Backbox delete yes or no?

[tonyg1987]

Has anyone had their backboxes removed/deleted? Apart from noise increase and weight saving is it good for turbo cars?

Has anyone with a E63 or CLS done this before?

 

[kianok]

Surely if you do that you’ll get pulled more times than a Swedish handyman.

 

[jamiet1986]

Had this on my 55, drones badddd

 

[Flyinspanner]

When I bought mine, the backboxes had been deleted. It was fun on start up, but the abysmal droning in real world driving 1500- 2500 rpm made one of my first jobs sourcing a replacement pair.

 

[JDL60]

Had it in an SL500 quite loud! Wasn’t terribly bad

 

[Cozy]

An acquaintance did this on his W205 C63 and he reported that the car ran like crap. I was struggling to understand why, but then realised that the rear boxes are valved so perhaps the ECU was looking for them, yet couldn’t get an electronic or vacuum signal, consequently causing it to pull something back. I don’t have all of the facts but I wouldn’t expect the ECU to pull timing because of this, and generally removing any restriction on a turbocharged engine is beneficial and not subject to the same science as NA.

Maybe do some research into this if the E63 is similar.

 

[tonyg1987]

An acquaintance did this on his W205 C63 and he reported that the car ran like crap. I was struggling to understand why, but then realised that the rear boxes are valved so perhaps the ECU was looking for them, yet couldn’t get an electronic or vacuum signal, consequently causing it to pull something back. I don’t have all of the facts but I wouldn’t expect the ECU to pull timing because of this, and generally removing any restriction on a turbocharged engine is beneficial and not subject to the same science as NA.

Maybe do some research into this if the E63 is similar.

That’s interesting as like you say, its not supposed to have any adverse impact if its turbocharged. It plays a part in N/A as they need to scavenge a certain amount from what I’ve read and something to do with the exhaust gas pulses but for turbocharged it isnt suppose to?

am going to stick with turbo downpipes and remap for now and see what happens next.

 

[AMGeed]

Daveenty had Weistec down pipes, secondary cats and resonator removed on his 5.5 biturbo and it was very loud!
Alps put the resonator back when he bought it to calm it down a bit

I wouldn't dream of removing the back boxes on the Biturbo.

 

[Doc matt]

Lol. Wait till your cats come out and trust me you’ll want to keep the standard box. I think this setup is perfect. In manual mode giving it some beans it’s loud as anything and when the wife is in the car and in comfort mode going out for the day it’s lovely and quiet.

 

[daveenty]

Daveenty had Weistec down pipes, secondary cats and resonator removed on his 5.5 biturbo and it was very loud!
Alps put the resonator back when he bought it to calm it down a bit

It was actually close to this but there were no secondary cats on mine, just the one per side so in effect it ended up with nothing. Once the cats were removed to fit the downpipes it was LOUD. If you're fitting full downpipes like the Weistec ones, the bonus is that you also lose the restrictive OEM front pipes which are designed for fit over function, thereby opening the system up and really helping the gasses flow.

I would not have removed the back boxes, it would have made it very uncomfortable under 95% of conditions. Coupled with the inevitable drone you'd end up with, you'd be spoiling a good car in my opinion.

 

[Cyclone1]

Brilliant advice above.

I’ve had just a resonator delete - sounds great

Then had Cats gutted and sounded incredible, at first I thought too loud, but soon got used to it. Plus it released another 100lb/ft of torque

Then I had downpipes fitted with the turbo upgrade. Didn’t notice a huge difference in sound except to say it still sounds incredible....

All work done by Torqueflow and MSL