What exactly does it mean to split the exhaust at the manifold? Is this what is sometimes refered to as a "split six"? How is this done, and what would be the advantage in it?

http://www.pugspares.co.uk/Images/Pug205Mi16_ManifoldSplit.jpg

it's this, where you have a whole manifold on one flange, but the four ports feed into two pipes, before going into a collector.

the layout would be something like 4-2-1 (4 pipes at the ports, then into 2 pipes, and finally one)

a split six would probably be where 6 ports feed into six pipes, which then run into 2 collectors (each with 3 pipes going in) before the single (or possibly double) pipes heading to the rest of the exhaust.

so the split six layout would be 6-3-1 (or possible 6-3-2-1)

the advantage of it is flow capacity, as there's less flow restriction.

hope that helps.

So, it's basically headers? I have an '84 F-150 4x4 with a 300 inline six cylinder. (my project vehicle) The engine and drivetrain is good and strong. There are other issues that need attention first, but I'd like to learn more about this type of exhaust system.... difficulty, cost involved and availability of parts needed. - Thanx for the time and patience :)