fg xr6 turbo, my tuner did a tune on standard intercooler but with after market steel pipe and air intake, it made 320 rkw , lot more than I expected, is it safe run on this kind of power level with stock cooler/ my tuner said it's perfect fine, but I still but worried might blow up something, also can the factory zf cope with this kind of power level?

Can't see why not unless your going to track it with continuous wide open throttle. Squirts here and there shouldnt be a problem. I've got 315rwkw with my standard BF F6 intercooler and havent had a problem and it still ran 11.7 on the strip. Factory ZF will handle it easy.

As long as AFR,s are fine then there is no real issue. It will suffer heatsoak quicker thou.

In the day I ran 300rwkw on a Stock BA XR6 turbo intercooler many times over. It also ran consistant 12.1 sec passes @ 116mph at willowbank with it to. When I did change to a bigger cooler it made 315rwkw on lower 1psi boost and ET a 11.8 sec pass @ 119mph

Intercooler isn't a power mod

More for safety and consistency

intercooler gives power gains and AFR is not the concern with IAT's

I would have thought any decent cooler has power gains due to spark advance with lower charge temps.

spot on

what mods?

My experience at 285rwkw with stock cooler was ok on the street, but at the track I got bad heatsoke.

It's not the intercooler that is the concern, it's the way the tuner tunes the car to react to higher Inlet Air Temps to keep the timing at a safe point.