Exhaust - "NAM - Need Another Muffler"
I can't begin to think how many mufflers/exhausts this car has been through since we picked it up.Manifolds
The stock manifolds on a quad-cam are pretty restrictive. Unfortunately, due to the quad-cam being a 90° vee, there was absolutely no room to run anything else. The exception to this was the RHS manifold, that also had to somehow manoeuvre around the pesky steering linkage and rack. This resulted in the rather nasty, but necessary, manifold seen below. The 4th cylinder outlet had almost no clearance between it and the power steering linkage (5mm at most). The welds look fairly rough, but had been cleaned up quite nicely internally.
Pipes
Nothing surprising here. Just a bit of pipe (or is it tube?) connecting everything together.
Mufflers
The car generally ran a hotdog on each bank of cylinders, plus a SuperTrapp. The hotdogs, being in a relatively protected region under the car, seemed to survive quite well. On the other hand, the SuperTrapps required replacing almost every race. If it wasn't the entire exhaust system being ripped off, it was the SuperTrapp being taken out by a nasty big boulder or tree-stump. Aside from their obvious physical limitations, the SuperTrapps worked quite well. They certainly dropped the dB level of the car significantly, which was quite obvious when one got ripped off.
Wrapping
Yep; we wrap the exhaust manifolds on all our cars. Simple fact is that the things get really hot and start melting stuff that's nearby. It's commonly know that wrapping reduces the life of the metal used in the exhaust, and it's particularly bad for the welds, however this is not a road car and I can't remember an exhaust that was taken off because of old age... Another option would have been an expensive ceramic inner coating, but that'll get reserved for the I'm-going-to-be-buried-with-this car.
Spark Arrestors
Getting the muffler torn off is a big problem when you are required to run spark arrestors (generally long-course events where there has been little/no rain for lengthy periods of time). Note that this is not the case if you're running a reverse-flow muffler or a SuperTrapp. Spark arrestors are generally hand-made out of stainless wire mesh (see the CAMS regs for the largest hole dimensions), and it is a relatively tedious task to make them (what with bending pointy wires for a couple of hours and all). Try not to wipe out too many, as it will become annoying having to make more.
Note To Self
Don't locate the mufflers/pipes under the car where they can get torn off. This pretty much goes without saying, but the only reason we still ran them there was because we hadn't moved them somewhere else. The plan was to bring them inside the cabin (suitably boxed and cladded of course) and run them out the rear doors.
