Originally Posted by mrphotoman
of course it is not going to make a major drop in power but it will affect your power. I would guess you lose about 3whp with that restriction.
an exhaust is only as efficient as its smallest point.
take a 6" coffee can and open both ends then breathe through it.
it is very easy isn't it.
now take a 6" coffee can and only open one end then poke a small hole in the other end and stick a straw in it.
breathe through the straw, big restriction.
now flip it over and breathe through the big end of the can, same exact restriction, lol. it does not matter if it is at one end or the middle or the other end. it will be the same restriction.
I think your example is extreme. Maybe you should take a piece of 2 1/4" PVC and reduce it to 2" and blow thru it and see if you can tell the difference. I would think Gary has increased hp rather than decrease it. He went from the restrictive OEM muffler which has baffles, 90 degree bends etc. to a free-flow straight thru design.