Ported Head HP increase

[Jerith]

Over the weekend my timing belt broke, subsequently bending all 8 exhaust valves and 3 intake valves. Since my head is off, I'm getting it ported; how much of a projected HP increase can I expect? Just out of curiosity.
Thanks,
Jerith

 

[L2RTSiAWD]

Depends on how much you get ported and whether you add any other upgrades to the head.

 

[NosLaser]

On a 2G, it's usually worth more than on a 1G because the 2G's ports are smaller from the get go. If you are going to get it ported, I suggest doing it right from the get go. Have the combustion chambers polished (remove all hot spots, and unshroud the valves a bit) have the bowls ported (most of your power is found right there) and have a D port performed on the exhaust side, and just remove a little beyond the casting material on the intake side so you don't lose velocity, and merely gain volume. Also, have a 3 angle valve job performed as that will be worth power as well, and get the valves seals replaced. Also, make sure the guides are true. A head port job with the above mods can make a VERY big difference, but it's exponential. On the T25 you prolly won't see much of a gain, but when the turbo gets bigger, the gains will get bigger too.

Regards,

 

[lambertvr4]

If you're running a smaller turbo and plan to for some time, then I'd suggest the same thing as "NosLaser." No need to spend an a$$ load of money. You can expect noticeable gains even w/ a small turbo from the port job. And when/if you step up you'll get more bang from the bigger turbo. Check out Polk's post about the flow numbers. That can give you a guesstimate on the power increase to expect. 10% wouldn't be unthinkable.

 

[CBgst]

Originally posted by NosLaser
On a 2G, it's usually worth more than on a 1G because the 2G's ports are smaller from the get go. If you are going to get it ported, I suggest doing it right from the get go. Have the combustion chambers polished (remove all hot spots, and unshroud the valves a bit) have the bowls ported (most of your power is found right there) and have a D port performed on the exhaust side, and just remove a little beyond the casting material on the intake side so you don't lose velocity, and merely gain volume. Also, have a 3 angle valve job performed as that will be worth power as well, and get the valves seals replaced. Also, make sure the guides are true. A head port job with the above mods can make a VERY big difference, but it's exponential. On the T25 you prolly won't see much of a gain, but when the turbo gets bigger, the gains will get bigger too.

Regards,

So who could do a port job like this I was considering porting but I don't want to mess up my head.