Rumble from the rear - when is too much?

[KKson]

Well the pops and bangs on the over run from my 350i are certainly quite spectacular at the moment but can too much be detrimental?

Bradderztvr has followed me a couple of times now and he says it's like a shot gun going off on occasions. There's certainly a fair few full-on back fires when all is warm and I'm using the engine for sharp deceleration. Also when I'm heading through some of the enclosed small villages around here the noise is most entertaining although some of the more mature residents do not appear to approve.

Question is - can all the popping and banging actually cause damage to the exhaust system or engine with the back pressure generated?

[ElvisWedgely]

a bit of popping and banging on deceleration on the flapper set up is fine, but shotgun sound is more likely to be sticking or burnt valves. At that extreme, in my opinion, it can't be doing the engine any favours.

Tony. TCB.

[mrzigazaga]

Its a TVR...They are meant to do that...Delilah was like an AK47 on full auto....My mates Cerbera sounds like a 40 gun salute and it spits flames!..

[GOG440]

They all do that sir.


Joking apart I have found that if I dont want the pops and bangs then stay in a higher gear than I would normally.

Apart from on the motorway when I cant (obviously) when I back off at 80ish I have made people st themselves with a nice loud bang next to them. I definitely havent ever done it on purpose to make people jump.

[smash]

If you've got air going into the exhaust system via a leak you'll get extra pops and bangs for sure.

[V8 Fettler]

There's a valve thingy on the plenum that might need fettling. See vintagemodelairplane

Edit: go and find some tunnels before fettling

[Trickie Dickie]

IT CAN NEVER BE TOO MUCH!!!!! - IMHO

Trickie

[ElvisWedgely]

Mine is a 3.9 hotwire with the big valve cylinder heads. There is no popping or banging at all. Decelerating or accelerating. What it does have though, is plenty of power and torque, endless revs, and a very loud exhaust note.

Tony. TCB.

[KKson]

Thanks for the various replies. I've pulled a couple of plugs out and the mixture looks fine and there's no leakage on the exhaust so I'm assuming it's just a particularly noisy 350i. As Ziga described Delilah, it does indeed sound like an AK47 on full chat. Unless the exhaust is blown apart by one of its more flamboyant back fires I'll assume it's meant to be like that! Cheers.