cinellipro

Hello just recently purchased a pair of muffler deletes and have read about Car Chemistry inserts to reduce drone. They sell 3 and 4 disks type with optional caps that are intended to eliminate some of the volume and most of the drone. I am okay with the loud muffler delete as my car is not a daily driver. Am looking for an "event" when I drive it just don't like the idea of drone. I'm not tracking the car so power loss not an issue.
Question is has anyone used the inserts and what has been your DRONE experience with the 3 or 4 inserts? Any recommendations?

Thanks
Cheers

1999 C2, roll bar, AASCO lightened flywheel, Function-First motor mounts, Poly bushings all around, H&R Roll bars, Racing Dynamics strut bars F&R, short-shift kit, front center console delete, rear seats removed.

cinellipro

This is what each insert looks like with 3 disks.

Slakker

FYI, with muffler and cat delete, my car was SO LOUD that the track asked me to put mufflers on of some kind because it was so annoying. And this was a rural track with no noise ordinance. It's unreal how loud these engines are naturally at WOT.

cinellipro

I had the 3-disk CC insert from Car Chemistry installed this morning. It’s about 7 inches in length and 2 ¼ width at each disk. The local muffler shop Caribe who performed my last muffler hack also did the muffler delete/insert job today. I kept the original catalysts in place and took home the mufflers as a just in case. The inserts slid in the pipe and welded in place. It took no more than 20 minutes to complete the job and the new shiny outlets look great (that’s all you see).

I started the car and noticed the volume and tone were significantly different than what I drove in with. So far I’ve driven the car about 10 miles and it still feels foreign. If it were someone else’s 996 the effect would not be so pronounced so it’s going to take a few drives to acclimate to the new sound and feel.
First the volume went up but not annoyingly with windows up or down. It’s drivable and the CDR-220 radio works fine at lower volume levels. At idle it sounds amazing and up the power band as well.

The tone went down a few octaves from the fister gundo hack-bypass set up I was using. It now emanates a very serious deep guttural burble type of sound. Quite a difference compared to the higher-pitch sound I was driving with before. What drone existed was completely acceptable and confined to 2200-2400rpms in any gear. I would not have gone this route if there were any risk of annoying drone. What sounded and felt as drone was not uncomfortable or noisy in the cabin and no other droning noticeable below and above that rpm range. I’ve read the 4-disk version eliminates the drone altogether, but it also restricts power. Someone will have to do a dyno reading on the three disk and the four disk versions.

Regarding any loss of power due to the insert restricting flow, I have not felt any but I it’s too early to tell as I’m still getting used to the change. Will report on that subjective observation at a later date.

cinellipro

Now that I’ve driven the car for a few weeks, just wanted to report about my experiences with the install. At idle it continues to sound amazing and deep. Start-up is an event. It sounds louder than the previous set up, but not uncomfortably loud. It’s not a daily driver so I’m comfortable with the db count. Up the RPM range it also sounds great, deeper, burbles and occasional crackles. The drone shows up as a minor inconvenience between 2200-2400RPMs. I can feel and hear the acceleration and deceleration of the motor and that is also cool.

One problem. It lost power. I have an AASCO lightweight flywheel and the acceleration and the free revving that was there is gone. Floor the gas pedal and it takes noticeably longer to move up the rev range. It’s disappointing.

I thought about the 2 disk version but if it means an increase in drone forget it. I kept my mufflers.
Not sure what I’m going to do.

dan_189

I ditched my Aasco flywheel, I thought I liked it but I wouldn't have it back.

If you're not happy you can always go back to stock or 100 or 200cel cats. Exhaust is one of the things that's easier to configure and swap parts in and out (headers, mufflers or cats).