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Loudspeaker port + square hole at the start.
Figure this one out.
Note: this guy is awesome.
Why?
Here are the measurements for his port:
http://www.svtperformance.com/forums...s-numbers.html
Found a few threads on SVTP: posi or steig.
posi was the answer.
Looking at our casting I can see the area of which was removed.
The area which does not seal with the rotors.
Going to look into this further.
Might not be able to replicate fully due to significantly shorter rotors.
Possibly something similar to this:
http://www.posiperformance.com/gt500-race-port
We have to remember that the air goes around the outside of the case, not directly down through the middle of the rotors. So when the rotors are being spun, all the air is being pushed to the back (snout side) of the case. Therefore there would probably be very little air trying to go through the bottom of the case where people are saying we should cut out, or basically right in front of the bearings. This is also why i believe part of ZZP's design to be good. You see, the back (snout side) of the case is not flush with outlet. The air gets pushed to the wall and then down and over the lip (bottom of the triangle). I believe this is where most of the improvements come from. Reducing the size of the lip (you cant remove it all because its part of the case that bolts to the snout) and cutting into the bolt hole things (cant think of the word) should reduce restriction and improve flow.
Have detailed photographs of a modern ZZP outlet?
This isn't exactly a detailed photograph.
However if this is the best thing going I guess I should leave my outlet alone because thats what I've done.
Im not trying to stop people from trying new things, I'm just giving my opinions and adding suggestions on where our efforts could be applied. And I think the only reason its not a full triangle opened up all the way to the bottom is that the bolts need a little material to screw into. If structure wasnt an issue I would pretty much just cut the whole bottom of the triangle off the case.
Oh the bottom isn't what I'm concerned with. its extending upwards.
On my blower I've removed the bolt bosses, then beveled the outlet, nothing else.
gen III's are cheap enough to buy another case and try the loudspeaker outlet...![]()
I know our blowers do not compress air inside, but they are pushing more air into the LIM then is being used... this is causing an increase in pressure and a squeeze. Since the blower and more specifically the rotors are the source of the increase in pressure, i would expect the greatest pressure would be at the rotors. to reduce heat we want that pressurized air out of the blower as quickly as possible. as with head porting you want velocity and volume. if we just cut the bottom of the blower out we will loose velocity and not move the air. [yes i am going somewhere with all this] wait for it..... my theory is if we open a small slit about .5 to 3/4" wide at the top of the triangle and carry it almost all the way to the top (where the bearings are) ending in a .25 to .5" wide slit, we can allow more air to escape before it gets squashed by the rotors going back up.
I have 2 M90's and seeing as how busy i have been with work... it will be a while until i can finish my topswap... so i have time to port both blowers and give them a shot.
on a side note... i remember seeing years ago a product that will seal aluminum... it wasnt a polish so it wont eat away the case, but if it builds up the surface of the SC it might help increase efficiency! just another idea to throw out there in the attempt to rebuild the wheel.
i'd also like to look into getting a non contact thermometer and check the temp of the case... if above 150* it might help to create a water jacket around the blower to cool its surface... it wont be major but could be an interesting side project too... could incorperate this into a SC oil cooler too.
If you have two case I would leave one stock and implement your idea on the other one.
I am in no way shape or form trying to say that i am an expert on these engines or superchargers, but i see alot of guys talking about boost this and boost that.. Yes boost is good.. But cfm is what its about. Boost is just the measure of restriction of the compressed air entering the engine. Isnt it better on everything if you can port the charger, lower intake manifold and the heads and get MORE CFM (more air flow) with less boost?! I mean you wont be working the SC or turbo near as hard and getting the airflow you want. Best of both worlds. Just my .02 i have picked up for my high performance diesel experience
Last edited by Jackblack99; 02-10-2012 at 12:56 PM. Reason: Info
If the engine needs to see 500 CFM to see 10 PSI of manifold pressure, and your alter your blower, but leave the rest of the engine exactly the same, it stands to reason that an increase of volumetric efficiency would result in increased manifold pressure, and vice versa.
My blower case after a quick ten minute drive with a couple wot runs ended up around 150-160* F
Heres some results from the same day going from GM supercharger fluid to mobil 0w-20. Never did see a significant difference.
ECT 199 197 snout 171 165 case 160 150 core 147 IC in 127 108 IC out 131 115 FMHE 125 Ambient 89 85
Last edited by matt5112; 02-10-2012 at 01:37 PM.
Lets just say that the blower or turbo flows 800cfm at 15-17psi and its at the peak of its effeciency and its screaming... Doesnt it make sense to remove some restriction (port work on heads, lim, blower housing...etc) and get the charger to put out 800cfm at 11-13psi of boost. You have the same amount of air going into the engine, but you have taken se stress off the charger cause your not pushing it to the limit. Im just saying since i have been around turbo or supercharged performance i always see people talk about how much boost their car or truck makes.. But no one ever talks about the cfm or #'s per min of air they have. You can make 100# pf boost if you want.. Buy if your only flowing 3-400cfm of air at 100 psi.. Then my 5-700cfm at 40-50 psi will make more power and have less failure.
Given the engine air requirements are not changing in the scenario i'm suggesting and the blower drive ratio is not changing, if there is less pressure in the manifold, the blower is moving less air.
I understand your point, but for a valid conclusion we must only change one variable at a time.
Now it appears ZZP already went through this with their s/c "dyno" (more accurately it should be called a flow bench) and found the stock outlet to be the "best", but without seeing their results, who knows what their perception of "best" is.
Perhaps we could ask zoom?
MORE ON OUR VENOM COOLERS - Supercharger Q&A, Moderated by Dyno Bob
Like this? I'm having Stiegemeier do this to my supercharger. I don't believe he's done any for the GP M90 yet but he has a couple different designs. He says it cuts case temps by 50% or an observed 100 deg difference in case temps when used with an intercooler. I'm going to have a stand alone system for cooling this so I'll just be cooling the case, should work well with my E85 build.
You have the correct concept. I've built my own flowbench and tested lots o' Eatons on it but never flowed an M90. But the concept and #'s are apllicable from the designs we did test. The testing shows that balanced porting of the inlet and outlet is critical. Improving the efficiancy of the supercharger also aided in IAT temp reduction and an increase of boost by 1 lb at 14k blower RPM.
N/A intakes function in a % of atmospheric efficiancy. Very few hit 100% ( when measured at 1 atmosphere or 28" of water) but some will actually exceed 100% ( let assume a tunnel ram design) . Assume the Eaton is just an intake manifold. If you view the rotor as a "valve" filling the flute of the rotor with air as it rotates in the case it actually becomes more difficult to fill that valve area. But its also a finite area. That's why a small blower like ours runs out on top, along with heating the air and making it less dense. So a good port design will efficiantly fill the rotor area and efficiantly exit it too. The way these rotors and cases are designed with moving air in that valve area too large an exit and entrance can essentially create "overlap" where the "intake" and "exhaust" of the inlet and outlet side of the rotor are open to each other.
Didnt you make that supercharger dyno? I bet the OP would like to use that.
Yes, I built Stiegemeiers supercharger dyno and he could send it in and have it dyno tested if he would like. I'm not sure what Stiege would charge but if he wanted a comparison vs a stocker we could do that also. I would also put mine on there (Stiege's design) and see how the three compared. To test a supercharger we usually make at least 3 full runs and compare data.
Also, I lied when I said I never tested an M90, he's done quite a few Saleen and Roush blowers on it.
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