Dude, you also have to be looking at weight (especially when you compare newer cars with older ones) and probably other mechanical issues like gearbox ratios and whether there's an LSD etc.
Furthermore, its no use just having more power, its whether the chassis can make good use of them.
Take for instance BMW's mighty M6 with 500 bhp compared against a rather bland Porsche 911 which has about 350 bhp (there or thereabouts). On windy, narrow, challenging roads, the 911 will absolutely spank the M6, eventhough there is a huge difference of power in favour of the BMW. Why? Because the Porsche makes good use of the grunt it has while the BMW struggles to put it down. Its the same, I reckon, with the Integra type-R vs the Astra VXR and many other cars with more power, because the Integra is a wonderfully balanced package as a whole and everything works together well and there is no excess and nothing goes to waste.