External Gate on 16g question

[ferruchnuts44]

Ok I'm going to be doing a tial 38mm external manifold mount wastegate and I'm wondering if it would be ok cutoff and weld shut the o2 dumptube I have now and be ok without welding the flapper closed? I'm wondering this in case I go bigger in the future and want to revert the turbo back to stock internal gate.

 

[dsm-onster]

Ok I'm going to be doing a tial 38mm external manifold mount wastegate and I'm wondering if it would be ok cutoff and weld shut the o2 dumptube I have now and be ok without welding the flapper closed? I'm wondering this in case I go bigger in the future and want to revert the turbo back to stock internal gate.

Have you thougth about us rigging a jig that won't allow the wastegate to open? Like metal strapping from the flapper arm to the actuator mounting holes. Why botch up your SS 02 housing?

 

[ferruchnuts44]

I figured the o2 dump would get in the way since I'll have a dumptube off the wastegate and it wasn't needed anymore, if it was recirced back in my downpipe I would just leave it alone. The strapping idea isn't a bad idea but I was going to remove the whole wastegate arm off the turbo to clear up some room around my coolant lines.

 

[90laserRSfwd]

you could just sell your exhaust side and get one set up for an external gate off the manifold

 

[DSMunknown]

When modifying an internally WG'ed turbo to an external, people have either

• TIG/spot welded the flapper shut
• left the flapper door completely alone
• completely uninstalled the flapper

Personally, I would recommend welding the door completely shut. Regardless, I completely support you in using an external 'gate on a 16G.

 

[90laserRSfwd]

just reread your post and what I have should have said was just to buy an exhaust side set up for an external gate

 

[ferruchnuts44]

When modifying an internally WG'ed turbo to an external, people have either

• TIG/spot welded the flapper shut
• left the flapper door completely alone
• completely uninstalled the flapper

Personally, I would recommend welding the door completely shut. Regardless, I completely support you in using an external 'gate on a 16G.

I'm sorta leaning towards welding it shut but is there any problems with leaving the flapper door alone with the wastegate actuator and arm taken off so it just flaps open? I was worried about it cracking/melting the welds or leaking at the o2 housing once the wastegate tube is taken off and welded closed. Thanks for help guys!

 

[T9S1i]

if you leave it loose and run a wastegate off of the manifold then the exhaust will go by the flapper and not spool the turbo. If you run the WG off of the manifold you MUST block the stock WG passage.

 

[97gstjosh]

Just weld it completely shut
Im running an EvoIII 16g w/ a Tial 38mm wastegate off my manifold on 20 pounds
right now and I love it. It wont fail you

 

[JusMX141]

Two tackwelds on either side of the actuator lever has done it for me in the past. I normally tack it while the actuator is still attached so there is plenty of preload holding the flapper door shut inside the housing.

A good DSM buddy of mine ran his 20G this way for two seasons at 25psi and had no problems with leaking or the welds breaking loose.

The tack welds can be easily removed and the actuator reinstalled. This way if you ever choose to resell the turbo you will be able to sell it to anyone instead of those who only run manifold-mounted external gates (less than 1% of the total DSM population.)

 

[ferruchnuts44]

Where exactly on the arm should I have it tacked? Where I have the arrows in the picture? I have no clue haha.
This is probably going to be the route I'm going to go being I'm more than likely going to upgrade sometime in the future and if I want to sell it I can go back to internal gate.

 

[JusMX141]

Weld the flat part of the actuator lever to the exhaust housing- not the actuator itself. I tack mine in two places on the top, just to the left of the white arrow in your photo.

 

[ferruchnuts44]

Weld the flat part of the actuator lever to the exhaust housing- not the actuator itself. I tack mine in two places on the top, just to the left of the white arrow in your photo.

Ok I gotcha, I was actually thinking that after I posted the picture haha. I'll see how it all works out this week once my tial 38mm comes in. Again thanks for the help

 

[RipperXX]

O2 mounted is easier IMO, thats what I did anyway.

 

[kmoore]

I'm sorta leaning towards welding it shut but is there any problems with leaving the flapper door alone with the wastegate actuator and arm taken off so it just flaps open? I was worried about it cracking/melting the welds or leaking at the o2 housing once the wastegate tube is taken off and welded closed. Thanks for help guys!

Like everybody else is saying, just weld it shut.

And no it won't melt the welds.

 

[JusMX141]

I was worried about it cracking/melting the welds...

Being that mig welding requires temperatures ranging from 6,000 to 10,000°F to fuse the metals, I don't forsee that being an issue.....unless, of course, your EGT's are somewhere in the 6,000-10,000 range!

 

[kmoore]

.....unless, of course, your EGT's are somewhere in the 6,000-10,000 range!

And if that's the case, you got bigger fish to fry.

 

[ferruchnuts44]

my bad

 

[turboglenn]

Use safetly wire to wire your internal gate shut then use the external. A word of wisdom, on that 16g, you'd be better off with a 44mm wastegate, teh samller turbos require more exhuast to be routed around them because they spool so easily, other wise you get boost spike and boost creep. Most likely you would get spike with the smaller gate

 

[kmoore]

my bad

We're just given ya shit. No biggie.

 

[ferruchnuts44]

Use safetly wire to wire your internal gate shut then use the external. A word of wisdom, on that 16g, you'd be better off with a 44mm wastegate, teh samller turbos require more exhuast to be routed around them because they spool so easily, other wise you get boost spike and boost creep. Most likely you would get spike with the smaller gate

Really? I hope its not too bad because I can't stand not being able to get on my car with it creeping how it is without one.

We're just given ya shit. No biggie.

haha, its cool. I would've done the same thing.

 

[97gstjosh]

You will have no problems with a Tial 38.
Im running an EvoIII 16g with a Tial 38 on 20 pounds and I
dont get boost creep or boost spike. Thats the whole reason for going External is to have better boost control not run in to more problems. I bigger gate like the Tial 44 is for running larger turbos with lower boost than whats normal.

 

[T9S1i]

yup my 38mm wastegate works great on my 16g

 

[absolute_DSM]

You will have no problems with a Tial 38.
Im running an EvoIII 16g with a Tial 38 on 20 pounds and I
dont get boost creep or boost spike. Thats the whole reason for going External is to have better boost control not run in to more problems. I bigger gate like the Tial 44 is for running larger turbos with lower boost than whats normal.

Not quite the whole truth.

Think about trying to run bigger boost. You want most of the exhaust flow to flow through the turbine = in relationship to the turbo size you would want a "smaller" wastegate size.

With a smaller turbo, there is plenty exhaust gas to go through that turbine to make 20psi at 3500 with a 38mm wastegate but at 7500 RPM with that 38mm at 20psi you may have a problem with the exhaust gas not being able to get out fast enough = boost creep. With a bigger wastegate you would be better off at higher RPM.

 

[97gstjosh]

Not quite the whole truth.

Think about trying to run bigger boost. You want most of the exhaust flow to flow through the turbine = in relationship to the turbo size you would want a "smaller" wastegate size.

With a smaller turbo, there is plenty exhaust gas to go through that turbine to make 20psi at 3500 with a 38mm wastegate but at 7500 RPM with that 38mm at 20psi you may have a problem with the exhaust gas not being able to get out fast enough = boost creep. With a bigger wastegate you would be better off at higher RPM.

I never thought of that part of the equation thanks for the info