[Insoc]

I have had two Alfa GTVs with the first resonator removed. In both cases the engines had Polished and Ported heads, larger valves etc...

With my lastest GTJr it had a new exhaust system installed when I purcahsed it. the car suffered from breathing problems, and I took it to the muffler shop to have the front resonator removed. When we put it up in the air, we saw that the front resonator was already rusting from a hot spot caused by too much back pressure. Off it came, and the engine liked that much better... When we removed it we checked it for blockage, but there was none.

So I assume that a stock engine does like the stock exhaust layout, but a modified one, for me two engines have been like this, enjoy not having the front resonator.

I am in no way proving anything with my statements, and have done no testing. I am simply sharing my experiences...