New 3” X pipe exhaust by Dr. Jekyll

3 minute(s) of a 36 minute read

I'm still loving this exhaust! Just had it out this morning getting some logs for EPL. They are retweaking my tune to take advantage of the much freer flowing exhaust and GT2RS intercoolers  Even at 1.2 bar this thing has traction problems. Next revision will be back up to 1.4-1.5 bar  A set of Toyo R888's might be in my future... 

I did get some interior dB levels today. Previously, part throttle cruising (2500-2600 rpm) was 103 dB in the interior with the windows up. With the changes to the exhaust it's now 91dB at the same rpm/speed. IIRC, every 3 dB's is doubling in volume, so this is a HUGE decrease in interior volume/drone.

5-18-2014

I think people confuse loudness with drone. Loudness of an exhaust can be controlled by a muffler. The number, type, and size of the mufflers can decrease the loudness (inside the cabin and outside of the car) of the exhaust. Adding large mufflers can also decrease the drone.

What I wanted was an exhaust that sounded aggressive, was pretty loud, but didn't have any drone (aka: the low frequency vibration that rattles things in the car... including your brain). Adding the helmholtz resonators eliminated the drone and then Chris was able to separately tune the loudness of the exhaust to exactly the sound that I wanted using the smallest sized mufflers that were necessary. Obviously the loudness/sound of the exhaust can be tweaked based on an owners preference. 

If you just use a muffler to eliminate drone, you end up with a massive, heavy system, that muffles the sound and reduces flow (stock exhaust). 

I'm still extremely happy with my setup. The wife and I took the car out to C&C in Richmond yesterday, which is about a 45 min, mostly highway, drive each way. Not a single complaint about drone despite keeping the rpms at 2400-2800 the entire time. My TBSS with stock exhaust draws more complaints than the Porsche. So trust me, she would let me know if there was drone