Quad Exhaust Issues

I'm really keen on the quad so yesterday I went to get some quotes. I went to the leading 3 shops in town and I got the same response from all... "we wont even quote it"

I showed them some pics of the eisenmann setup and the cool double back box setup as done by jonnymito, and after a bit of arm twisting I got 1 guy to consider it, if I get him some more info.

sooo....

The info I need is the dimensions of the standard back box - Height x length x width and if possible the dimensions of the eisenmann - L x H x W
He also wanted to know the distance between the inside of the left and right tips, so he can figure out how much pipe is needed and how to charge for it.

Does any body know any of these dimensions, including the distance between the quad tips and pipe lengths if possible?

I really really want this quad to happen TIA

Okay...

Standard back box... get under your car, you lazy git

I'll have a look at the Eisenmann dimensions when I get a chance - not sure why he wants that though?

Your man should be able to work out the distance between the centres as the setup is symmetrical. Just take the distance from the standard back box to the centre of the rear bumper - although that won't give you the exact pipe length though as it is kinked, how much he'll need will depend upon where he brings the pipe out of the back box.

On thing to note, the Eisenmann system has a flexi section in the pipe:


Full thread: Eisenmann Quad Sport Exhaust

If he can work in something like that it would help with the finer positioning of the RHS pipes.

Having built my own quad system set up I really can't see what knowing the back box dimensions of another system is going to do for your fitter?

Frankly he needs to pull the rear bumper cover off and look at the space and work out where he'll route the pipe. Having then picked whatever backbox he feels is suitable off the shelf he just mounts that on the LHS, T's into it and works a pipe run across, some sort of collector and pair of tips. The size tips and location is up to you controlled largely by the existing LHS outlet.

Couple of shots from my research inc the second using the existing back box (Femme T iirc)




how I started to plan my install - pretty simple

But Then I'll have to get off the couch 8) Nah ur right, just figured real oem or something may have the exact measurements, but I'll go dig out the tape measure and attempt it.

He wants measurements as he doesn't keep a suitable back box in stock so will need to order something in (which I would like to fit 1st time round) and the current box needs to be cut off, can't just unclip it and test fit.

Have read your thread a few times, it's the only reason I know this conversion is possible, and a big part of the reason I want to do this lol. Otherwise I would have been satisfied with a simple replacement box.

Tbh none of the exhaust shops were willing to cut the bumper i have to do it first, then take it back for fitting. He said he wanted more info basically so he didn't underquote me, as he says he's never even seen a z4 let alone attempted such a job and it could take him many hours in labour to make the cross pipe. So the more details I give him the less he has to guess, which equates to lower labour cost to build it.

Edit: this post was supposed to be above cj's - but I was too slow

CJ you make a lot of sense. No need to know the eisenman dimensions really. As long as the new setup is the same or smaller size then the oem box. So thanks for the offer PS but probably not worth your time and effort to check the size of your box.

My guy told me he wouldn't T into a box unless he had a diagram of the internals and even then he wasn't really keen. Which is why I'm favoring the double muffler option in the link in my first post.

And I don't really wanna mod the oem box as I want the system to sound a bit tougher/ exotic when I'm done.
I might have to twist his arm and ask him to pull of the bumper and have a look. I don't think he will until I cut the second hole in the bumper tho, but I don't wanna cut it till I have a solid quote.

How much would you image to build the pipe, collector and tips? As I know the cost of swapping out the back box already

Thanks for the help guys

hmm turns out measuring is harder then I imagined. I cant get far enough under as my chest/shoulders hits the bumper . dont suppose anyone has an old back box in their garage they wanna measure for me?

otherwise I have to wait till the weekend as my jack is at a mates place :roll:

PS - has anyone cut the rear bumper themselves? and if so did/ would you use a dremel to do the job, or will that chip the paint along the cut?

Had to cut my bumper myself after the guys that fitted the exhaust made a mess of it. I used a Dremel to do mine - just make sure you use a low speed or you'll melt the plastic. There is a section of "undertray" on the RHS that you will need to remove - something to practice your technique on! The tricky part is getting measurements right. I found I got slightly different placements for the cut out on the first few tries, so just kept doing it over until I was getting the same placing each time. Your other issue is that the plastic is rolled under from the cut out, this needs doing or it just doesn't look right. It's not that difficult, just requires patience and again lots of checking and double checking.

The cutting is easy so I didn't document any of that, this is the write up for creating the rolled under section...
Quad bumper conversion

I still need to get mine in and painted properly though

Youre all :gfight:

Just run straight pipes to the back!! The bloody thing already has 4 cats and 2 resonators to quieten it

EdButler said:

Just run straight pipes to the back!! The bloody thing already has 4 cats and 2 resonators to quieten it

Click to expand...

I take it this is what you're doing now with your neverending exhaust mod, Ed? Look forward to seeing / hearing it

EdButler wrote:
Just run straight pipes to the back!! The bloody thing already has 4 cats and 2 resonators to quieten it

Click to expand...

lol my last car was a turbo skyline with a 4" exhaust, resonator delete and a canon muffler I could fit my foot in. and people could hear me 2 streets away!!
add to that it had over 300rwhp, no traction control, LSD or ABS - it was an animal

I feel like the BMW should be a little bit more refined...

btw I managed to get under the car for a rough back box estimate (using tape measure) and the dimensions i got are 57cm x 36cm x20cm (W x L x H) in case anyone else wants to know.

seems like everyone wants quads atm 8)