leecavturbo

good quality part tho ? i won't behaving any trouble with it?

racer135

iTrader: (2)

Mine is working great so far. Same thing as the original but with bigger inlet ports.

sparky

iTrader: (1)

Do you have a couple of more angles of the volutes pictured in the image in post #45? Same image different lines of sight?

EDIT: Or at least, clock it 180* for me, please.

sparky

iTrader: (1)

Yeah, don't mess with that area highlighted in Red. In fact, I'd just scribe the entrance to each volute using the stock gasket as a template, but I wouldn't grind those edges until the end. Or, if you do grind them then protect them with masking tape.

EDIT: Actually this is a very useful image. If you look at the volute on the right hand side, you'll clearly see the turbine bypass port's exit opening. A lot of people just call it the wastegate "hole". There are two bypass ports(one for each scroll). We'll name the bypass opening pictured as the short-side bypass port.

Why, short-side? Because the wastgate opening pictured is closest to the flapper valve. It is a direct dump from the turbine inlet area, without the need for an actual internal, crossover passageway. The other scroll's bypass port is necessarily longer and follows a more tortuous path, as the bypassed exhaust gases are routed behind the other inlet area before reaching the flapper valve.

I've found that with the stock engine and the stock turbo, you can get away with just porting the short-side bypass port pictured in the image above. Do you have your coloured markers available, lee?

leecavturbo

yeah
yeah i've pretty much had a good look at the "formings" of the turbo and dam if we had the time/money to cast a better more flowing casting it would be massively improved.
as you say the passage way for gas exiting the wastegate from the volute on the left (my pic) is horrendous.
the gases hit a wall at 90° to the direction the gas enters the inlets before exiting the dump!
we all know smooth turning radius is the way to flow air not to mention the turbulence this must cause for gases entering the scroll!

sparky

iTrader: (1)

So, working with just the inlet area on the right now, if you were to superimpose a vertical and a horizontal axis, a crosshairs, which will have its center point almost in the middle of the wastegate hole. Then we should be able to degree the areas which need to be ported.

sparky

iTrader: (1)

I'll be back in five mins. as my battery power is low.

leecavturbo

grid you say ?
.

sparky

iTrader: (1)

O.K., I am going to focus in on the edge of the wastegate hole itself, forgetting for a moment the rest of the turbine inlet area, until we can agree on the exact location of the critical area.

sparky

iTrader: (1)

What you need to grind is only the initial radius to the wastegate hole. The only area that really concerns us is located to the right of the vertical purple line. Next I'l give you the horizotal coordinates.

leecavturbo

this thread should be named the most detailed turbo porting guide with pics ever lol.

sparky

iTrader: (1)

Actually, you'll be restricting most of your grinding to the crescent-shaped area of radiused edge between the vertical purple line and the vertical white line. Of course, you'll want to blend, or feather, the sector that you radius into the adjacent edge segments. Are we in agreement on the location, lee?

leecavturbo

here in white?
.

sparky

iTrader: (1)

As cast, that edge has about a 90* radius. When you're done grinding, you should, approximately, end up with a more open 120* included angle radius.

sparky

iTrader: (1)

Yeah, you could extend the white marker on the bottom of the area in question to the left just one more vertical line. So, that it starts at the nearest(furthest right) red vertical line and not the purple. Otherwise that's about perfect.