Wastegate Flapper Disintegrated
 

Well I used to have a nice shiny wastegate flapper, but it decided to completely disappear. I have been troubleshooting boost problems for a while and this is what happened. Here is a before and after shot of my WG and a pic of the WG now after about 8 months.

But the sweet part is that I have had an S5 turbo & manifold sitting around waiting for money to send to BNR, so I swapped it on and it's awesome. Boost comes on much faster than my S4 even when it was working perfectly. Boost is great.

Wow talk about no boost. The machining on that hotsides looks really good. You about doubled the size of the wastegate. No boost creep for you.

looks like your welds didnt hold very well.

questions about s5 turbo?
is it bolt on straight replacement?

Do i have to remove the twinscroll seloniod and thats all?

thanks

Actually you can still see the welds, they stayed. The black steel washer I used is no more though. Yes the S5 is a bolt on replacement. You need a couple of the S4 lines and you need to cap off the Twinscroll vac line.

already been over this, you have to use hardened steel like an exhaust valve for a flapper. if you use a high iron content steel then it will get eaten away by the torch through the port.

if your porting skills are decent you can also get away by retaining the stock flapper as well, if you know how the air is going to move the most through the port.

Well I researched a bunch on here before I had the port done and I found that people were using a black steel washer so that was what I thought was sufficient. Maybe this thread can show people that BLACK STEEL WASHERS DON"T WORK!

im gona have to do do the same with mine. Ive tried porting it 2x ( still using original flapper door) and still boost creep. So i guess ill have to weld a piece to mine and port it more :(

best bet is find a machine shop that has some crap old exhaust valves for a few bucks.

What about cutting up an old brake rotor from the center? It's off of my '7. I pulled my turbo off today and sure enough the old washer is completely missing. I must not have noticed since the old existing flapper still closed 90% of the opening.

I just looked up the melting point of 304 Stainless steel and it say 1500 degrees celsius, which is 2742 degrees fahrenheit. I think that should work too. I don't know about the brake rotor though.

How would you weld stainless to a hardened steel? I think it can be done, but for this application? I'm going to look around tomorrow for a few exhaust valves, I have to go out to get some hardened bolts anyway.

What about the cast iron from a bench grinder shield? I have some that's about a 1/4" thick. Wikipedia says cast iron has a melting point from about 2100-2200*F.

use ss welding rods or wire.

stainless steel will both warp and crack and eventually break off due to varying expansion rates vs the base metals. i still believe an exhaust valve is the cheapest and easiest alternative to trying your own R+D to figure out what works. pulling the turbo and messing with the flapper can easily be an all day job each time you have to do it.

I'm painfully aware of this, and I avoid it if possible. My God, blowing turbo-mani gaskets one after the other SUCKS! I did pull my turbo this weekend and worked on this. I got a used exhaust valve from Arnold Motor Supply for less than $5! Kick ass! I hope the welds hold up, I used 6011 rod at 60Amps on a basic Lincoln arc welder. Any comments on that? If I have to pull the fucking turbo again I might just send it to BNR to have everything done professionally.

poor quality pics:
http://img63.imageshack.us/gal.php?g=0212102113.jpg

What's the T with a bolt on the end for, you ask? Why, what a pertinent question! Test threading the new bolts into the hot side got one stuck and the head snapped off. I was fucking pissed. I could have finished this at least 2 hours faster if I'd just followed my gut instinct and ground the unnecessary tip off my thread tap so it would chase the threads deeper. I welded the stem of the valve to the bolt, cooled it with ice, heated the turbine housing with a propane torch and it FINALLY started to budge. Gah!