mate i got genie tri y to 2 1/2 to x pipe then 2 1/2 dumped behind both wheels

got a pic of that?

2.5" is droney on a 302. 2.25" is much better but a tiny bit droney. How much power are you making? A twin 2.25" is good for around 210-220ish rwkw.

The reason it's droney with the 302 is there isn't enough cubes to fill the exhaust properly. Believe it or not a 351 with the same system will be quieter.