have new ptc 6262 air cooled bb 63 exhaust housing, using with thdp, hole in ex housing seems pretty small should i port it or leave it alone? and how much is ideal if yes? what are the pros and cons, of this,
You should need to port the wg hole to 1.0-1.1" Make sure you don't go outside the puck.. Just as important, or even more important is the radius going into the wastegate hole. Picture the air flowing up out of the header and having to make that turn through the hole. If you work on that radius turn you'll see most of the improvement in the boost control. The PTE exhaust housings have alot of material there. Make sure you blend in the top of the wg hole too. You can do this on the car. When you are done porting, you start the car and the material will blow out the wg hole.
Run it with the wastegate disconnected and see how much boost it makes. If you rev to 5600 and it makes 16psi this will be the least you will be able to make. Typically if you are running the turbo where it's making the power it should you shouldn't need to go more than 1.1" on the hole. If you are making less than 500hp you will need to go larger.