3.2 or SC don't need no headers!
 

Many find a cat bypass adds about 4hp or a sport muffler adds about 4hp.

It has been verified many times that on a 3.2 that going to a 1 5/8 or larger full header system can add and addational 10hp such mods.

Many have also found that putting un equal length 993 style heat exchangers on a 3.2 or a C2 3.6 results in a solid addational 10hp bump on a 3.2 and more so on a C2.

However, SC's, Carrera's and 3.6's have non overlaping cams so there is little opertunity for any signifficant scavaging to occure anyway.

I suspect the main gain is from mostly divorcing each side of the motor. It seems thjis will alow for better evacuation of each cylinder and less contamination of the incoming air fuel charge.

Here is my thinking.

All motors must turn over twice or 720 deg to run through all cycles on each cylinder.

On a SC or Carrera, the duration the exhaust valve is open is 220 deg. Times 6 cylinders that is 1320 degrees exhaust valves are open over the 720 deg of rotation.

That is, every time and exhaust valve is closing, there is another pressureizing the joint header system and interferaring with its evacuation of exhaust at the closing exhaust valve.

Thus, the increased pressure means less exhaust will be expelled and less charge will be able to fill the cylinder.

Now, if we in effect split the motor into two equal fire three cylinders we will have exhaust open 220 deg time 3 or 660 deg of the 720 deg of motor turn.

Now we will have no other cylinders adding pressure just out side closing exhaust valves when the close and we will get better cylinder filling.

Cool stuff.

All we have to do is at the conection of where the HE's conect to the cat, euro muffler, or bypass, keep the exhaust seperate.

One way to to this might be to conect the right bank to a muffler inplace of where the cat was and exit straight out the drivers side. (Won;t work on a C2).

Then connect the left bank of cylinders HE to a straigh pipe around the first muffler, and make a turn to put a second muffler in place of the stock muffler and then exit the passangers side.

I bet because this would come very close to matching a B&B header or 993HE style conversion.

Just a thought. ;)