Axial Flow Supercharger
02-25-2006, 06:16 AM
#2883
New Member
Originally Posted by Hymee
Especially for a litty skinny asian dude like yourself 
ROFL!
ROFL!
I am riding (that is cycling) to work (30 minute each way) now.
It is 5kg down 15 more to go.
Now I would like to see you do that.
I still watch this space a lot.
Most Japanese blower project is not processing fast either, and they have 20+ people developing it full time.
Hey I am talking about HKS.
Last edited by takahashi; 02-25-2006 at 06:18 AM.
02-25-2006, 06:25 AM
#2885
New Member
Originally Posted by Hymee
Good work mate! I reckon I need to shed 40.
I knew that once I get back on my bike, my weight will drop.
Just keep on working. You will get there.
In the meanwhile... I will nurse my Renesis to the day that a nice blower comes along (not driving much this days) :cry:
02-25-2006, 12:41 PM
#2887
It was said in jest but it is sorta real. Though in fairness to the Hymester my blower is currently about 4 lbs overweight. Due to that new front volute it needs a lot of running to get back down to something reasonable. When cast the thing will get back on track. There is just so much extra material on it I can't begin to start cutting it off. Haven't weighed it but it might even be as much as 6 lbs overweight.
So don't feel bad Hymee, it's easier to cut weight off of this thing. If you want we can put you up on the machining center and run a program of your choice. Of course we could just cast you.
Hey, maybe I just found my calling in life. I could open a shop in Beverly Hills and machine women into whatever shape they wanted to be. We know most of them have enough excess material to work with. Taka, can we sell the scrap? 
So don't feel bad Hymee, it's easier to cut weight off of this thing. If you want we can put you up on the machining center and run a program of your choice. Of course we could just cast you.
Hey, maybe I just found my calling in life. I could open a shop in Beverly Hills and machine women into whatever shape they wanted to be. We know most of them have enough excess material to work with. Taka, can we sell the scrap?
02-25-2006, 10:12 PM
#2888
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Location: Ottawa, Ontario, Canada
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Originally Posted by Richard Paul
I could open a shop in Beverly Hills and machine women into whatever shape they wanted to be. We know most of them have enough excess material to work with. Taka, can we sell the scrap?
02-27-2006, 11:12 AM
#2889
Originally Posted by Richard Paul
Hey, maybe I just found my calling in life. I could open a shop in Beverly Hills and machine women into whatever shape they wanted to be. We know most of them have enough excess material to work with. Taka, can we sell the scrap?
I can't believe you haven't tried that Fred. 
02-27-2006, 03:43 PM
#2896
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Originally Posted by rotarygod
The M90 even done properly isn't sized good for a rotary that wants alot of power. For a sub 160 hp 13B, it can give a noticable gain but will still only be limited to about 275 hp if you do everything right and take alot of things onto consideration. Most of the subpar attempts have only netted in the 220 hp range but as stated earlier they left alot to be desired in terms of how they were installed and setup.
I'm a member of www.miataforum.com , but I hang out at a few other websites in the interest of following cool and intriguing threads like this one!First, I'd like to say I'd really love to see this project come to fruition for you RX-8 owners (as well as the S2000 guys, perhaps?) Sounds like an awesome exercise in engineering, and one that has not had enough attention paid to it in the automotive aftermarket.
Secondly, the fallacy that the Roots/Eaton/Magnusson blowers are wildly inefficient and can't make a wit of extra horsepower ("Heaton"
), etc., has got to be the most rampant false rumor that travels through internet automotive forums. The positive-displacement, lobe blower has come a long way since the 1950s and 60s, and Eatons 4th and 5th-gen blowers are actually more efficient at "lower" boost levels (say, under ~6-8psi) than the twin-screw Lysholm/Whipple/Autorotors. In fact, because the twin-screws produce small amounts of internal compression, their outlet temps at low-RPMs and off-boost are also considerably higher than the Eatons.The MP62 is currently pretty big in the Miata community, as is the 1.2L Whipple (from two separate vendors). So far, even though the 1.2L has .2L more displacement than the MP62, the highest rwhp recorded by both vendors is roughly equal (just over 300rwhp). In fact, one forum member went *****-out with his MP62, spinning it to ~21k RPM with all kinds of water injection and all the tricks in the book, and was able to get close to 360rwhp out of that blower (which, according to the Eaton's product charts is about as much air as it can flow).
