Splitter causing shuddering.
05-21-2014, 03:32 PM
#31
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Okay, so what does a 944 non-turbo get for a splitter? Are there any race quality choices? Is the old A.I.R. setup with turbo-look front bumper cover and splitter still available? I submitted a query on the old website with no response.
http://www.americaninternationalraci...259246&page=74
edit: I heard back. It is still available.
http://www.americaninternationalraci...259246&page=74
edit: I heard back. It is still available.
Last edited by rlets; 05-21-2014 at 05:47 PM.
06-19-2014, 07:10 PM
#34
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06-20-2014, 02:24 AM
#35
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Damn, the thing still shudders.
At the same speed.... it's a bit less violent, but still there.
Will try some body molding tape, and see how that goes. I think the air pressure is high enough, that it squeezes between the valance and splitter, causing a slapping effect.
About the rods..... I found most of the materials in the scrap metal bin at my work.
The top of the rod is attached to the aluminum bumper with an eye bolt, and the bottom has an aluminum U shaped bracket, that I bent myself. It's held on to the splitter with a countersunk screw.
http://www.ebay.ca/sch/i.html?_odkw=...nkage&_sacat=0
Looks like e-bay has a few things that would work.
At the same speed.... it's a bit less violent, but still there.
Will try some body molding tape, and see how that goes. I think the air pressure is high enough, that it squeezes between the valance and splitter, causing a slapping effect.
About the rods..... I found most of the materials in the scrap metal bin at my work.
The top of the rod is attached to the aluminum bumper with an eye bolt, and the bottom has an aluminum U shaped bracket, that I bent myself. It's held on to the splitter with a countersunk screw.
http://www.ebay.ca/sch/i.html?_odkw=...nkage&_sacat=0
Looks like e-bay has a few things that would work.
06-20-2014, 09:09 PM
#36
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Damn, the thing still shudders.
At the same speed.... it's a bit less violent, but still there.
Will try some body molding tape, and see how that goes. I think the air pressure is high enough, that it squeezes between the valance and splitter, causing a slapping effect.
About the rods..... I found most of the materials in the scrap metal bin at my work.
The top of the rod is attached to the aluminum bumper with an eye bolt, and the bottom has an aluminum U shaped bracket, that I bent myself. It's held on to the splitter with a countersunk screw.
Looks like e-bay has a few things that would work.
At the same speed.... it's a bit less violent, but still there.
Will try some body molding tape, and see how that goes. I think the air pressure is high enough, that it squeezes between the valance and splitter, causing a slapping effect.
About the rods..... I found most of the materials in the scrap metal bin at my work.
The top of the rod is attached to the aluminum bumper with an eye bolt, and the bottom has an aluminum U shaped bracket, that I bent myself. It's held on to the splitter with a countersunk screw.
Looks like e-bay has a few things that would work.
06-20-2014, 09:35 PM
#37
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https://lh6.googleusercontent.com/-V...nter%25201.jpg
Do have a centre mount, but it might not be enough.
Do have a centre mount, but it might not be enough.
06-21-2014, 12:08 AM
#38
Burning Brakes
The shudder may be flutter, an aerodynamic force which can come on suddenly and catastrophically at a given speed. By suddenly, I mean in less than 1/100th of a second, per NACA research about 75 years ago.
Having the mass forward of the center of pressure helps a lot, hence weighted ailerons and horizontal stabs on aircraft.
Having the mass forward of the center of pressure helps a lot, hence weighted ailerons and horizontal stabs on aircraft.
06-21-2014, 04:11 AM
#40
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A nice sheet of aluminum in the shape of the splitter and the airdam fitted underneath may solve this. If that lip is "hollow" behind it...meaning that the air once it goes below the lip can suddenly travel vertically to fill the void behind the splitter/airdam/fasia then you need to stop the air from getting UP and behind the splitter.
I have built my own splitters on my Datsun, and made a large single piece aluminum belly pan that extended from the splitter/lip all the way back to my transmission/firewall. The belly pan is THE lowest part of the splitter/airdam. It kept the air meant to travel under the splitter, to stay close to the ground. Aerodynamics is a funny(weird) and potentially dangerous thing.
Be safe.
I have built my own splitters on my Datsun, and made a large single piece aluminum belly pan that extended from the splitter/lip all the way back to my transmission/firewall. The belly pan is THE lowest part of the splitter/airdam. It kept the air meant to travel under the splitter, to stay close to the ground. Aerodynamics is a funny(weird) and potentially dangerous thing.
Be safe.
06-22-2014, 03:30 AM
#41
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https://lh6.googleusercontent.com/-V...nter%25201.jpg
Do have a centre mount, but it might not be enough.
Do have a centre mount, but it might not be enough.
06-24-2014, 09:47 PM
#42
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There is absolutely no shudder below 90 MPH.
I wouldn't drive around with it on if there was, and It's more than just a "for looks" add on.... at least it will be when I figure it all out.
Oh, no, I do not, and I should..... maybe 2 more rods evenly spaced out.
Yes, it is hollow behind the lip area, thus there being no weight in the front, and letting air travel up under it. Something like what Tony G has done, would deffinitely solve the problem.
A piece of aluminum that big would be pretty heavy, despite it being aluminum.... how thick was the one you used, Zr8ed?
So... why are there, no issues with the Mantissport S2 splitter? It's a bit different than the one for the NA nose, but pretty close. That would imply it's a mounting issue. Once i'm satisfied with the mounting, if it still flutters..... than i'll move on to structural improvements...... Or as CHICKS would do... remove it.
06-25-2014, 03:02 AM
#43
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You could go with fairly thin aluminum.
Here is a (crappy)cross section drawing of how I think it could look. You would use the support rod mounts to attach the aluminum belly pan to the bottom of the splitter. The original belly pan mounting points could be used to attach the rear of the new aluminum belly pan.
Here is a (crappy)cross section drawing of how I think it could look. You would use the support rod mounts to attach the aluminum belly pan to the bottom of the splitter. The original belly pan mounting points could be used to attach the rear of the new aluminum belly pan.
06-25-2014, 07:37 AM
#44
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Yes, it is hollow behind the lip area, thus there being no weight in the front, and letting air travel up under it. Something like what Tony G has done, would deffinitely solve the problem.
A piece of aluminum that big would be pretty heavy, despite it being aluminum.... how thick was the one you used, Zr8ed?
A piece of aluminum that big would be pretty heavy, despite it being aluminum.... how thick was the one you used, Zr8ed?
Hope this pic works
The cutout is for my oil pan.