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Couldnt u just drill holes in exis airbox,
So far i've decatted and just took the outer mesh screen off the maf .its got a bit more noise with no loss if power/fuel consuption.but seems a little more free reving..
Gonna look at taking some of the packing out of the muffler next .slowly slowly.want a bit more noise but not too much .
M

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Z4M-2006 wrote:How much do you think the exhaust hinders if you do all the intake mods..?

I quite like the exhaust sound as it is..

Modding the exhaust alone gave me no gains. It was only after doing my Eureka air-intake mod that I got any gains. But once I'd done the Eureka mod, doing further intake mods, coupled with my exhaust gutting mod, yielded further gains. Only from datalogging can you see what works and what doesn't, and the total gain is the aggregate sum of a collection of mods working in conjunction with each other.

AlienZed wrote:Couldnt u just drill holes in exis airbox,

NO! NO! and thrice No! The Z4M has a ram-air intake system!

interesting mods! need to get hold of a spare air box lid

pilchardthecat wrote:This is my cheapo induction noise mod.

You could've just cut away all the plastic beneath the CF skin and left a margin to bond the CF skin to the plastic lid. In essence you've used the sonorous properties of CF to get an induction noise in the same way that the front of a violin is made of quarter-sawn spruce for its sonorous quality, whilst the back is made from maple for its sound-reflective quality.

You should manufacture the part.

exdos wrote:

Z4M-2006 wrote:How much do you think the exhaust hinders if you do all the intake mods..?

I quite like the exhaust sound as it is..

Modding the exhaust alone gave me no gains. It was only after doing my Eureka air-intake mod that I got any gains. But once I'd done the Eureka mod, doing further intake mods, coupled with my exhaust gutting mod, yielded further gains. Only from datalogging can you see what works and what doesn't, and the total gain is the aggregate sum of a collection of mods working in conjunction with each other.

Thanks...

I have emailed you about the "eureka" mod btw...

exdos wrote:

pilchardthecat wrote:This is my cheapo induction noise mod.

You could've just cut away all the plastic beneath the CF skin and left a margin to bond the CF skin to the plastic lid. In essence you've used the sonorous properties of CF to get an induction noise in the same way that the front of a violin is made of quarter-sawn spruce for its sonorous quality, whilst the back is made from maple for its sound-reflective quality.

You should manufacture the part.

My intention was to cut the whole section away yes, but my saw gave out and so I resorted to drilling big holes. This one was only supposed to be a temporary experiment to see if making a complete cf airbox would be worthwhile so it was a bit of a hack job - I never expected it to stay on the car really, but it worked so well I left it

I used just a couple of layers of cf and 3 of resin so it is very very light and thin, lots of nice noises get out

I would love to get these mods before I get the remap done.

You fancy doing this pour moi...pretty please??

Tiko

pilchardthecat wrote:

exdos wrote:

pilchardthecat wrote:This is my cheapo induction noise mod.

You could've just cut away all the plastic beneath the CF skin and left a margin to bond the CF skin to the plastic lid. In essence you've used the sonorous properties of CF to get an induction noise in the same way that the front of a violin is made of quarter-sawn spruce for its sonorous quality, whilst the back is made from maple for its sound-reflective quality.

You should manufacture the part.

My intention was to cut the whole section away yes, but my saw gave out and so I resorted to drilling big holes. This one was only supposed to be a temporary experiment to see if making a complete cf airbox would be worthwhile so it was a bit of a hack job - I never expected it to stay on the car really, but it worked so well I left it

I used just a couple of layers of cf and 3 of resin so it is very very light and thin, lots of nice noises get out

Really interesting mod, does it still seal as per the original for the ram effect? More noise must mean less pressure?
Where did you get the cf sheets from?

daz05 wrote: Really interesting mod, does it still seal as per the original for the ram effect? More noise must mean less pressure?
Where did you get the cf sheets from?

If I've undrstood it correctly, any holes are covered back up. The extra noise comes from having thinner material (the carbon fibre) ather than the thicker plastic.

Yes, it's completely air tight and sealed - easy to check, just push it under a sink full of water and check for bubbles

AlienZed wrote:Couldnt u just drill holes in exis airbox,
So far i've decatted and just took the outer mesh screen off the maf .its got a bit more noise with no loss if power/fuel consuption.but seems a little more free reving..
Gonna look at taking some of the packing out of the muffler next .slowly slowly.want a bit more noise but not too much .
M

Sent from my GT-I9300 using Tapatalk 2

As exdos said, the airbox is pressurised by the ram air system, and overall it is very well designed - you do not want to leave holes as this will reduce the pressure. There are some things you can do to increase the pressure and/or retain more of it/reduce losses - this is what exdos and myself have been messing about with

Also, it's not a good idea to remove the mesh from the maf screen and just leave the plastic air straightener - the plastic alone does a poor job of inducing laminar flow (there is a reason they stuck the mesh on there). You need both, or something that fulfills both functions as per my mod. You might not have noticed it, but there will be points in the rev/speed range where you will have turbulence around the maf, and the mix will be off

pilchardthecat wrote:Yes, it's completely air tight and sealed - easy to check, just push it under a sink full of water and check for bubbles

True, nice idea, a tidier version would sell I'm sure. Applicable to all the M cars too.

Thanks for the info guys starting to understand wot your both aiming to achieve, your tech knowledge is great.
Well done.
Just off for a blast round the peak dist then put Zeddy to bed for 10 days.
Off to Salou on tues so i'll start again when we get back.
Cheers Moz

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AlienZed wrote:
Just off for a blast round the peak dist then put Zeddy to bed for 10 days.

I may spot you then