need help

[vk88ix]

like the title says need help idk what to do next
i changed
fuel filter
spark plugs
and its the same thing so heres the problem the rpms are haveing problems going passed 5 1/2 k it still redline at 6 1/2 but with alot of tweaking its the 2.5l engine

[camip]

I'm gonna guess vaccum leak.

[mikes325ix]

i think spark plug wires are old whos with me?