| I can only imagine that the 45mm you have at the moment must be restricting it, particularly after the work your going to have.
When you think that a 45mm system is standard on a stock 748BP, then surely your 998 with higher comp/cams etc must be struggling to breath properly.
I see no reason why a 50mm full system shouldn't be used, and would think that you may be better off with something as big as 54mm. Especially as you are getting the other bits done, you could get the ECU etc set up to run sweet as a nut at the same time.
Its been said before that its not all about the overall size of the pipe, but if you are having engine work done, then it is definately benificial.
[Edited on 14-12-2005 by Harv748] | 
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