Ron--I agree with you also--somehow find how much restriction is caused via the Cat & match it with a baffle--however the fix also needs to eliminate the annoying noise--it's at one of those frequencies that really irritate. The noise isn't bad at 45 mph but getting to 70 mph & above--just cruising with freeway traffic--turn off the radio--can't hear it anyway & I could live without the radio but not that noise frequency.
I have the Stage 2 upgrade on a 2015 F3's. I initially tried the Cat Delete from one vendor with poor low end torque on the stock ECU. After the Stage 2 upgrade many had stated their performance was great. It's been very hot mid 90's degrees thus it may not be totally fair, But my 2015 F3's has better torque off the line with the Cat installed. BTW I've read several people state the Cat weighs 30 lbs. Mine weighs 17 lbs.
The absolute worst part of the Cat Delete is the noise on the freeway at 75-80 mph. I could not tolerate a long drive with this obnoxious blaring in my right ear. Couldn't even hear my audio system. I have the Chrome Akrapovic Straight Shot Muffler .
On the positive side I had 2 different style spring hooks--the wire based spring hook from Doc at Roadster Restorations is the Best. The straight bar hook is not good for the two harder to reach springs. Also a suggestion from "ZUMI" to tie a strap to the spring hook & use the leg for strength in stretching the spring was Excellent.
I ran this Cat delete pipe without any baffle. Now I have my 2nd Cat Delete pipe up for sale for $165 including shipping to 48 states. This Cat delete pipe has 50 miles on it-thus almost new & comes with the bar type spring hook & a baffle that has two opening options.
I was wondering about droning sounds. I see that to OP is using a Akra exhaust. I was/am considering the cat delete with my OEM muffler. Can you share details with your cat delete pipe thru a PM ? Thx
How does it run?..with the cat back on with the stage II and the straight shot pipe?...as in take off?
Unbelievable the different results from the similar setup....... Also on the fumes--something may be wrong or a extremely sensitive nose. I never smelled any difference while idling & above 20 mph the Spyder would be out of range before the exhaust emitted. Maybe my nose has gone the direction of my eyesight:dontknow: Darrell
The resonator on the RLS makes a big difference..Are you running lamonster cat delete or RLS there is a big difference.As for the smell i checked that there is no leaks on the joints and as soon as i put the cat back smell is gone. Some people love the smell and may not notice its there or you may have a good full face helmet.
This is true per Federal emissions law. If you live in an area that does annual emissions testing, easy enough to swap around.