Merge collectors

[Exhausted]

A friend told me that this thread was getting some attention so I thought I might put in my 2 cents.

IMO, I have never seen a exhaust port that was smaller than it needed to be.
If you can change say header tube size or step length, or no-step to two step, or collector diameter or length or 421 to 4into1, and not see any difference your motor is not sensitive to what kind of a header it has on it. Another way of saying that is your header is not working to add anything to the way the engine runs, is it?

It is certainly possible that whether you buy headers that come in a box or made for you custom, if the above is the case, it is not simply the fault of the header, ok?

If you do not want to change things in the motor so you can gain the extra power available from the exhaust system, then keep bracket racing and praying you don't have to run heads up with someone who does.