It's well worth it with a stock head Alex. I've just fitted a T25 on an Emtec equal length manifold to mine and it's a lot quicker than my G, 166bhp and stripped out, ever was. This is in a car with back seats spare wheel and sub box in the boot. I'm running pretty much the same setup James made 191bhp at Aldon with a few years back.No idea what boost I'm running though.