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Wastegate removal
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bureau13  



Joined: 07 Sep 2017
Posts: 239
Location: South Florida

PostPosted: Mon Apr 27, 2020 3:44 am    Post subject: Reply with quote

So I managed to get the wastegate out, I changed the spring on the Tial to something in the stock range and now I'm putting it back in. Unfortunately, I've hit a snag: The pipe that goes from the discharge side of the wastegate and plumbs back into the exhaust doesn't fit. You can see what I mean from the photos I've linked. The flange mates up fine, but that circular ring/pipe edge/I don't know what you call it that needs to slip inside the wastegate flange opening doesn't fit. Interestingly enough, it does fit into the opening in the valve seat for the input side of the wastegate, but that's not particularly helpful.

Is this normal? The F46 is supposed to be a drop-in replacement, so either it's not, really, or something is off with either the wastegate or the pipe.

https://photos.app.goo.gl/uEYXSs2ksQ6cACh77
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1982 931
1986.5 Silver 928S
2007 Hummer H3 (Daily Driver)

Past lives (I miss them all):
2004 RX-8 (Wrecked)
1993 RX-7 (Sold)
1987 RX-7 Turbo II (Sold)
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bureau13  



Joined: 07 Sep 2017
Posts: 239
Location: South Florida

PostPosted: Mon Apr 27, 2020 6:17 am    Post subject: Reply with quote

Of course this pipe fits perfectly into the stock wastegate, so I took a look at that (see third picture that I just added to the above link) and it appears that the opening has been machined such that it's wider at the surface so that bit of pipe can fit in there. It's not totally clear in the photo but that is what it looks and feels like. So do you have to machine the opening to the input side of the wastegate? Not sure that's a great idea, and I've never heard of anyone doing that.

Another possible (temporary?) solution is get a dump pipe that just vents to atmosphere, but then the wastegate is only held in place by the j-pipe (no bracket to attach to the body like stock, of course it's a good bit shorter and lighter) which doesn't seem like a great idea either. Plus, I've heard that sounds godawful...
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1982 931
1986.5 Silver 928S
2007 Hummer H3 (Daily Driver)

Past lives (I miss them all):
2004 RX-8 (Wrecked)
1993 RX-7 (Sold)
1987 RX-7 Turbo II (Sold)
1985 RX-7 GSL (Stolen)
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chuck21401  



Joined: 20 Feb 2005
Posts: 240
Location: Annapolis, MD

PostPosted: Mon Apr 27, 2020 9:20 am    Post subject: Reply with quote

bureau13 wrote:
So I managed to get the wastegate out, I changed the spring on the Tial to something in the stock range and now I'm putting it back in. Unfortunately, I've hit a snag: The pipe that goes from the discharge side of the wastegate and plumbs back into the exhaust doesn't fit. You can see what I mean from the photos I've linked. The flange mates up fine, but that circular ring/pipe edge/I don't know what you call it that needs to slip inside the wastegate flange opening doesn't fit. Interestingly enough, it does fit into the opening in the valve seat for the input side of the wastegate, but that's not particularly helpful.

Is this normal? The F46 is supposed to be a drop-in replacement, so either it's not, really, or something is off with either the wastegate or the pipe.

https://photos.app.goo.gl/uEYXSs2ksQ6cACh77



So if you add the gasket (32) in there...no help?



This is the best pic I could find of my WG looking from the side.


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chuck21401  



Joined: 20 Feb 2005
Posts: 240
Location: Annapolis, MD

PostPosted: Mon Apr 27, 2020 9:35 am    Post subject: Reply with quote

Found this pic.


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bureau13  



Joined: 07 Sep 2017
Posts: 239
Location: South Florida

PostPosted: Mon Apr 27, 2020 2:40 pm    Post subject: Reply with quote

The gasket is very thin, so no help in this case. I removed it for the photos just to avoid obscuring what I was trying to show.

Those pics of your wastegate show what I was talking about in terms of the "machining" or whatever of that opening. I suppose I could take it somewhere and have that done to the Tial, but I'm hesitant to do so. Why is this considered a drop-in for the 930 wastegate? Does the 930 not have the same issue?

Unfortunately, finding someone who is using a Tial on a 931 has been almost impossible. I guess I understand the argument that it's no performance benefit and is much more expensive that repairing the stock one, but in my case I got the Tial for about the same price or less than a rebuild kit. Plus, it's lighter
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1982 931
1986.5 Silver 928S
2007 Hummer H3 (Daily Driver)

Past lives (I miss them all):
2004 RX-8 (Wrecked)
1993 RX-7 (Sold)
1987 RX-7 Turbo II (Sold)
1985 RX-7 GSL (Stolen)
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Mike9311  



Joined: 14 Dec 2004
Posts: 834
Location: Chicago-ish

PostPosted: Mon Apr 27, 2020 10:58 pm    Post subject: Reply with quote

Are you able to measure the diameter difference? If so, is it a lot or just a tad off?
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chuck21401  



Joined: 20 Feb 2005
Posts: 240
Location: Annapolis, MD

PostPosted: Tue Apr 28, 2020 1:41 am    Post subject: Reply with quote

Not to complicate matters, but when I search for images of the Tial F46, some seem to have the ridge.

https://www.ebay.com/itm/381933792273
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bureau13  



Joined: 07 Sep 2017
Posts: 239
Location: South Florida

PostPosted: Tue Apr 28, 2020 3:14 am    Post subject: Reply with quote

Re: Measurements. It seems close. I'm still looking for my caliper to measure it properly, I seem to have not put it away last time

That picture is interesting...that definitely looks like it has the recessed area machined in. I wonder what the difference is?

