hey thinkin of gettin this grow box 60x60x140tall will it be big enough for a 250w hps? what fan size an extraction should i get?

I run a 250 in a room 60 x 75 x 200 with a 4" extractor (with carbon filter) with a few PC fans for intake, temps get a little high during the summer but fine the rest of year. I would recommend you go with 5" extraction and 4" intake with a fan controller that way you can cover the summer temps and turn them down during the winter.

are you in england? summer temps ? ok what i had in mind is a four inch extraction w carbon filter to match(need to buy tent, filter an fan). i have a six inch clip on fan which is will use inside an also a 14cm pc fan for intake... sound ok? will also be buying 11litre pots an wondered what you would all recomend for first grow strain wise? was thinkin northern lights seedsman.?

Get a proper intake fan, you'll only have probs further down the line if you don't.............

You might be able to get away with the PC fan, maybe have a second to add should one not be enough, if the PC fans don't cut it you should be able to add a proper fan easily enough in a tent. PC fans make a stupid amount of noise for what they are, and mine are easily louder than the boxed 4" ruck fan.

To be fair the room I grow in is also my bedroom (living at parents) I have a PC, PS3, HDTV and stereo all pumping out heat and I was averaging 30C in the room during the summer (dread to think what the temps would be like if we actually had a proper summer) My grow cupboard hit a peak of 34C after lights on for a few hours but would be about 26C by morning (I run lights on during the night).

As for strain, I went for Nirvana, nice and cheap so you're not loosing a lot of money should things go tits up.