Wastegate ported enough?

[awdtalon4451]

JunHey tuners, after a rain out at work I decided I was gonna piddle in the garage with my exhaust housing. I found some old grinding stones and 60grit flap wheels so I disassembled the WG arm/flapper and started porting (this is for an External WG off the o2 housing)
Ive put about an hour or so behind this and have opened it up to where the WG flappers edges used to be but im not sure if I should stop now or hog the entire outlet open. I want to go further but id rather be safe than sorry. Ive searched for threads showing a finished product but have had little luck. Ive read "Oldmans" porting thread but little light is shown on fully porting it out.
Also I wanted to know if I could port match the o2 housing gasket? Any help is appreciated. Heres a before and after pic. The before pic is off google and is just to give an idea how much ive removed. Thanks, Jared

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[Seamus]

Whoa, u went way too big. That housing is junk unless u wastebate from the o2 housing.

 

[awdtalon4451]

It is for a WG off the o2.

 

[RonRonTSI]

in that case ported more!!!

 

[JusMX141]

Looks perfect- stop there. Any more and you'll likely end up with a housing that cracked externally. You don't want to remove too much structure from that portion of the housing.

 

[007jimmy]

Dont forget to seal up the hole where the flapper arm goes through.

 

[Eclipse2630]

When porting the waste gate hole do the light test. Go in a completely dark room and take a flashlight and try to shine light through it while waste gate flapper is closed. If you see no light then your good.

 

[awdtalon4451]

When porting the waste gate hole do the light test. Go in a completely dark room and take a flashlight and try to shine light through it while waste gate flapper is closed. If you see no light then your good.

The WG arm and assembly have been completely removed for an external WG on the o2 housing. No need for a light test with it removed

 

[Bud92gsx]

That prett nice.Either thats a new housing or you sure do clean things up well..The smoothing looks wonderful.

And you have verified that the wg will open 90 degrees?

 

[awdtalon4451]

Looks perfect- stop there. Any more and you'll likely end up with a housing that cracked externally. You don't want to remove too much structure from that portion of the housing.

Ok cool, thanks guys. How does the bottom of inlet to the o2 look? Should I round the bottom of it more so it transitions smoothly?

 

[Bud92gsx]

I was discussing porting with Jusmx one day..He was telling me that porting tooo much can actually make you go backwards as far as performance goes..

So leave it like it is, and call it a day.

 

[TJCTalon]

Whats the point of having a 38 mm Wastegate off the o2 if the size of the port isnt much larger then 34-35mm?

I think the more you port the more boost control you have.

And justin is correct for the older mitsu housings, but the new evo 3 housing are so thin already and are made of better materials you dont need to worry about cracking with them.

Honestly Ive only seen bad cracking with the old 6cm housings, Id port more but thats just me

 

[Bud92gsx]

The ebay housings have a higher iron content than the mhi ones.And will rust.I know from experience.

So measure twice cut once kinda thing, just be careful.

 

[RipperXX]

Mine still creeps with my external setup, but I didn't port the passage NEAR as much as you did. I took maybe 2mm more out of the passage, looks like you went way beyond that. Please let us know how it works, if it didn't hurt your spool-up with such a large WG passage, then i'll get some new gaskets and bolts I guess and re-port mine some more.. cause creep is annoying.

 

[awdtalon4451]

That prett nice.Either thats a new housing or you sure do clean things up well..The smoothing looks wonderful.

And you have verified that the wg will open 90 degrees?

Thanks, its an older housing with about 30k in it. I did this with the cheap grinding stones from Lowes (it took all of them but it got the job done in a little under an hour) and the 60grit flap wheels I mentioned earier.
The area circled in the pic is what I was concerned with as it has a semi hard drop.

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[awdtalon4451]

Just bumping this to see if it needs to be addressed. Thanks

 

[RipperXX]

I went out and out a tungsten carbide, carbide burr to go back at it on mine. I want it to where it will sit at 1BAR @ WOT to near red line for daily driving and tuning, i'll go up from there. As of right now, it goes to 14-15psi (1BAR) stops...then starts climbing again after I think about 4500rpm up to nearly 20psi by 6,500rpm. This makes it a PITA to try to tune, plus I need a bigger fuel pump to support it as the un-rewired Walbro 190lph pump just isn't enough.

Did I mention I put the stock cat-back on mine to try to help stop this, it helped, but still creeps even with the stock catback and a 38mm Tial MVS external setup...seriously wtf Mitsu? Use bigger WG passages!

 

[Eclipse2630]

The WG arm and assembly have been completely removed for an external WG on the o2 housing. No need for a light test with it removed

so with this hotside housing with a EXT. WG off the o2 housing the flapper gets welded open correct?

 

[Bud92gsx]

Thanks, its an older housing with about 30k in it. I did this with the cheap grinding stones from Lowes (it took all of them but it got the job done in a little under an hour) and the 60grit flap wheels I mentioned earier.
The area circled in the pic is what I was concerned with as it has a semi hard drop.

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That left side for crepp is what to be concerened about.I think your fine