| Archive for The Motor Forum talking cars since 2006 |
| Racing |
Indulging my inner barry boy (now with pics)Yup, just picked up the 135i this morning from Munich Legends who had fitted it with a BMW Performance Exhaust for me.Sounded gorgeous on start-up - a lovely creamy burbling that is entirely new. It then did not greatly different to before for the majority of the drive back into London - seems to be lower down that it sounds noticeably throatier and richer (and louder). But, when I finally arrived at work having battled through South London traffic, it did sound absolutely terrific in the office underground carpark - every inch the burbling thoroughbred straight six with a psychotic edge! I gather it takes a few miles to bed in and for the proper exhaust note to develop - I shall look forward to seeing what happens! |
||
| Twelfth Monkey |
I get the impression that it's lower down the rev range that drive-by regs stifle exhausts. Even in sport mode, the exhaust baffles on my car close from 1700-2200 rpm (or so). | ||
| Dr. Hfuhruhurr |
There's an almost comically pronounced increase in noise in mine at around 4000 rpm | ||
| gonnabuildabuggy |
BMW's (well mine at least), have a vacuum operated valve that shuts down one outlet under 3,000 rpm - if that's gone then the car will instantly sound throatier.
The cheap solution is to remove the vacuum pipe and plug it with a golf tee - I did that for a while but then I thought the noise in the mornings might be annoying my neighbours. |
||
| simonp |
I'm toying with buying a new pipe for mine. Been looking on youtoob for vids, but the sound is usually too poor to tell if the zorst sounds good or not. | ||
| "him" |
How much of the system was replaced? | ||
| SpecB |
The Prodrive exhausts were the best extra I have put on my car. They too really come into their own at about 4k. | ||
| Blarno |
You can't beat a decent system. Mine is reasonably quiet at town speeds, but lets out a real throaty roar at full chat. | ||
| Racing |
The back box and certainly also much of the central pipe section too. This morning, I take it all back - it is much louder, especially if you have the windows open. Starting it up this morning from cold elicited a tremendous din. 
|
||
| "him" |
Superb, you must try and get a recording for this thread | ||
| Parm |
Cool. I'd consider getting a sports exhaust for the IS. Lexus do an offical one, but it's only available in the US. | ||
| "him" |
Does an after-market one affect the warranty? | ||
| Dr. Hfuhruhurr |
Not if it's a BMW Performance part, I wouldn't have thought. |
||
| "him" |
That was aimed at Parm really, I assumed that the BMW one would be OK from a warranty point of view... | ||
| Racing |
Well, I finally managed to take some pics of the 135i with its new 'zorst. Sounds more and more awesome too - a full throttle take-off in first produces a furious bark worthy of a much more exotic machine!
|
||
| TimR |
Nice.
I like exhaust tips that are a straightforward cut pipe rather than rolled. |
||
| Jasper |
Ooh, they are shiny. I expect you to keep them that way! | ||
| Matt |
Nice tips!
Shame the standard exhausts weren't as meaty. |
||
| "him" |
Looks good, I am amazed how similar to the standard system in design it is though, perhaps that shows how good the standard one is?
It would appear that the extra "naughtiness" is released by the deletion of the front silencer and a small increase in diameter. I guess the main collector could be a little more free flowing too? 
|
||
| Martin |
That does look great, different but still looks like it belongs on the car rather than an aftermarket job.
I prefer the finish of the standard pipes (rolled tips) though. They absolutely have to be kepy shiny! |
||
| Gurney |
Looks superb, not aftermarket at all. Think I prefer the straight cut as well. | ||
| PG |
The straight cut looks best. | ||
| Blarno |
Straight cut is the best. I remember my 405 having an outwardly rolled tip on it's original backbox, looked like the base of a condom....
Does anyone else find it weird that backboxes have taken on a strange, soapbar shape nowadays? They used to be cylindrical or oval ended cylinders. |
||
| "him" |
Indeed they did, I am amazed at the shape of the Focus ST backbox, surely having the gases turn through 2 90 degree angles can't be the most efficient way to get the gases out? Inwardly rolled looks better than outward IMO, but straight is good too... |
||
| simonp |
The 197 backbox is a huge heavy thing and by going aftermarket you save a fair few kilos, I believe.
When are we going to get a sound clip of this beasty then? |
||
| GonnaBreakABuggy |
Noise regulation and emissions control for you that, they're deliberately trying to slow the gas speed down so the pulses diffuse and cool off, which gives marginal emissions gains on the factory tests, the funny shapes are to create resonance chambers to damp specific frequencies of sound. | ||
| Mark |
The standard 135i tips aren't rolled. |
||
| Racing |
Um, they looked rolled to me? | ||
| "him" |
And how would you know?
|
||
| Twelfth Monkey |
I trust you'll be adding a 'zorst recording to the relevant thread, now under 'The Best of..'? | ||
| Parm |
That looks great Racing. Would love to hear it. | ||
| Mark |
Really? I thought they would have been the same as those on a 335i - they're finished, but I certainly wouldn't say they were rolled like this- 
|
||
| "him" |
|
||
| Mark |
Ah - so they are. Oops. Soz. |
||
| Rodge |
On the subject of zorsts, and I see some have been both mentioned and pictured above, Has anyone got any recommendations for somewhere to get a decat for my car, an E46 325i?
I've looked on Ebay but can only find them for diesels! I'm thinking of keeping the car for a bit longer, so am keen to improve the performance.. Back on topic, Racing, the new zorst looks great. |