TXshaggy

I have the Soul OAPs and stock PSE…perfect for me w/ no drone.

Many have reported drone with valves forced open.

Most get controllers to force open all the time…doesn’t sound that’s for you.

Larry Cable

The "drone" occurs when the valves are open ... So I don't think a controller is going to help with that ...

Keep the OEM PSE or replace the straight thru OAP and install a new exhaust system downstream...

I'm replacing my soul OAP with car graphic and retaining the akrapovic exhaust

UncleDude

I am looking forward to the results of your experiment Larry, AFAIK you’re the only one trying this combo.

TRZ06

Keeping the OEM PSE in place I believe is a requirement for those that are sensitive or do not want drone. For what ever reason, whether the motor design, piping route, etc. the 718 inherently drones in the lower RPM range. You need the values closed in those ranges to keep the drone at bay.

Bob Z.

Or disconnect the sound symposer: https://rennlist.com/forums/718-gts-...er-delete.html

tdlondon

Larry, for me the drone is worse with valves closed. At least more noticeable. Have Fabspeed OAP and resonated valved exhaust. Maybe it's because with valves open, the loudness of the growl offsets the drone

Soul Performance

We've found there is a significant amount of drone caused by the Sound Symposer on this car, which is further amplified by the resonant frequencies of various exhaust upgrades. We would recommend you take a browse at the Sound Symposer Delete thread we posted (link below) and remove that vibrating diaphragm assembly that is literally piping drone into the cabin behind your seats. It should make a very noticeable improvement in drone reduction as it has for everyone else so far on any exhaust configuration

SOUL Sound Symposer Delete Thread

Regards,
John Gaydos

NiteCrawlr

Same. I only notice unpleasant sounds in the lower rev ranges with valves closed. With valves open I hear the exhaust in those rev ranges which is quite nice. I have Kline exhaust and oap.

Larry Cable

working on it - I was thinking I would do a before/after video to demonstrate the change in sound between a straight thru pipe and the CG resonated/flow optimized OAP.

Alpha Ice

I have a JCR Manifold that is arriving in a few days. I'm going to meet up with a fellow GT4 owner and see how it sounds installed on a stock OAP and PSE setup. I'll bring my DLSR and Rode Micro to get some good exhaust sounds on it. I won't have my car for a few more months, but thought it would be good to check it out earlier and hopefully give some folks some more ideas for sound comparisons. We'll be starting at the wrong end, but I'm excited for the sound bump and check out the interior noise improvements.

Larry Cable

Shawn Hong

Soul street headers + soul race exhaust + sound symposer delete = AMAZING

pitt911

Hi John
are you guys selling the kit
I have your racing exhaust and I can appreciate less drone

mprog

I’m super interested in the kit too !

Shawn Hong

i have extra parts if you’re interested. I have soul street headers, soul race exhaust and it’s amazing after removed