I ordered an hmf and a dyno jet kit, Im at sea level (0) and need to rejet with stock airfilter. What else should I do while I have the carb off? Can anyone explain how to port the Y going into the head in detail. Its the piece that narrows up at the carb.

 

You should find a way of getting more air through the airbox cause your engine is gonna suffacate

 

Im not real woried about that, I get a plenty of air.

 

Porting isn't for beginners,asking how to do it is a good indication that you don't have the experience you should have before taking on this task. Making a mistake could be very costly.

And why would you get into porting when you still have the stock air filter? Porting alone doesn't do much, you have to open up the rest of the engine to get a worthwhile benefit from it.

 

Porting would do a lot if you had the modifications for it like a cam. Porting allows better air flow by have your intake or exhaust ports reamed out by a professional it make a larger and a larger surface for air to travel smoother through the engine, it can be a bit pricey around 400 too 600 dollars. Porting increases low to mid range perfomance, and sometimes sacrifices top end, but its normally worth it.

 

i will do it for 375 with the intake match and exhaust over size valve are a little more and not that much of a gain . the porting it self is the best mod cause it is usually what people do last and it should be first.