Hi, has anyone in here fitted or has their exhaust modified into a straight though pipe to nice tips at the end on a rrs 2.7 v6?
Tempted to get mine done but don't want it to sound like a boy racer car but something with more beef? Any feed back welcomed thanks
 
I've only heard a 4.4 V8 petrol with the rear box removed which is loud.
I'm not sure if you have cats on a Diesel or whether the exhausts boxes are required for back pressure on a Diesel but you could talk to one of the specialist exhaust manufacturers,there are a couple on eBay that advertise, and see what they say.
There are bypass valves that can be fitted but a straight pipe may sound nice briefly but would probably get annoying on a run.
 
As above. Exhaust design is quite an art and just removing restrictions can reduce torque output.
When it comes to antisocial exhaust noise levels - responding to compaints, the police can choose between the road traffic act and the police reform act.
 
As a mere yoof I had a BMw 323 shark nose with an aftermarket back box( twas a black one, the zorst that is) and it sounded the dogs danglies with the straight six.
Plod stopped me (cos they were jealous, obviously, and had questions ready about stuff like Insurance/tax/affordability lol), they commented on exhaust note, I simply said to them how much paperwork is involved should we proceed down this road, lol, I waved to them gallously in my RVM as I squatted that suspension like only a 3 series can squat rear suspension, coupled to the exteme visual camber change I was king that day, ohhhh yesss I woz;):cool:
 
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As a mere yoof I had a BMw 323 shark nose with an aftermarket back box( twas a black one, the zorst that is) and it sounded the dogs danglies with the straight six.
Plod stopped me (cos they were jealous, obviously, and had questions ready about stuff like Insurance/tax/affordability lol), they commented on exhaust note, I simply said to them how much paperwork is involved should we proceed down this road, lol, I waved to them gallously in my RVM as I squatted that suspension like only a 3 series can squat rear suspension, coupled to the exteme visual camber change I was king that day, ohhhh yesss I woz;):cool:
Sounds great mate lol.
Did you remove middle boxes? Cat etc? Or just change back boxes ? Thanks
 
No cats in the 80s, and no white dog sh*t on pavements either (never got to the bottom of that connundrum, pun intended:D)
no middle box removal either, just whipped off rear silencer and fitted (Janspeed?) rear. Regardless of the sweet and purposeful sound it made I more than likely made it slower, which ironically gave me more time to savour the 4 barrel fed six. lol
 
I've only heard a 4.4 V8 petrol with the rear box removed which is loud.
I'm not sure if you have cats on a Diesel or whether the exhausts boxes are required for back pressure on a Diesel but you could talk to one of the specialist exhaust manufacturers,there are a couple on eBay that advertise, and see what they say.
There are bypass valves that can be fitted but a straight pipe may sound nice briefly but would probably get annoying on a run.
Needing back pressure in the exhaust is a load of bollocks. What you need to do is maintain the velocity of the gasses on the way out. Go too big and the gasses will slow down, which will create back pressure, slowly down extraction of exhaust from the engine. Keep exhaust gas velocity high and you get a low pressure behind the gasses which aides extraction. The issue of removing restrictions willynilly is it can reduce the efficiency of the exhaust by removing the vacuum effect which leaves more exhaust gasses behind, impairing extraction from the next cylinder.
 
No cats in the 80s, and no white dog sh*t on pavements either (never got to the bottom of that connundrum, pun intended:D)
no middle box removal either, just whipped off rear silencer and fitted (Janspeed?) rear. Regardless of the sweet and purposeful sound it made I more than likely made it slower, which ironically gave me more time to savour the 4 barrel fed six. lol

Some cars were fitted with them in the 80s.
 
Needing back pressure in the exhaust is a load of bollocks. What you need to do is maintain the velocity of the gasses on the way out. Go too big and the gasses will slow down, which will create back pressure, slowly down extraction of exhaust from the engine. Keep exhaust gas velocity high and you get a low pressure behind the gasses which aides extraction. The issue of removing restrictions willynilly is it can reduce the efficiency of the exhaust by removing the vacuum effect which leaves more exhaust gasses behind, impairing extraction from the next cylinder.

As you can tell from answer I am no expert on exhaust systems, or anything else for that matter, but the point I was trying to make is the same as you in that if you remove components from the exhaust system it could be detrimental to the vehicle's performance.
 
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Some cars were fitted with them in the 80s.
Aye, pretty much everything that the world wanted to sell in the US.

As you can tell from answer I am no expert on exhaust systems, or anything else for that matter, but the point I was trying to make is the same as you in that if you remove components from the exhaust system it could be detrimental to the vehicle's performance.
Sorry, I wasn't meaning to sound like I was having a go at you, I just see "you need back pressure" a lot online and it is a daft statement. For some reason it is one of those daft "performance tips" that won't go away.
 
Sorry, I wasn't meaning to sound like I was having a go at you, I just see "you need back pressure" a lot online and it is a daft statement. For some reason it is one of those daft "performance tips" that won't go away.
It is a consideration if you have camshaft overlap
 
It is a consideration if you have camshaft overlap
By having vacuum extracting exhaust gasses, overlap means you can draw in fresh air and have a cleaner cylinder for the next burn. Back pressure with overlap would force exhaust gasses backwards through the valves and result in a dirty burn. Not to mention slow down the flow of clean air.
 
I think the back pressure theory goes back from before even i was a kid which was obviously somebodies misunderstanding of what was actually going on but knowing that if your remove your exhaust or the boxes attached to it can actually make it run worse not better and they assumed it was a lack of back pressure or restriction from the exhaust's silencers.
Everyday is a school day
 
By having vacuum extracting exhaust gasses, overlap means you can draw in fresh air and have a cleaner cylinder for the next burn. Back pressure with overlap would force exhaust gasses backwards through the valves and result in a dirty burn. Not to mention slow down the flow of clean air.
And when the opposite bank is next to fire on a V arrangement?
 
And when the opposite bank is next to fire on a V arrangement?
The plenum chamber is of similar capacity to the engine. So there should be sufficient clean air without having to scavenge from cylinder to cylinder. If that isn't what you were referring to then I have no idea why you think having exhaust gasses back up into the cylinder is a good thing. But I am genuinely interested to hear why.
 
The plenum chamber is of similar capacity to the engine. So there should be sufficient clean air without having to scavenge from cylinder to cylinder. If that isn't what you were referring to then I have no idea why you think having exhaust gasses back up into the cylinder is a good thing. But I am genuinely interested to hear why.
When the opposite bank is next to fire the low pressure behind the gas you theorised on is lost. The v6 (leaving aside the turbo) and v8 don't fire in a series of opposing banks.
Increase exhaust size / flow too much and valve overlap can result in some intake charge being lost out of the exhaust valve.
 
So you remove the centre box or rear silencers, make your rangie louder, more expensive to run, and anything over 60 on the motorway you have to provide your missus with ear muffs?? why not just buy a saxo off some youth for 400 quid who's just driven it through Halfords and be done with it!! :D:D
 

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