there seems to be quite a large lip on the turbo side of the up-pipe, although they are very nice this wouldnt seem to be condusive with good air flow.

is it worth having this lip ported out before fitting...?

 

Im not sure but email Andy F if he doesnt reply to this. Im sure he said he uses GT Spec Gen II headers

 

cheers Money, they are totally gorgeous to look at though, a real piece of work!

 

You can port the step out but then you would need to also port out the turbo to match and possibly find a bigger bore gasket ?
The step takes it from approx 58mm bore down to 52mm bore which matches the other aftermarket uppipes in circulation at the moment.

Andy