I have a GSL SE and I hear everyone speaking of 5-6 ports not opening. Can someone please explain why the ports actually do and how they work?
I'm also planning on adding a header for power gain, will this effect the ports?

Thank You,

 

adding a header will not effect the ports..think of the aux ports kinda like a v-tech system they are closed till you reach around 3000 - 4000 rpm then open for low range torque and mid range torque i personally have my completely removed so my low end is crap but i have a decent top end. Honestly youy want to keep them unless you plan on turboing your 6 port

 

If I can recall, the additional ports open when at a certain vacuum, as mentioned like V-Tech without the punch..lol.

I recall my old GTU and Convert S's, were excellent engines, but not enough power to satisfy my right side of my brain. Throwing upgraded parts at is is marginal and will net you some gains...but nothing like a turbo. You can supercharge it thou...hummm....

 

Actually ( I think ) the GSL open under exhaust pressure coming back from a pipe attached to the first CAT. area .. There are lots of good articles in the search area on this subject ..