COLD AIR INTAKE NEXT LEVEL OF PERFORMANCE?
#181
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I doubt that very much. Helmholtz (not heimholtz) resonance requires the derivative of the free air space to be a functional multiple of the speed of the air passing(for non-stringed cavities) a flange or curve.
The best and simplest example is to blow perpendicular to the volute of a Coke bottle, just at the aperture. This sound is a Helmholtz resonance.
The intake geometry of the 928 doesn't provide any derivative which comes close to the free air speed of the intake air movement. Maybe it would at air volumes when running around 10,000RPM or above, but anything under that, you won't get any resonance unless there are some straight lines with flanges in the 928 intake I'm unaware of.
The best and simplest example is to blow perpendicular to the volute of a Coke bottle, just at the aperture. This sound is a Helmholtz resonance.
The intake geometry of the 928 doesn't provide any derivative which comes close to the free air speed of the intake air movement. Maybe it would at air volumes when running around 10,000RPM or above, but anything under that, you won't get any resonance unless there are some straight lines with flanges in the 928 intake I'm unaware of.
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#182
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ABS plastic 4 inch ABS 45,90 degree elbows,straights,T,Y.
The 4inch rubber connectors have grooves in them for the clamps.
Haven't tried any,ABS material there are some parts that probably would fit.
Some links where I have seen the parts are below.
These were the 4 inch parts,maybe Roger can try some out to bring the cost down more on the cold air intakes.
http://www.woodcraft.com/Family/2000...-Fittings.aspx
There are also a couple elbows at harbor freight.
http://www.harborfreight.com/4-inch-...bow-97498.html
http://www.harborfreight.com/4-inch-...tor-97499.html
The 4inch rubber connectors have grooves in them for the clamps.
Haven't tried any,ABS material there are some parts that probably would fit.
Some links where I have seen the parts are below.
These were the 4 inch parts,maybe Roger can try some out to bring the cost down more on the cold air intakes.
http://www.woodcraft.com/Family/2000...-Fittings.aspx
There are also a couple elbows at harbor freight.
http://www.harborfreight.com/4-inch-...bow-97498.html
http://www.harborfreight.com/4-inch-...tor-97499.html
Last edited by inactiveuser1; 05-06-2013 at 12:24 AM.
#183
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I May be able to use the elbows by extending the length of the ducts on the Y section. The current elbows are 5 x that price. However as most customers want a polished or powdercoated finish the plastic does not help that much.
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Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission?
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Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission?
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928 Owners are ".....a secret sect of quietly assured Porsche pragmatists who in near anonymity appreciate the prodigious, easy going prowess of the 928."
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The pictures of the ABS parts are for those who may want to try them out for a regular cold air intake.
These were the 4 inch parts.
http://www.woodcraft.com/Family/2000...-Fittings.aspx
There are also a couple elbows at harbor freight.
http://www.harborfreight.com/4-inch-...bow-97498.html
http://www.harborfreight.com/4-inch-...tor-97499.html
Last edited by inactiveuser1; 01-06-2012 at 03:11 PM.
#187
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Nice to see this thread bumped. I didn't realize they made those elbows in ABS plastic other than for PVC applications ala Home Depot and Lowes.
With the price of those elbows, the cost for me to build one is now 30% of what it was before. I have also found clear acrylic tubing to use for visible filters.
With the price of those elbows, the cost for me to build one is now 30% of what it was before. I have also found clear acrylic tubing to use for visible filters.
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Quit on the project awhile back and started back on it some.Have some different motors that are larger.
Drilled the housing for the grommets for wires.Waiting for maching shop to start on adapters to mount the larger motors to the housings.
I want to at least get the housing done.Then have to design adapters from the motor shafts to blades.
Its one of those projects where you wish you didn't start it but want to someday finish.
Hopefully I still have the car by the time I finish this or it will have to go on something else.
I don't look at it as an electric supercharger more like hopefully the best cold air intake for the car.
Project still has a long ways to go.
Drilled the housing for the grommets for wires.Waiting for maching shop to start on adapters to mount the larger motors to the housings.
I want to at least get the housing done.Then have to design adapters from the motor shafts to blades.
Its one of those projects where you wish you didn't start it but want to someday finish.
Hopefully I still have the car by the time I finish this or it will have to go on something else.
I don't look at it as an electric supercharger more like hopefully the best cold air intake for the car.
Project still has a long ways to go.
Last edited by inactiveuser1; 05-06-2013 at 12:28 AM.
#191
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