Ok, so working on this car been a bit of slog lately. The process of replacing the radiator hoses led to a problem with the distributor which led to a problem with the injector harness.

But finally got it all sorted and decided to take the car for a drive.

Getting on the highway, I hit a small bump which immediately resulted in a distinctly “throaty roar” when I mashed down the accelerator. Quickly exited and returned home driving cautiously the whole way.

The root cause wasn’t too hard to determine...



I think I see the problem!

I had been contemplating removing at some future date the forward silencer using a kit from Simply Performance. But the way it sounded with the second silencer hanging down was not at all pleasant, especially with the top down.


The forward silencer in question

I would eventually like to remove or gut the cats, but not ready to tackle that at this time.

Does anyone have experience modifying the exhaust on a convertible to advise how it sounds? Any recommendations?

 

Sorry, what I thought was the forward silencer is actually the intermediate catalyst.

So can I eliminate half of the cat restriction by simply getting a longer intermediate pipe?

Still curious if anyone has experience eliminating the first silencer and how it sounds.

Thanks

 

Removing the junk mufflers under there ad gutting your cats if applicable will give it a nice growl without the lawn mower-ness. You will also see the fastest HP gains with an unrestricted exhaust and if cats are fitted and then gutted your fire potential goes way down.

I've been fiddling with my car's exhaust for YEARS - could probably of bought the kit with all my tinkering repair bills but I've more or less got it sorted with X pipe to high-flow mufflers to side exits with resonator tips.

I believe all things considered you'll want to keep the rear resonator and pipe assembly they work better than exhaust tips.

 

Just something that caught my eye in this. That covered wire hanging down I think is the rear CPS cable... It can and will come into contact with the very hot area just after the down pipe, melt the insulation and short... The slack can be pulled up from the top and zipped to the cross pipe, and below the cable/wire and covering can then be zip tied away from the pipe to a small hole, I'm guessing designed for this purpose, in the area of the inspection cover at the bottom of the bell housing.

 

Well spotted that will snag or hit something hot and lights out for the engine!

 

I had a Series III V12 sedan and I bought the European downpipes that do not have catalytic converters and removed all my cats. I didn't do any before and after 0-60 times, but the seat of the pants meter said that removing the cats made zero difference to the performance or fuel economy.

As far as I could tell, it was an expensive way to achieve nothing, so I would leave the cats in place unless they are actually damaged or plugged.

 

Greetings


found this on u tube .... enjoy ....!

 

Euro downpipes, no cats, center box delete from Simply Performance, rear mufflers thereby is all I have.
Deep rumble in idle, no real noise until you reach 3000 RPM. I like them for leisure driving, but the drone at 3000-3500 RPM is annoying on motorway as it exactly where both me and the car like to be...

Youtube