leecavturbo

worth porting a 10.5 housing? will be going on a ported mani and better O2
i've got a new 10.5 housing and before fitting thought i'd ask?
i saw some diy porting posts with pics any links to them?

sparky

iTrader: (1)

At least gasket match the turbine housing inlet flange ports and the exhaust manifold outlet flange ports to the stock Mitsu gasket.

Kracka

iTrader: (49)

Its definitely worth porting/coating the turbine housing, especially if you're doing everything around it. At the very least gasket-match the inlet to it matches the exhaust housing.

leecavturbo

ok thx
did i see someone completely removed the rib in the wastegate hole?
i'd like to fettle it a little but i'm sure its there for strengthing i've many other turbo's with cracks around the hole and maybe this brace is to prevent that?

still can't find thoses pics i have searched

racer135

iTrader: (2)

Porting the wastegate side will reduce boost. Dont port the wastegate side unless you have any kind of boost creep issue. Even with boost creep it is most likely caused by the O2 housing.

leecavturbo

surely if unwanted gas can escape easier creep will be reduced?
why would boost be reduced surely i'd just need less duty cycle on my ebc
if more gas can flow wastegate wise?

Aby@MIL.SPEC

iTrader: (161)

Definately.

I did a back to back, oem hotside/exh. mani & saw decent gains. i have a evo 8 & cams were cosi m2's @ -2in/-1ex.

it all works together.

i have a 3" dp/o2 housing combo....

i highly recomend a invidia o2 housing

these are the gains that i saw...I had to turn the boost down, via the ebc, but i ran out of range with my solenoid....I installed the hotside with the same preload!!

The boost response is amazing & you just feel the turbo spool up during city driving a lot better. Honestly, i noticed a difference just driving away going for the initial test spin



here is a 3rd gear spool up compare of my oem evo9 vs ported evo9 vs ported fp-grn. wot portion started @ 2500 rpm for ALL 3 pulls, same road, same fuel load, similar ambient conditions

racer135

iTrader: (2)

If the wastegate is shut boost is the same. Once it opens it will lower more boost with the same WGDC. I guess your boost curve will be more saggy also. You will have to play harder with your WGDC curves.

sparky

iTrader: (1)

What exactly do you mean by, "the wastegate side"? What exactly do you mean by, "reduce boost"? By the"wastegate side", did you actually mean to write, "hotside"? You've lost me!

apagan01

iTrader: (299)

ther are some very basic reasons why one would port the hot side, better top end is one of them, some will say to clip the blade tips on the hotside wheel, although not reccomended therfore porting the housing gets the job done

hope it helps, it helped me, i ported hot side on my 10.5 and my exhaust mani

sparky

iTrader: (1)

OP: I used to think that by boring out the turbine bypass port, that is eliminating the center wall in the bypass port passage, I could improve flow out through the bypass port.

However, I learned here on EvoM that this wouldn't be a very good idea at all. Since the 16G turbo is a twinscroll design which divorces exhaust gas pulsations. By eliminating the divisory wall in the turbine housing's wastegate bypass port you would be defeating the twinscroll design concept by creating exhaust gas reversion from one side across into the other.

The most you can do to improve exhaust gas flow out though the turbine bypass port is to open up the entrances to the bypass port by easing the tight radius into the bypass port in the turbine inlet area of the housing. You can't really increase the diameter of the port at the wastegate puck because it is already pretty much optimized as cast and you would risk leakage because the flapper valve has a bit of horizontal play across the seat.

racer135

iTrader: (2)

Wastegate side is where the flapper is located. Flapper side.
On this image the turbine side is ported and the "wastegate side" is not ported.



For more info go to COBB Tunning and read ther tech bulletins.

sparky

iTrader: (1)

So? I still don't think that your reduced boost assumption carries much weight.

edardnaekim

iTrader: (21)

I think what he is trying to say is that having a larger "flapper side" would allow more gases to be past through once the waste gate cracks open therefore reduces boost?

sparky

iTrader: (1)

Yeah, if the WG side as he calls it flows better, then it follows that turbine bypass flow should improve. Yes, the WG's sole job is to"reduce" turbine rotational velocity by bleeding off exhaust gases before they hit the turbine blades. The resultant reduction in shaft speed slows the compressor wheel thus reducing boost pressure.

So, he hasn't really reinvented the wheel. When the wastegate opens, it is supposed to "reduce boost", duh.