*Yes, exactly the risk with a too free flowing system on any vehicle.
Likely the muffler complimented the header, and moved the powerband higher.
This is why I personally feel that some intake flow must be added, this does help some with that.
One could advance the camshafts a couple of degrees, perhaps. The computer might not like that much, though.
It would be easier to put manifolds back on and keep the pipe and muffler setup.
Restricting in the pipe and muffler is the wrong place to create backpressure....It does have that effect, but it also affects mid and top end...Tricky stuff with modern engines....*EB
Since I don't use the powerband much above 3500, could I get away with running a more restrictive muffler than the hi-flow, without suffering adverse effects to the engine(longevity), in your opinion. I would rather not have to put back on the exhaust manifolds and x-over if I don't have too, it was PITA to take them off, and I already had the heads off at the time.
It would be easier to put manifolds back on and keep the pipe and muffler setup.
With the 3.0 I am not sure if this would be any better than what I have now. About a year and half ago I had the exhaust seperate prior to the cat while driving down the highway. I immediately noticed a loss in power, not a gain. I understand that the a free flowing cat/exhaust isn't the same thing as no exhaust at all, but it seems that some type of back pressure from the exhaust system is still needed.
