installs and the price is relevent to the custom work involved.

I'll also post here some pictures of the 8 as we get going. That will give a better idea of how these things set up as it is different from all the others. I don't mind the questions, it's just I don't check this forum but about twice a week. If I missed anything I'm sure you guys will let me know.

You make me feel a tad guilty about not getting here often enough but it could be worse, the Rx thread is close to 120 pages.