New Group Buy - BB ByPass System 3.2M 3.0Etc - NEW VIDS PG 8

M@r said:
{"]Well I'm going to collect my back box in a bit. So as long as everything has gone to plan I'll have some feedback to give. Only thing I'm concerned about is its going to seem very quite compared to the straight through on one side I've been dealing with since Saturday!! :)

Keep us posted looking forward t the feedback :thumbsup: ...... I had the same thing once when I owned a 350z had a hole in the BB for a month or two ... so decided to replaced the standard BB with an uprated SS BB anyone it seemed!!! so quite than before felt well disapppointed .... well at least there was no more drone!! :D
 
Guys, just got back from getting mine done - two words - DO IT!!!!! I'm so pleased with it, the noise is perfect. :trampoline: Its hard to describe, you get this increase in the 'rasp' when you put your foot down, not a chav like rasp, sort of like you hear on the old Ferraris. Absolutely no drone. Had a couple of miles on the A1 at 70, nothing :thumbsup: The beauty of it is when cruising I think the difference is hardly noticeable, it just rewards you when you put your foot down, so when you want it to. I think it must be because of the angle the pipes join in. I'm no expert but I think when the air is going through calmly, not under pressure its natural course is forwards through the back box, but when you put your foot down and the air is rushing through, its looking for any escape possible and therefore more is pushed vertically through the bypass pipe, hence the noise.

Here are a couple of before and after videos. I've measured it with a DB tester so you can see the increase in noise. You'll notice at tickover there is little difference, but when you put your foot down.... :yeah:

BEFORE:


AFTER:
 
Would be interested in this, do we just need a garage to drill 2 wholes one before silencer on after and then weld the pipe across. Is it 2 pipes per BB. Any one got a spare BB for a 2 litre lol save drilling current one
 
:o thats sounds amazing! cannot wait till friday!!!! :evil: :evil:

Great Vids thanks for doing that .... I take it the camera falling over was not part of the process :P
 
Paza3 said:
Great Vids thanks for doing that .... I take it the camera falling over was not part of the process :P

No it wasn't! That was the video of my very well (read bordering on OCD) looked after Galaxy SII falling face first onto my gravel drive :( So called Gorilla Glass now has a couple of scratches on it :headbang:
 
This is a great idea. But I have a few concerns.

How many of you have lowering spring? Especialy with the M, I have an Mc and it has H&R lowering springs. Recently with the incredible weather I have been hooning much more than regular and have managed to bottom the car twice... one with a good scraping noise that came from the back boxes of my exhaust. The clearence is less than 4 inches as it is, surely with the depth of the back boxes and obviously the cars that have been lowered it is much more likely to rip these small additions off and make quite a mess if the car did bottom. I was doing about 80mph hit a rather big hidden dip and that was enough for the loud bang and bottoming making the car jump around quite substantially... :?
 
This pipes go above the boxes - there is a lot of clearance above where they are mounted so no worries at all with that.
 
Oh rite, I see. I interpreted the images wrong. Sounds good!! So is the fitting basically available at any reputable exhaust fitter once the pipes have been purchased?
 
oli445 said:
Someone measure their 3.0i back box, I don't trust myself! Sounds awesome! :thumbsup:

Second that, I just haven't got the space to get under. Would be very interested in this though

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I would be interested in this if someone measured up a 3.0 SE! Don't think I will have time to measure mine for a while.
 
tomscott said:
Oh rite, I see. I interpreted the images wrong. Sounds good!! So is the fitting basically available at any reputable exhaust fitter once the pipes have been purchased?

Pretty much :thumbsup:
chessmaster said:
oli445 said:
Someone measure their 3.0i back box, I don't trust myself! Sounds awesome! :thumbsup:

Second that, I just haven't got the space to get under. Would be very interested in this though

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All I did was nick the jack out of the mini , jacked her up , measured it took less than 5 mins. Follow the original post/ my rubbish diagram.

I measured the underside for the lenght as the height is easy as he sends you additional lenght so a rought guess is fine/measure for the height.
 
tomscott said:
Oh rite, I see. I interpreted the images wrong. Sounds good!! So is the fitting basically available at any reputable exhaust fitter once the pipes have been purchased?

Yeah pretty much. What I did was take the boxes off myself and take them to an engineering place who are good at welding. As long as they can drill a 3/4 inch hole the rest is just welding.

Driving without back boxes on is fun too :o
 
This does sound very interesting. I'm in Australia so obviously this deal doesn't apply to me, but if someone puts up the measurements for the 3.0i I think I might try and get this done locally

Ps. Does anyone have a few pics of the pipes installed?

Cheers
 
Mark - the 3.0i boxes are welded on so we can't just unbolt them, might be a bit more difficult for us :roll:
 
One thing morries me : sound seems to peak at above 100 dBA.
Most tracks here in france enforce the 95 dBA limit.
Is it possible for you to try this : put the sound meter behind the car, approx 1.5 meter away, aimed at the exhaust from your standing height, and then revving the engine at 2/3 max RPMs for say 3 seconds ?
Thanks a lot.

Otherwise, it just sounds perfect. :wub:
 
Sure, I did mean to do that. I very much doubt it will be above 100db though, when you blip the throttle like I was you get the over run, which is louder than a constant throttle. I think it will be about 95db.
 
Shooter said:
One thing morries me : sound seems to peak at above 100 dBA.
Most tracks here in france enforce the 95 dBA limit.
Is it possible for you to try this : put the sound meter behind the car, approx 1.5 meter away, aimed at the exhaust from your standing height, and then revving the engine at 2/3 max RPMs for say 3 seconds ?
Thanks a lot.
I believe M@r]{ also has sport cats, so the sound levels/personality in the 2nd video won't be what anyone else necessarily hears.

Tracks in the UK measure at 3/4 revs (or just under 6000rpm for Z4Ms) - and mine standard system only measures 86dBA at those revs.
 
No didn't get the sports cats fitted in the end, turns out the problem wasn't with my Cats it was with my manifold. so all standard M exhaust except these bypass pipes
 
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