Axial Flow Supercharger
01-07-2005, 05:23 PM
#1002
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I guess I meant to ask whether or not the AF supercharger can be used to extend the rev limit on the engine?
Does the 2nd paragraph of your answer mean that the unit is designed only for the stock rev range, and that airflow will stall or fail in some way for engine speeds above the stock limit?
Does the 2nd paragraph of your answer mean that the unit is designed only for the stock rev range, and that airflow will stall or fail in some way for engine speeds above the stock limit?
Originally Posted by Richard Paul
I don't think I understand your question. There is enough air to keep going but what would that have to do with the fuel extending itself further. Also I don't think that the fuel cut off is gradual. If it was so then you would have a fatal lean condition. The fuel cut off is used as a rev limiter. At least that is how and why it works on other engines.
Realize that the SC is an airpump as is the engine but the limit to the axial flow is tip speed (among certain other things) so overdrive ratio has to be built to put it's redline with that of the engine. If more air is needed then a longer blade must be designed into the blower. This is not done by the end user.
Some people have claimed that for a bigger engine you just add stages. In fact more stages could do one, the other, or both add more air or add more pressure. depends on which end of the compressor you add them. Added to the front, more air and more pressure. Added to the rear, more compression.
Realize that the SC is an airpump as is the engine but the limit to the axial flow is tip speed (among certain other things) so overdrive ratio has to be built to put it's redline with that of the engine. If more air is needed then a longer blade must be designed into the blower. This is not done by the end user.
Some people have claimed that for a bigger engine you just add stages. In fact more stages could do one, the other, or both add more air or add more pressure. depends on which end of the compressor you add them. Added to the front, more air and more pressure. Added to the rear, more compression.
01-07-2005, 05:58 PM
#1003
What it means is that you "gear" the supercharger to the top speed of the engine. If you run out of airflow you resize the blower. Simply put, you estimate the airflow of the engine at antisapated redline then get a supercharger that will flow so many times that amount to where you want to flow. Now knowing what the engine flows and what you want it to flow you know the pressure ratio required. Just divide the stock flow by the wanted flow and you have not really a pressure ratio but a density ratio.
Sorry to technical. Pretend there are no losses. Go back to what I said only lets say it gives you the Pr. Example: stock it flows 400 CFM and you want it to flow 600CFM then you would have a 1.5 Pr. Or 7.5 psi in boost. I have a hard time stating it this way because of the real world losses but I said pretend for clearity.
Now you look for a compressor that is running in it's higher efficency range at that point. Then you gear the two pumps to meet at the desired point. This holds true for all compressors even turbos.
I feel I havn't answered your question, have I? Let me go someplace else, do you mean can the engine be coaxed higher with an air pump helping. To a small extent only. The engine which is an air pump just runs into it's own wall of inefficency about the same rpm with or without SC.
This rpm limit can be extended by all the standard hop up things that have been around forever. these extend the rpm and then you rework you original calculations to find the right compressor. Sometimes as with turbos you'll not find the exact compressor you want. It's never perfect so you settle for a point a little down on efficency level.
After you absorb all of this you'll want to know that it must be adjusted for "losses".
This gets a little more involved but I have given the math for it in the begining of the thread.
Sorry to technical. Pretend there are no losses. Go back to what I said only lets say it gives you the Pr. Example: stock it flows 400 CFM and you want it to flow 600CFM then you would have a 1.5 Pr. Or 7.5 psi in boost. I have a hard time stating it this way because of the real world losses but I said pretend for clearity.
Now you look for a compressor that is running in it's higher efficency range at that point. Then you gear the two pumps to meet at the desired point. This holds true for all compressors even turbos.
I feel I havn't answered your question, have I? Let me go someplace else, do you mean can the engine be coaxed higher with an air pump helping. To a small extent only. The engine which is an air pump just runs into it's own wall of inefficency about the same rpm with or without SC.
