What's wrong with my saw?

[Dvick1987]

My 455 rancher I pulled out of the metal dumpster at work had a blown up piston. It starts and idles well but I can't get it to rev up. Stuff I've tried after replacing the piston.
New fuel lines
New spark plug
New carb
New seals.
Cleaned muffler screen
Included is a link to a YouTube video I made looking for help and I demonstrate the problem. 
455 rancher woes (plz help) - YouTube
Thanks for your time boys. 

[Gary Davis]

its a husvarna pull the name plate off and put a different manufactures name on it and it will run just like its supposed to 8)   I would check the  the fuel line and filter then the carburetor 

[ladylake]

 Also check the impulse line and metering valve height.  Some have a hose for the impulse, some have a hole in the carb mount. Make sure they aren't clogged.  Steve  

[Mapleman]

It might be sucking air at higher revs, could be why the piston got fried in the first place...

[DHansen]

When you try to rev it up, say half throttle, will it die or stay running poorly?  What does it do at WOT, die? Or run poorly?  If it dies, pull out the spark plugs, is it wet or dry?  Does spraying carb spray around the intake boot affect it's running?

[Big_eddy]

Fail to rev can be spark or fuel. You have a new carb and new plug. Have the carb screws been adjusted? What is the high set at?
Have you tested compression? Although low compression is worse at idle. 
Have you tried a pressure test?
You might want to check the flywheel to coil gap. Than can affect spark.

[ladylake]

 If it has a hole in the carb for the impulse, check that real good, gasket on the right way, no silicone or junk blocking the hole.  Steve

[Dvick1987]

Thanks so much for the feedback! Update.
Replaced impulse line. All I had laying around was fuel line but I think it's doing the job? I have messed with the carb mixing screws extensively, starting with them both turned a half turn out. I did not test the seals yet. I will procure a vacuum pump next weekend and pressure test her. I will also try spraying the intake "boot" to see if it leaks when running. I'm in the national guard so I'm wrapped up all weekend but when I get back I'm going to try everything suggested. I watched a video from "tinman's saws" channel on how to vac test the saw but I am unsure on how i'd go about setting the metering lever height. Again. Thanks so much for everyone's time and feed back.