RobT 394

M&M side delete for me. Zero drone. Not as loud as bypass unless you are on the throttle. Less weight and heat compared to by pass. Some manufacturers allow you to keep valves, that helps with low end.

As for cracking the center muffler, that depends on how you drive the car. When I was tracking the car with side delete I cracked them all. Stock, M&M, and a Titanium one. For track, bypass with no sides is still the best for me as nothing breaks! And there is not much too break. On street I have never cracked a rear muffler.

Keep in mind the Cups come with no sides and a center muffler. That muffler is strong, I have never cracked the cup muffler on my 2013 Cup. Makes sense to me to put the same setup on the street car.

joejenie

Question on these exhausts and emissions? I'm in AZ and live where you have to do emissions tests every 2 years. It's a OBD test IIRC and not a sniff test, but my question is on the Dundon full exhaust. Thinking about doing the full system on my 997.2 GT3RS including no cats. Will it pass inspection as long as there is no sniff test? Or am I dreaming and need to do a Catted system (which Jamie at Dundon says don't work well yet and they are working on it)?

rnh204

If all they do is plug in the DME to check the ready status monitor and your state accepts 4 out of 5 monitors being in ready status, you'll pass. That is how NY state is.

joejenie

I guess I need to figure out what the state will accept here. Moved here 5 years ago and have never had any cars until recently that were old enough to get a emissions test (first 5 years of a car don't need to be tested).

D-Uber Cars

Charles Dundon of DMS has provided me with complete full exhaust for my 996 GT3 and current 997.1 RS, uncatted version. WA state emissions are via OBDII. No CEL's, no issues and has passed without incident. Highly satisfied.

Rick-A-Shay

In CA, if they look under the car and suspect aftermarket non-state approved hardware (cats), game over, from what I understand. Otherwise, OBDII and end of conversation!!

boostedt0y

+1. When I last smogged my GT3 the tech looked through the wheel wells and under the car to confirm I had the stock cats on the car.

modoz61

Everything I read and hear of the Dundon solution - its great

I have tried far too many configurations in my hunt for the best of all worlds

I stepped straight out of stock into Akrapovic Evolution Race - Headers, Cats, Side deletes and rear centre. - Drone on road trips was a killer but sounded fantastic on track at WOT.

I tried an EVOMS system - I wasn't given the information about removing the cats for track days and had the cats collapse - if I'd had that information up front I wouldn't have bought the system - but its very well made and would be great for road based car or for those who like to spend time under the car for track days ( that's not me)

Before Dundon developed their system I tried another variant that I like - A lot! Akrapovic Header, TPC Racing side deletes with valves (I had to have the end coupling fittings modified) and Akrapovic rear. these side deletes are somewhat unique in that they connect to the upper and lower inlets of the rear centre exhaust. If using the standard car sport exhaust control have the valve open at under 3500 RPM - this provides gas flow to both upper and lower inlets this is quiet and no drone and you can hear phone conversations - I need to travel at least 90 minutes to my nearest track and we do some really long road trips that have sections of non-spirited driving where drone is annoying. I put a carnewal controller on this system which allows me to control the rear valves independent to RPM. Close to perfect for me.

I am doing an engine upgrade at the moment and moving to a MOTEC controller and I will be changing the function of the sport exhaust button - OFF - no light on switch normal RPM control, ON solid light on switch Valves open (quiet mode) - If its possible in MOTEC programming I would add a third operational mode On flashing light on switch and Valves closed (loud mode)

With some tracks over here now getting sensitive to db levels - you need to be careful and I like the Jekyll and Hyde nature of the system

If I was going around again I would seriously consider the Dundon system.