Do E36 (M3) backboxes fit?

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suzie650
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Post Sun May 18, 2008 7:06 pm

As per title, do e36 m3 backboxes fit under an e30 without major modification and without dragging on the ground? Otherwise, what backbox do you know that will fit with inlet size approaching twin 2.5" or single 3"?

Cheers
Seb
jaistanley
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Post Sun May 18, 2008 10:55 pm

I think the STD M3 ones are too big to fit in the aperture. Aftermarket ones can fit.

I bought a blue flame back box with a mind to modifying it to use with my S50 conversion, but have decided to go a different route. You are more than welcome to make me an offer on it, it's un-used. It has what looks like twin 2.5" pipes.

I'm going to fit a Supersprint M3 backbox and have the centre section fabricated to meet my BTB manifold and Xpipe section. It will have twin 2" all the way through, and that's for the S50B32. Make of that what you will...
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Jhonno
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Post Sun May 18, 2008 11:10 pm

Jai.. You are just a great big copycat arent you?! :P
Got cable ties? Get diffin..

Arch roller for hire.

www.zeroexhausts.co.uk

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bodger
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Post Sun May 18, 2008 11:13 pm

e36 m3 bacboxes have one tailpipe longer than the other to follow the e36's rounded bumper where as the e30 bumper is straight so may look wrong
suzie650
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Post Sun May 18, 2008 11:33 pm

bodger wrote:e36 m3 bacboxes have one tailpipe longer than the other to follow the e36's rounded bumper where as the e30 bumper is straight so may look wrong
Thanks for pointing that out, I totally forgot about it...

jai, I might come back to you... depends what I find around first.
jmc330i
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Post Sun May 18, 2008 11:36 pm

The standard E36 M3 backbox is too big to fit in the space on an E30 - its much bigger than I realised. As Jai did, I got a Blueflame backbox (for the E36 M3) and modded it to fit the E30 - it does have 2x2.5" inlet pipes.

My Blueflame box would almost fit without mods (except hangers) but the pipes ran directly under the diff and cut the ground clearance I did have to an absolute minimum - they wouldnt have lasted very long.

In the end, I cut the tailpipes off (they were at the wrong angle for the E30) and cut the inlet pipes about half way down their length (from the box). I then got the box fitted into place and re-angled the inlet pipes to meet up with the middle section. Once that was done and I was happy with the placement of the rear box, the tailpipes were ready to be put back on - I still havent got round to doing that yet :o:
James
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Karan
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Post Mon May 19, 2008 8:38 am

try and go for twin 2.5 all the way thru,

sounds epic :cool:
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reggid
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Post Mon May 19, 2008 9:39 am

What lump are you running that might need a twin 2.5" :eek:
suzie650
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Post Mon May 19, 2008 9:42 am

doesn't need twin 2.5", 2.25" would almost certainly suffice
M60B40... quite a lot of air to get rid of...