Exhaust systems...

Mid America Motorworks? Or get some new heater boxes and bring the Brad over to the local muffler shop. I am sure they could bend you up something nice.

Brian, thats a good Idea, i might just do that if I can't find what I want and doesn't cost too much.

Jspbtown, I was thinking more along the lines of "zoomies" to work with heaterboxes, on the otherhand these do look like the height / profile I'm looking for. Thank you!

I use a Gene Berg Dual Quiet Pack, pretty much as Dave (above) spelled out. It's been coated with the real Jet-Hot Metallic Ceramic, and still looks reasonably good after 18 years and almost 400,000 miles since the coating. Similar exhaust systems have been in most VW catalog houses. Berg's was made in Mexico, so I doubt that the mufflers are proprietary, although his company may have done the collector.

Warmest...

4 into 1 is best due to the way the firing order is laid out. If you use "buggy duals", cyl 1 fires into the right exhaust then cyl 4 into the left followed by 3 into the left. 3 helps scavenge 4 out. then cyl 2 on the right which is followed by 1 on the right. 1 helps scav 2 but there is nothing scavenging the exhaust from cyl 1 or 3.

Tuned 4 into 1 is best as all pipes are equal length with equal bends thus back pressure is the same for all cylinders. with all 4 cylinders feeding into a common collector, each cyl benefits equally from the scavenging of the next cyl in the firing sequence.

A well designed header will lower back pressure. backpressure should be close to 0 psi at idle and rise to 1 psi at 2000 rpm.

It has nothing to do with heat. Oil in the covers will not burn no matter what setup you use.
They still get just as hot. Look at a set of headers at night, they will glow.

Here is somehelpful reading from www.thumpertalk.com/topic/571594-exhaust-backpressure-the-myth/

Backpressure: The myth and why it's wrong.

I. Introduction
One of the most misunderstood concepts in exhaust theory is backpressure. People love to talk about backpressure on message boards with no real understanding of what it is and what it's consequences are. I'm sure many of you have heard or read the phrase "Engines need backpressure" when discussing exhaust upgrades. That phrase is in fact completely inaccurate and a wholly misguided notion.

II. Some basic exhaust theory
Your exhaust system is designed to evacuate gases from the combustion chamber quickly and efficently. Exhaust gases are not produced in a smooth stream; exhaust gases originate in pulses. A 4 cylinder motor will have 4 distinct pulses per complete engine cycle, a 6 cylinder has 6 pules and so on. The more pulses that are produced, the more continuous the exhaust flow. Backpressure can be loosely defined as the resistance to positive flow - in this case, the resistance to positive flow of the exhaust stream.

III. Backpressure and velocity
Some people operate under the misguided notion that wider pipes are more effective at clearing the combustion chamber than narrower pipes. It's not hard to see how this misconception is appealing - wider pipes have the capability to flow more than narrower pipes. So if they have the ability to flow more, why isn't "wider is better" a good rule of thumb for exhaust upgrading? In a word - VELOCITY. I'm sure that all of you have at one time used a garden hose w/o a spray nozzle on it. If you let the water just run unrestricted out of the house it flows at a rather slow rate. However, if you take your finger and cover part of the opening, the water will flow out at a much much faster rate.

The astute exhaust designer knows that you must balance flow capacity with velocity. You want the exhaust gases to exit the chamber and speed along at the highest velocity possible - you want a FAST exhaust stream. If you have two exhaust pulses of equal volume, one in a 2" pipe and one in a 3" pipe, the pulse in the 2" pipe will be traveling considerably FASTER than the pulse in the 3" pipe. While it is true that the narrower the pipe, the higher the velocity of the exiting gases, you want make sure the pipe is wide enough so that there is as little backpressure as possible while maintaining suitable exhaust gas velocity. Backpressure in it's most extreme form can lead to reversion of the exhaust stream - that is to say the exhaust flows backwards, which is not good. The trick is to have a pipe that that is as narrow as possible while having as close to zero backpressure as possible at the RPM range you want your power band to be located at. Exhaust pipe diameters are best suited to a particular RPM range. A smaller pipe diameter will produce higher exhaust velocities at a lower RPM but create unacceptably high amounts of backpressure at high rpm. Thus if your powerband is located 2-3000 RPM you'd want a narrower pipe than if your powerband is located at 8-9000RPM.

Many engineers try to work around the RPM specific nature of pipe diameters by using setups that are capable of creating a similar effect as a change in pipe diameter on the fly. The most advanced is Ferrari's which consists of two exhaust paths after the header - at low RPM only one path is open to maintain exhaust velocity, but as RPM climbs and exhaust volume increases, the second path is opened to curb backpressure - since there is greater exhaust volume there is no loss in flow velocity. BMW and Nissan use a simpler and less effective method - there is a single exhaust path to the muffler; the muffler has two paths; one path is closed at low RPM but both are open at high RPM.

IV. So how did this myth come to be?
I often wonder how the myth "Engines need backpressure" came to be. Mostly I believe it is a misunderstanding of what is going on with the exhaust stream as pipe diameters change. For instance, someone with a civic decides he's going to uprade his exhaust with a 3" diameter piping. Once it's installed the owner notices that he seems to have lost a good bit of power throughout the powerband. He makes the connections in the following manner: "My wider exhaust eliminated all backpressure but I lost power, therefore the motor must need some backpressure in order to make power." What he did not realize is that he killed off all his flow velocity by using such a ridiculously wide pipe. It would have been possible for him to achieve close to zero backpressure with a much narrower pipe - in that way he would not have lost all his flow velocity.

V. So why is exhaust velocity so important?
The faster an exhaust pulse moves, the better it can scavenge out all of the spent gasses during valve overlap. The guiding principles of exhaust pulse scavenging are a bit beyond the scope of this doc but the general idea is a fast moving pulse creates a low pressure area behind it. This low pressure area acts as a vacuum and draws along the air behind it. A similar example would be a vehicle traveling at a high rate of speed on a dusty road. There is a low pressure area immediately behind the moving vehicle - dust particles get sucked into this low pressure area causing it to collect on the back of the vehicle. This effect is most noticeable on vans and hatchbacks which tend to create large trailing low pressure areas - giving rise to the numerous "wash me please" messages written in the thickly collected dust on the rear door(s).

This has been educational, it has helped me understand how the exaust works, its affects on the engine, overall performance, and why it is important to consider why the "stock" system is the way it is. Cool looks and sound don't sound so good and cool after all. Thats not to say that a good thing can't look good too, it just has to be in reasonable moderation.

Yes you can follow the KISS principal as many have, myself included. but it is always better if you have the resources to make an informed decision.