DIY Back Boxes.

[GeezerGarage]

I'd am at the point on my beetle (2.1 Stroker) where it needs an exhaust, I have raised the engine and it has a merged header so the exhaust would theoretically go straight through the rear valance in the middle. This is getting modified so it will curl around before the valance, sweep around the inside of the wing and exit just in behind the rear wheel.

Now here lies my dilemma, It's curse word loud. My MOT guys are sound (pardon the pun) but I just cant ask them to ignore noise that loud and possible fire.

A little bit of a pop is nice when dropping gears but I'd like to limit the noise a bit whilst not restricting flow too much. Has anybody got any experience with making baffled exhaust?

I have thought that maybe making a muffler with a deflector plate in the middle of it would be good and also some wadding. Or would a S bend inside any good?

Thanks in advance.

[ChasR]

Just to check, no 'stock' Beetle silencer will fit? I was about to suggest that you give the Turbo Trip silencer a go .

Jetex may be your people to talk to though; They make off the shelf silencers in addition to as far as I can tell, making a quiet Pug 306 GTi-6 exhaust system short of going for a genuine (but expensive) Pug system or a competent exhaust builder).

[DirtyBit]

are you looking for something like this, from a porker boxer,
986forum.com/forums/attachments/general-discussions/13872d1299200646-possible-make-986s-sound-like-996-c4s-muffler_cutaway2.jpg [/IMG]
lots a baffles, lots a pipes and two 90 degree bends should quieten it a bit.

[GeezerGarage]

Standard turbo tips won't work as it's going to be hidden.

the exhaust would be nice exiting out the middle but it's a bit too tight. And I'd like it to come out one side for the look I want and ground clearance.


I may be fussy and over complicating things but I'd like to make the thing myself as a learning exercise.

Here is what I have.

[phillipm]

How much room do you have to work with? Doesn't look like a lot!

[MrSpeedy]

I had a similar looking set up years ago fitted with a single side exit exhaust.
I believe it was made by/sold as a Kadron system
Dunno if they're still about tho

[GeezerGarage]

Kadron are still about, I've had one and they are not great, this is a bit different from how they normally sit.

phillipm, Not allot, I will cut all that and re-work it a bit.

[phillipm]

Simplest way to do a cheap box that's effective is to leave a chamber empty at the start and the end of the box, to allow the gases to expand, then have the centre packed with dividers in.

[GeezerGarage]

Great, that's the answer I wanted. It's good to get some simple info some times. Thanks, If I get this done I'll post my results.

[phillipm]

I'm just making one this weekend so I shall stick some quick pics up then for you anyway, but it's easy enough to imagine!

[Coo]

You can still get tuckaway boxes that hide under the wing I believe:
(although you may be cheaper making your own)

[Coo]

Linky:

www.justaircooled.co.uk/BEETLE-PARTS/BEETLE-PARTS-SPORTS-EXHAUST/TURBO-TRIP-TUCKAWAY-EXHAUST.html

[GeezerGarage]

Yeah I think for 100 quid I'll whip my pipe bender out and have a go myself.