the main issues with the other custom pleniums is the cars idle very badly. there is no inlet for the breather pipes from the rockers ( which doesn't conform to the epa. and they are alot of money for little gain. most people I have heard who fitted a custom plenium have had to go to custom ecu which in it self is not always legal. I have seen plenty of skylines make 250+ rwkw with the stock plenium. so why change unless as I said you want an all out race car.
btw if you can show me skyline with a custom plenium running the stock ecu and running well with cold start etc. I would be interested.
btw mat lowth on these forums is making 270 rwkw + with the standard plenium and probably more .
you car is fairly new and must drive beautifuly why ruin that if the are no major gains to be had.
meggala