So, if people are only getting 220rwhp out of an M90, with almost half-a-liter more displacement, on their RX-7s, then something's not right. There's a metric ton of Miatas running around with ~170-250rwhp from the MP62 and 1.2L Whipple, and quite a few beyond 250rwhp.
Now, given all that, I'm not saying these compressors have centrifugal-like efficiencies, but they're certainly not anywhere near as bad off as most people seem to believe. On top of that, they're the perfect match for small-displacement, low-torque motors, as they give exactly what these engines are lacking. Why do you think so many OEM apps go with them?
Oh, and the MP62 vendor for the Miata community (www.brperformance.com) is just now releasing their MP62-based S2000 kit, and it's making ~315rwhp/218lb-ft...with only 6.5psi of boost
Anywho, just thought I'd interject my bit o' information as an outsider.
Keep up the good work, Richard, and show us some more pics
We don't really care what they're of...well, as long as it's of the engine or some cool piece of billet machined metal
02-28-2006, 10:10 PM
#2897
Registered
The problem is that the rotary uses about 10 lbs of air to make 1hp and an average piston engine uses about 7lbs of air to make 1hp. That would mean that a blower that is capable of making 360 hp on a piston engine can only make about 250hp on a rotary. Do that math. That assumes everything was done perfectly. Using water injection and "all the tricks in the book" do not add up to reliability or daily drivability. 170-250hp on a piston engine would only be the same amount of air as 119-175hp on a rotary. These numbers assume all things being equal of course. There are some things that can affect these numbers but they are good baselines. A rotary will dyno more than that to the wheels with no boost. If that's the average power level that the M62's are getting on average, that's believable. They're too small for a rotary.
There are ways to get more out of an eaton blower. You can machine new rotors out of a lighter composite material and make the tolerances tighter. You can alter the inlets and outlets to have a nice shape good to airflow and then time them to a perfect 120 degrees of rotational opening. You can change the bearings to give you bearings that perform better at higher speeds. The throttlebody size on these is huge in making more power. Go up to an 80mm and power will go up. Design the intake duct from the tb to the blower for good flow velocity. These things can all add up but if the blower is small, it still isn't solving the main issue. Realistically if you wanted decent power out of an Eaton on a rotary, you'd use an M112. As I stated earlier, sizing depends on your power goals. If you want 300+hp with an Eaton, it'll be at least an M112 in size. If you'd like the 250hp range, you can get away with the M90. The M62 will lose you power.
There are ways to get more out of an eaton blower. You can machine new rotors out of a lighter composite material and make the tolerances tighter. You can alter the inlets and outlets to have a nice shape good to airflow and then time them to a perfect 120 degrees of rotational opening. You can change the bearings to give you bearings that perform better at higher speeds. The throttlebody size on these is huge in making more power. Go up to an 80mm and power will go up. Design the intake duct from the tb to the blower for good flow velocity. These things can all add up but if the blower is small, it still isn't solving the main issue. Realistically if you wanted decent power out of an Eaton on a rotary, you'd use an M112. As I stated earlier, sizing depends on your power goals. If you want 300+hp with an Eaton, it'll be at least an M112 in size. If you'd like the 250hp range, you can get away with the M90. The M62 will lose you power.
02-28-2006, 10:28 PM
#2899
Registered
Actually I need to go back and think that one out again. I'll post again when I make sure I've got it straight.
Last edited by rotarygod; 02-28-2006 at 10:31 PM.