This rpm limit can be extended by all the standard hop up things that have been around forever. these extend the rpm and then you rework you original calculations to find the right compressor. Sometimes as with turbos you'll not find the exact compressor you want. It's never perfect so you settle for a point a little down on efficency level.
After you absorb all of this you'll want to know that it must be adjusted for "losses".
This gets a little more involved but I have given the math for it in the begining of the thread.
01-07-2005, 11:40 PM
#1007
Bummed, but bring on OU!
With all this discussion of engine speed and turbine gearing and yahda yahda yahda, I get the sinking feeling that this will be another FI kit that will not be produced for the automatic owners (sounds like an entirely different compressor would be needed). Tell me I'm wrong, please.
01-08-2005, 12:05 AM
#1008
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Originally Posted by therm8
With all this discussion of engine speed and turbine gearing and yahda yahda yahda, I get the sinking feeling that this will be another FI kit that will not be produced for the automatic owners (sounds like an entirely different compressor would be needed). Tell me I'm wrong, please.
01-08-2005, 12:10 AM
#1009
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Originally Posted by G8rboy
Considering the auto tranny can't handle much more power, I wouldn't count on much... otherwise Mazda wouldn't have put the low power engine in to start with.
01-08-2005, 12:11 AM
#1010
Your wrong. Because I'm the compressor manufacture I can make it do what I want. First things first though, lets get the manual working. Honestly the only way we will do the auto is if it is not to far off of the 6 spd. If it requires new castings and such chances are we will not do it. But if it just takes some ratio change and an intake adapter then it might pay. It's just like anything else, the buck rules. Sorry I can't change that.
01-08-2005, 12:47 AM
#1011
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Originally Posted by RX8-TX
Is there a chance you are confused? I thought what Mazda didn't have was an AT tranny that could handle the 9K redline...And if anything, I would think that the AT would be a bit more sturdy than the Aisin 6MT.
01-08-2005, 08:21 PM
#1013
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Richard there has been a lot of talk on this thread about everything from Superchargers to pulse jet engines.
I was wondering if you could give an update on how the axial supercharger project is coming along and what problems you are still encountering with the unit in the car.
Sorry if this sounds pushy but the thread is starting to sound like a haynes manual for jet propulsion.
I was wondering if you could give an update on how the axial supercharger project is coming along and what problems you are still encountering with the unit in the car.
Sorry if this sounds pushy but the thread is starting to sound like a haynes manual for jet propulsion.
01-08-2005, 09:55 PM
#1014
I can't always tell everything we are doing. If I dare to tell you that our latest design is going on the dyno this week. I'm sure we are close as far as compressor section is concerned and I'll know soon enough. But the actual layout of the unit is still not firm. With this unit I can redesign it so the inlet and outlet change ends. It is a major redesign as every part changes.
So, to answer your guestion we are about to fit it to the car within the next couple of months. How many detors will be required no one can say.
So, to answer your guestion we are about to fit it to the car within the next couple of months. How many detors will be required no one can say.
01-20-2005, 12:58 AM
#1021
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Originally Posted by mcpheeg
Richard there has been a lot of talk on this thread about everything from Superchargers to pulse jet engines.
I was wondering if you could give an update on how the axial supercharger project is coming along and what problems you are still encountering with the unit in the car.
Sorry if this sounds pushy but the thread is starting to sound like a haynes manual for jet propulsion.
I was wondering if you could give an update on how the axial supercharger project is coming along and what problems you are still encountering with the unit in the car.
Sorry if this sounds pushy but the thread is starting to sound like a haynes manual for jet propulsion.
Big knackers, too. Two posts and he's laying down the law....
01-20-2005, 09:52 PM
#1025
Rangers Lead The Way!
Originally Posted by Richard Paul
Well Jon, you already have the speed record. Guess I'll just be gracious when it happens. Couldn't go to a nicer guy.
Lol.. first time I read that I could have sworn I saw " RICER guy ".. heh.. so much for my good eyesight. Oh boy, I should delete all my posts on this thread just so I catch up faster
just kidding. Thanks again Richard for letting me help you out with that shifter I love it.