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Discussion Starter · #1 ·
here's a couple of pics of my porting on my spare head. yeah yeah, i know, the guides are pretty messed up, but I'm replacing them anyway, so i wasn't particularly careful around them. i just did my best to make sure that stuff was done evenly and uniformly though :)
 

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Nice work Derek, looks good. You wanna expand on the "techniques", what you're using, etc?
 

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Discussion Starter · #3 ·
well, nothing special. i used a carbide ball end bit to reach down around the guides to make nice even shaped contours that match on both sides of the guide. i did the same to intake and exhaust.

and i used the tapered rolls to work the leading ramps up to the guides and used a flat roll to smooth out the factory casting flaws that you can see running down the port walls and around (just below...er, above) the the seat area. i haven't gotten my new guides installed but, when i do, then I'll finish matching that area up. trying to get that all nice and flat is a complete pain and would be much easier if i had another one of those flapper wheels. I also smoothed a little out of the floor of the port. not much, but just made it a bit of a smoother transaction to go through it instead of over it.

i made my own long bit with a slot in it to reach way in. i took an old belt from a industrial belt sander and made my own strips( i think like 120 grit) to put in the end of it. works good. also, i finished the ports out with making strips to go in my long bit, made out of like 180 and 320 grit sand paper. gives it a nice smooth finish.

hey javad, do you think it is possible to safely bore the intake seat out
1-2mm on the turbo application. i heard that trick some where's else and was thinking about doing it. i wouldn't do it to the exhaust though.
 

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I would only remove the portion of the seat that doesn't seat the valve face, remember you need as much contact area there for head purposes. On NA motors I'll usually pull 1.5mm out of the ID, but never on a turbo motor, just go to a bigger valve and a bigger seat, and back cutting the valve is safer.
 

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Discussion Starter · #5 ·
if i backcut the valve, can i do it with a stock valve? i know there are two types of valves,one and two piece. could a two piece be cut back, or would i need a single piece stainless valve?
 

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I've backcut the stock valves with good results, you don't need to go too high up the valve, just on top to increase the airflow at low lifts, but again, be careful on the exh. as its not really worth weakening them for a little flow.
 

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Discussion Starter · #7 ·
hey javad or anyone else who might know...On my KH intake there is a spot cast into the manifold about the TB, but nothing goes there. can i grind the casting inside for were the bolts would usually go? whe I open the TB and look in, those little boogers take a lot of flow up.

also, can that tapered thing on the butterfly be removed? or does it change something in flow over the butterfly itself? it also lines up with the cast in things above it when it's fully open. so,hmmm....any thoughts?
 

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derracuda said:
hey javad or anyone else who might know...On my KH intake there is a spot cast into the manifold about the TB, but nothing goes there. can i grind the casting inside for were the bolts would usually go?
Probably.

That's where audi usually puts the intake temp sensor. On the KH it is mounted on the side.

when I open the TB and look in, those little boogers take a lot of flow up.

also, can that tapered thing on the butterfly be removed? or does it change something in flow over the butterfly itself? it also lines up with the cast in things above it when it's fully open. so,hmmm....any thoughts?
I remember a q-list post from Javad a few years back regarding that little butterfly piece. As I recall, no real gains from removing it, and light throttle transitions became more abrubt than usual.

Javad will of course provide more details on this :)
 

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Ya Derek, you can port the opening there and flow it if you want, but be careful about screwing with it too much, I like to leave the wedge in there, the throttle gets real jerky in street driving, "smoothness" is gone, as soon as you touch the throttle pedal the engine jerks under the abrupt entry of air, I'd leave the wedge and most of the features of the intake there as is, maybe smooth them out a little, but there isn't a lot of gains by messing with this area.

The dual port TB is very smooth becuase of the dual staging, adn the wedge and other features are put there to keep the progressive nature of the throttle opening intack, makes sense I'm sure.
 
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