Exhausts - anyone built their own

[IainB]

Well, all being well the car should be back with me sometime in June (but didnt I say that last year....)
Anyway, one of the things that needs doing is a exhaust system, already have a set of manifolds (though they need a bit of work to fit) which leaves me with the main system to build.
Looking at a side exit - just in front of the main wheels (styled like most of the CCSE cars ) just wondered if anyone has attempted anything similar and has any hints tips, especially on tubing suppliers and silencers (looking for something 'cheap', not restrictive but sensibly quiet - the last 2 contradicting themselves!!)
Looks like from here on in its all going to be my own work
Cheers
Iain

p.s. needs to be capable of handling 550bhp N/A - 750bhp on gas - so therefore around 3.5" to 4" bore

[TomWilko]

I have a mate who's dad owns his own sport exhausts business. Not that i know the first thing about them

[CocoPops]

4" bore through out! nice

That's gonna have one hell of a sound exiting the "pipes".

[IainB]

4" bore through out! nice

That's gonna have one hell of a sound exiting the "pipes".

Thats what im worried about
Somehow I need to run a cam in - which is going to mean sitting at around 2500 / 3000 revs for approx 20 mins - for which I dont think my neighbours will be happy - it wont be " " im guessing - hence trying to find some 'quiet' silencers that arent power sapping, though saying that Steve Pateman (he of the quite mad Calibra) sounds lovely on tick over/low revs, but his silencers cost around £400 EACH
It also needs to get through an MOT somehow - and be 'useable' on the road without having to wear ear plugs.
Just found someone on another forum whos offered me his tube bender, but it can only do upto 3 inch pipe, which I think is going to be too restrictive..... need to get my calculator out again!

[Moby-Dick]

hehehe ask powerflow

Jiff says ask these chaps:

jpexhausts.co.uk - apparently they'll do anything you want.

[IainB]

Cheers Moby,
Unfortunatley money is a 'problem' at the mo - so im looking to do this job myself
Manifolds need a bit of tweaking as 2 of the runners sit where the steering column wants to go, but otherwise look OK.
Then it should be as 'simple' as running 2 tubes down both sides with a 45deg bend at the end into a slash cut - though I may have to bring the sills up so the pipe sits 'inside' the car - its low enough as it is at the moment without me having pipework hanging down underneath!
Unless.... I go for a crossover pipe just after the headers - which opens up a complete can of worms.....

[Jiff Lemon]

Is it going to have to be road legal? I'd be tempted to go for putting box section through the floor for the pipes to run through, as you want to be running as big a pipe as possible. Running a single 4 inch pipe is better than running 2 x 2inch pipes.

Give JP a call - they know they're stuff REALLY well. (take a look at the web site - go to manifolds, and look at the GT40 Replica.)

[IainB]

Jiff,
Had a look around the site - most impressive might even use them just for the pipe work..
Its not a single 4" - its a 4" on each bank of cylinders running 2" would create WAY too much back pressure!
The car has to be road legal for the series I want to enter - were looking at either cutting part of the floor and welding higher up the chassis or putting a 'kink' along where the pipes will run. Its an old car, so the strength is in the main chassis rails, the remaining is just 'floor' the rear has already been replaced with alloy panels