So, about 3-4 weeks ago I posted a thread asking for help with my Silvia regarding temperature... recently I decided to make a ghetto bottomless portafilter by knocking off the spouts of the PF, while it isn't a birds-eye view of the extraction it's enough to know that something is REALLY not right, the shot started out beautiful but then started sputtering with very eccentric spurts of espresso. I immediately narrowed it down to a few things.
+ Tamper (I'm using a ghetto tamper much like the one they give you as freebies but better fit to the basket and aluminum) - Maybe not letting me get that extra umph?
+ Burrs are Worn - maybe the grind is not consistent enough, I really doubt it, but it might be possible.
+ The dose - I currently dose just to the rim of the portafilter, I do not overdose considering that huge screw up in the brew head makes it pretty difficult.
When I prepare the shot I do the following:
1.) Grind.
2.) Dose into the portafilter.
3.) Tamp
4.) Pull.
At first I thought the bitterness I was getting was my shot temp, but after seeing that gush of espresso I pretty much knew it was most likely related to that. My shots are tasting pretty much terrible on their own, I might be able to make a decent latte with them but straight.. Ewwww, They tend to pull around 24-27 seconds. Any tips? Maybe I need a new Tamper?

Sounds like poor distribution. Have you tried WDT?

I'll go try this now. Thanks for the suggestion.
Edit: Tried it, no difference.. I did the exact same process that was on the tutorial. Could it be tamp pressure?

You should make a real bottomless portafilter. Unscrewing the spouts will result in a flow that jumps around even if it was even.

I'll be sure to eventually I do not have time to at the moment though I have looked at tutorials to do so.