There was a version of this wastegate that was the F46P, but supposedly the only difference was some of the cooling fins were ground down so the body was thinner and wouldn't rub in certain 930 applications. It does make you wonder if there were other changes, however. I can't tell from that picture if that's an F46P or a standard F46 like mine, however.
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-----------------------------------------
1982 931
1986.5 Silver 928S
2007 Hummer H3 (Daily Driver)

Past lives (I miss them all):
2004 RX-8 (Wrecked)
1993 RX-7 (Sold)
1987 RX-7 Turbo II (Sold)
1985 RX-7 GSL (Stolen)
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Fasteddie313  



Joined: 29 Sep 2013
Posts: 1912
Location: MI

PostPosted: Tue Apr 28, 2020 5:05 am    Post subject: Reply with quote

I'd prolly just break out the angle grinder and grind the protruding pipe off of the dump pipe until it is then just a flat flange..
Have you considered that?

That's the low/no pressure side of the exhaust, no real pressure to leak, and wouldn't much matter anyway..

Use some red permatex on both sides of the gasket if you really wanna be sure..
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bureau13  



Joined: 07 Sep 2017
Posts: 239
Location: South Florida

PostPosted: Tue Apr 28, 2020 2:22 pm    Post subject: Reply with quote

That's basically what the Tial tech support guy said when I emailed him, so that is the current plan.
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-----------------------------------------
1982 931
1986.5 Silver 928S
2007 Hummer H3 (Daily Driver)

Past lives (I miss them all):
2004 RX-8 (Wrecked)
1993 RX-7 (Sold)
1987 RX-7 Turbo II (Sold)
1985 RX-7 GSL (Stolen)
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Carrera RSR  



Joined: 08 Jan 2010
Posts: 1970
Location: Somerset, UK

PostPosted: Tue Apr 28, 2020 8:51 pm    Post subject: Reply with quote

Did you buy the Tial from an authorised seller. There are many fakes out there. Not saying yours is, but itís a known problem. Could be why you see some with fire ring recess and some without? Just a thought
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Then www.924board.org/viewtopic.php?t=31252
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chuck21401  



Joined: 20 Feb 2005
Posts: 240
Location: Annapolis, MD

PostPosted: Tue Apr 28, 2020 10:01 pm    Post subject: Reply with quote

re: idea to add mount/support (Tial doesn't have mounting bracket on top).

Check out the bracket in this thread on MOTANUL's car:
http://www.924board.org/viewtopic.php?t=43986&postdays=0&postorder=asc&start=90

See this service bulletin; looks like more support was added as part of mods to the turbo and exhaust. I worry that cutting off that pipe & not having a mount at the top of the WG loses support. Maybe something like this would help, assuming you can find the kit or fabricate something similar. Part number is 00 043 023 00; appears to be made out of unobtainium.




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bureau13  



Joined: 07 Sep 2017
Posts: 239
Location: South Florida

PostPosted: Wed Apr 29, 2020 10:52 am    Post subject: Reply with quote

Re: Tial vendor

I actually got mine used, so who knows where it originally came from? I'm not sure how to tell the difference.

Re: bracket

I'm not sure if what (if anything) I will do about that, but...that just looks odd. Hmmm...
_________________
-----------------------------------------
1982 931
1986.5 Silver 928S
2007 Hummer H3 (Daily Driver)

Past lives (I miss them all):
2004 RX-8 (Wrecked)
1993 RX-7 (Sold)
1987 RX-7 Turbo II (Sold)
1985 RX-7 GSL (Stolen)
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bureau13  



Joined: 07 Sep 2017
Posts: 239
Location: South Florida

PostPosted: Wed May 13, 2020 9:00 am    Post subject: Reply with quote

So I gave my bypass pipe to a friend who has the tools to do this sort of thing, and he ground off that ring/lip/whatever so that it was flush with the mounting flange. FYI it appears to be a pressed-in piece, which you can see now. Anyway, I got it all bolted in there, I have no bracket support right now but it's not nearly as heavy as the stock wastegate, and seems in there solidly. I am getting some possible rattling sound under acceleration, not sure if that's where it comes from or not, but I'll keep an eye on it.

I do now have rock solid boost at stock (domestic) boost levels, which is both great (because it's safe) and sucks (because it's slow). But it's better off the jump because it's not bogged down wasting air out the old diaphragm now at least, and once I get things sorted I will raise the boost a bit.
_________________
-----------------------------------------
1982 931
1986.5 Silver 928S
2007 Hummer H3 (Daily Driver)

Past lives (I miss them all):
2004 RX-8 (Wrecked)
1993 RX-7 (Sold)
1987 RX-7 Turbo II (Sold)
1985 RX-7 GSL (Stolen)
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chuck21401  



Joined: 20 Feb 2005
Posts: 240
Location: Annapolis, MD

PostPosted: Sat May 16, 2020 4:16 am    Post subject: Reply with quote

Back on road!

How about running euro boost level by using a manual boost controller.
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