172 cup exhaust woes

[scruffydubber]

Hi. I have some exhaust questions I could do with some advice on.
I have built my own 172 cup exhaust, I wanted it to be free flowing, low budget, and quiet. It's 2.5" and two boxes. The mid box is as long as the tunnel to try and keep the noise down. I tig welded it, made some mounts up and was pretty chuffed with the results.

That was until I drove it, it's loud, very loud and just drones and it's still currently got the cat on.

So I'm thinking of going to a stock exhaust. When does the stock exhaust become a power restriction? I'm planning breathing mods, 182 manifold and maybe cams in the future.
Or would I be better trying to reduce the noise on the 2.5" system. Maybe a noise killer baffle insert?

 

[Bluebeard]

A good quality second hand system is about £150-200.

Surely it's not worth the grief making your own??

 

[scruffydubber]

Show me some?
All the ones I have found have been very small bore longlife crap. Or single box systems. Neither meet my requirements.
I already had half the parts. So it cost considerable less then a 2nd hand one.
For me part of the fun is doing these things yourself.