Finally: Dyno charts of de-snorked 986S!!!

[porsche986spyder]

I wonder if the shape of the snorkle tube being a long smooth part leading up to the intake had some type of airflow/aerodynamics pupose. Therefore it would have been better to test it on the dyno with a fan blowing on the intake vent to simulate the car moving forward, since it was sitting still when you did the before and after test. Just a thought to consider for future testing.

[Bavarian Motorist]

http://www.ppbb.com/boards/ppbbphp/showflat.php?Cat=&Board=ARCHIVES&Number=820409&Forum=ARCHIVES&Words=10min&Match=Entire



Here is a good guide on how to remove the snorkel.



So removing this little thing will really make that much of a difference. Nice.



EDIT: For you, porsche986spyder

[porsche986spyder]

Originally Posted by Bavarian Motorist

http://www.ppbb.com/boards/ppbbphp/showflat.php?Cat=&Board=ARCHIVES&Number=820409&Forum=ARCHIVES&Words=10min&Match=Entire



Here is a good guide on how to remove the snorkel.



So removing this little thing will really make that much of a difference. Nice.



EDIT: For you, porsche986spyder

Thanks man!

[Bisimoto]

Originally Posted by porsche986spyder

I wonder if the shape of the snorkle tube being a long smooth part leading up to the intake had some type of airflow/aerodynamics pupose. Therefore it would have been better to test it on the dyno with a fan blowing on the intake vent to simulate the car moving forward, since it was sitting still when you did the before and after test. Just a thought to consider for future testing.

I did use a fan in 2 areas: the front for the heat exhanger/radiator, and the rear driver's side vent, but only to provide cool air. A single cylinder in our P-car engines demands air at 2000RPMs that none of my industrial grade fans can generate. As a matter of fact, a NACA duct (superior to our Porsche side vents) is only efficient as a ram at above 200mph.

2 weeks ago i performed a test using a fully radiused intake pipe on single cylinder induction tubes, and gained 12whp on a 320whp engine. Infusing such technology in our induction may prove benefitial, but the factory ram tube, incorporated with the "deflection cup" is a restriction, and hence, the power gains seen in the upper RPM range.

Thanks for the suggestion...great minds think alike!

[porsche986spyder]

Originally Posted by Bisimoto

I did use a fan in 2 areas: the front for the heat exhanger/radiator, and the rear driver's side vent, but only to provide cool air. A single cylinder in our P-car engines demands air at 2000RPMs that none of my industrial grade fans can generate. As a matter of fact, a NACA duct (superior to our Porsche side vents) is only efficient as a ram at above 200mph.

2 weeks ago i performed a test using a fully radiused intake pipe on single cylinder induction tubes, and gained 12whp on a 320whp engine. Infusing such technology in our induction may prove benefitial, but the factory ram tube, incorporated with the "deflection cup" is a restriction, and hence, the power gains seen in the upper RPM range.

Thanks for the suggestion...great minds think alike!

Wow! Thant's amazing. Thanks for all the info. Sounds like you know what your doing for sure. Please keep us posted with any more dyno test you do with other mods.

[porsche986spyder]

So what is your opinion of these "Ram" air vent ducts? I've seen 2 designs and was thinking of buying them before I de-snorkle my car. Any thoughts as to if these would realy work/help any more?

[Porschekid]

This is much appreciated Bisimoto! I hope you can get us a few mod dynos in the future as well.

[Bavarian Motorist]

I am going to do this on the week end and remove both the restrictor plate and snorkel.


I'll report back w/ some test results.

[MNBoxster]

Originally Posted by Bisimoto

I did use a fan in 2 areas: the front for the heat exhanger/radiator, and the rear driver's side vent, but only to provide cool air. A single cylinder in our P-car engines demands air at 2000RPMs that none of my industrial grade fans can generate. As a matter of fact, a NACA duct (superior to our Porsche side vents) is only efficient as a ram at above 200mph.

2 weeks ago i performed a test using a fully radiused intake pipe on single cylinder induction tubes, and gained 12whp on a 320whp engine. Infusing such technology in our induction may prove benefitial, but the factory ram tube, incorporated with the "deflection cup" is a restriction, and hence, the power gains seen in the upper RPM range.

Thanks for the suggestion...great minds think alike!

Hi,

As someone who did their thesis on NACA duct research, I can tell you that you are somewhat correct so far as Ram Effect is concerned. In fact, a Ram Effect is not achieved within a NACA Duct until transonic speeds are reached (about 0.8 mach, or approx. 609 MPH).

But, this isn't why NACA ducts came into widspread use in motorsports. It was because of a reduction in drag over previously used protruding intakes. This reduction in drag, not achieving a Ram effect, is what made them desireable...

Happy Motoring!... Jim'99