I have often wondered about the helmholtz chamber on the 3.2 intake. It's basically an odd shaped divergent section. It's much different than an accumulator type appendage which is usually seen. Even an F1 exhaust system has this discrete volume arrangement; have a look at the 2.5 L intake chamber.
Perhaps it's just enough to give some positive effect
Sound wise I can't speculate as I now have a large 3.25" pipe and cayman TB....I have needed to stay at 3.00" to give any sort of feedback
Oh yeah this thing roars when you floor it on cam.....I feel like I am waking the dead!
Quote:
Originally Posted by Topless
Nice summary of the challenges in improving on the stock intake design Radium. From my rough calculation, a 2.5L 6cyl motor only requires a 2" ID intake to achieve max VE at redline so I don't have heartburn over the stock design. If I jumped to a 3.4L motor and exhaust I would certainly need to re-tune the intake. No well-tuned intake would be complete without a carefully placed helmholtz resonator to cancel the acoustic pressure wave that would otherwise certainly foul your MAF sensor readings. Bigger and smoother are just the tip of the iceberg in a performance-tuned intake design.
A useful resource for getting the math right:
Volumetric Efficiency (and the REAL factor: MASS AIRFLOW), by EPI Inc. |
Lil Red
2009 Porsche Cayman 2.9L
Hybrid Mode
