DIY Exhaust Mod – Gain of 10+ HP!!!

[Benjamin]

I'm a little confused as to why the holes need to be at such a steep angle where lots of people are having trouble getting the hole started. Isn't any place you can reach on that pipe still in the same chamber and would produce essentially the same results? Why not shoot for deeper in the pipe where the angle is much shallower and easier for the drill to start?

[chipmunk]

I see no reason why you can't drill anywhere along the pipe, as long as you are still within the middle compartment and your drill bit is long enough. I drilled roughly in the middle of the bend. I first created a notch with a screwdriver and then used a 6mm drill and worked up.

For info, I have just ordered 20mm and 25mm drill bits and will be amending my video so you can compare the difference in sound between the smaller (10mm, 13mm, 15mm) and the bigger holes.

[EssexPorsche]

Guys,
I'm sure it sounds different, possibly better than stock. But i don't see that you are bypassing any chambers at all.
I think the flow of the arrows is wrong on that picture.
Starting on the left (red arrow) the gasses enter here. They collect and equalize in the second chamber (when counting from left to right). When the pressure is sufficient, they progress - still from left to right - to the fifth chamber on the far right.
The final journey is from the collection chamber on the far right round the curved pipe and out.
Yes, there is some over-spill equalization in the center chamber but its not the primary route as gases in there eventually get pushed back to the left or right.
So why would you want to drill a hole in the pipe which is actually helping the exhaust gasses out (i.e.) the curved pipe. Surely doing this hinders the flow of the gas by allowing it to escape into the center chamber and hence hinder the expulsion.
Well.....that's how i see it anyway. ha ha. But if you like the sound....fair enough.

[particlewave]

Originally Posted by EssexPorsche

Guys,
I'm sure it sounds different, possibly better than stock. But i don't see that you are bypassing any chambers at all.

That's essentially correct. However, you are allowing some of the exhaust gas to bypass all but chamber 3 and go directly out the exit. This is similar to the Porsche sport exhaust, except that the amount of flow through the drilled holes is restricted by the flow through the baffle in chamber 3.