[mattliston]

That intake cam looks to have gone one tooth off. On the pic, it looks one off, anyway. Does it look straight up? One tooth can make a large difference at high rpm, where the timing distance is more critical. Many cars can be slightly off timing, idle smoothm, pull fine in the low and mid ranges, but suck at top end. check to confirm this, again, as it looks off by the picture.

Post back and let us know. In the mean time, you could pull the spark plugs and check them, pull the cap off the distributor and check that and the rotor. make sure those things are somewhat clean, and no burn spots or anything on the rotor metal or cap metal contacts.

 

[mattliston]

Timing belt looks a little loose, but the cam does look closer to be lined up.

Your graph for the horsepower looks really good, just has less overall power then what should be there. have you tried any sort of additives or cleaners? I recently cleaned my enguine with seafoam run through a vacuum line, and it feeel a lot more alive, HIlls that it would struggle to go up in turned into hills that it only strained a little. iIm also getting better gasmileage, 280 per tanke turned into 350, same driving style and conditions.

As for the exhaust, the difference between 2 and 2.25 is barely noticable, so I wouldnt worry about it

 

[mattliston]

Agreed, long drives are the only way to really clean your engine internally. Gas gets in there from cold starts, detergents in the oil dont get a chance to work 100% if it doesnt flow through a warm system for a long time.