The folks at West Coast are great. Everyone I've spoken with there has been super knowledgeable and helpful. I have a couple of their Bark boxes and universal exhaust ports installed. If they offer an air filter upgrade kit for your saw that can help add some power and performance as well.
Several companies will port the cylinders on your 500i as well, which, at normal elevations, turns it into a fire breathing dragon. I would go with Ripsaw to get that done. Quite a bit more expensive than a ported muffler though.
CNC Performance Port Work for your chainsaw. Mail your saw to Ripsaw to reliably increase your saws performance. All Mail In Chainsaw Porting now receives a Ripsaw Signature Series Exhaust (when available for your model saw).
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