So, initially I thought my clutch was slipping. Under heavy loads the car was often studdering. Then today I was reading on this site that the studdering could be caused by spark plug blow out or a boost leak.

I think that I have eliminated the clutch slipping idea. I got out on the highway for my 20 minute drive home and did a series of pulls from 40 mph in 6th gear at WOT to 70 mph. Not once did it studder, it acceled smoothly the entire time. Then when I pulled from 3rd and 4th it did studder but when it was studdering I didn't notice an increase in rpms at all. I am mostly stock with AEM tru boost, borla exhaust, tien s, and k&n FIPK. The car does have 144k on the clock and did have its 120k maintenance.

What do you guys think it might be?

Thanks in advance, John