Yes it is better to a point, but if bigger was better shouldn't we just be skipping the 3" and going with 4"?

3" is only going to be better if 2.5"-2.75" is a restriction by causing too much back pressure, but just because you go 3" doesn't mean more exhaust is getting out or the system has better flow seeing that exhaust expands, when it expands it gets cooler and slows down. So the key is finding the right size exhaust to keep velocity up without causing too much back pressure.

 

i have a 2 3/4 labree high flo cat and miltek down pipe...then i have the 3 inch pipe still think i shud try to go smaller??? cause with the 2.5 i think there was to much back pressure and i was getting TERRIBLE gas mileage with the inch theres a nice garggle and such haha

 

you should be fine by that, the 2.5" cat should create enough back-pressure to work well

 

what exactly makes the garggle sound though??

 

Does it happen when youlet off the throttle?

 

Not having enough to absorb it like an extra resonator.

 

Sounds like when I disconnected my exhaust so there was no resonator or muffler, it hurt my ears doing 35 and keeping the rpms at 2000.

 

no dont go smaller. y would you want more back pressure?

 

if you are over exausted, you will actually lose power, there is a size that works best for every engine/setup.

 

Exactly. Just like you match the correct size IC pipes and FMIC to the size turbo and air flow it is moving.