Side exit exhaust

[e21-Mark]

I would like to run a side exit exhaust on my track car and just wondered if anyone knew of a pattern I could copy? I'm only running a stock m20/2.5 but will a single silencer be below 105 decibels?

I would like the system to exit the offside just ahead of the rear wheel ideally. Any help and/or advice appreciated.

[drjim]

I had a single cherry bomb in the front pipe of the slug and straight pipe behind which hit 103-104dB. For last trackday I stuck a bodged up OEM rear silencer on to the back end, and I got 86dB but went as fast. Noise isn't worth it.

[e21-Mark]

Lukasz races a side exit with an m10 and it makes 97db so is definitely do'able.

[Duracel79]

Mark,

It may be possible, would be best with an M20 if you keep it a twin pipe system with a tailpipe out of each side.

Makes it harder for them to noise test then and should be quieter. To try and keep it quiet you would need a very good centre silencer and maybe a small silencer either side going from the middle to the outlets.

Ben

[Duracel79]

PS Power out of these BMW engines is all about the manifold, cross-pipe position and centre silencer. Downstream of these just needs to be non restrictive.

Ben

[e21-Mark]

It's a 316 shell though and not keen on going to trouble of converting again, after hassle & expense it's been with MIB. If it was a balls out, full race spec m20 (which I'd never waste my money on when an s50 or 54 is so much better) I might be more concerned about extracting every last bhp, but it's a stock 2.5 and I'm keen to save weight instead. I'm not gonna pretend that I don't also want to look of a side exit system.

[Jason_323i]

I toyed with the idea of running a side exit out where the fuel tank used to be and cutting a hole throw the sill.

Is this one LHD

[e21-Mark]

No, sadly not. The guys at Rally Prep are going to be doing it and were thinking of doing the same thing.

[pandemonium001]

Found this picture of an E30


I am interested in this one as well, purely for the look's TBH. I have thought about modifying one tank, picking up on the tank mounts and running a route similar to the vapour vent pipe but then out the rear qtr above the sill. lots of insulation and box in that area.

What fuel tank position are you using??

must admit i started to drool when i saw this!!


full car here.
http://www.velocidadmaxima.com/~wwwvelo ... 8&langid=1

[e21-Mark]

I would imagine it'll be centrally mounted just behind the new rear bulkhead, with the swirl pot next to it. It should be plenty far enough away from any exhaust pipe.

[TopCat]

While we are on the subject of exhausts - can anyone advise what are best rear boxes (I am after a 6 Cyl Rasp or a Hartge rumble) as well as being less restrictive and lighter than the enormous Swiss things we have at present?

[e21-Mark]

Give Mick a ring and he'll hook you up with Keith @ www.questmotorsport.co.uk who'll be able to help.

[pandemonium001]

Which side, should we be mounting it? kerb side or off side???
For me the kerb side is going to work best with the fuel tank delete, but there is a lot of conflicting info on the net.
and SVA or Traffic enforcers available for a sensible answer?