Tial 38mm wg

[shadow325]

Does anybody have an external wastegate venting to atmosphere? If so does the valve leak a small amount before hitting boost while the engine is under load? My tial didnt for the first few days but now there is a really small exhaust leak past the valve that makes the car sound like a boat when the engine is loaded at low rpms. It is really minor but I was just wondering if it is normal.
Thanks -Colin

[swartz]

might be leaking from the gasket or ring that is under the wastegate

[iflytii]

If you are not using a boost controller it very well could be opening slightly before hitting full boost. That's pretty normal I think. You could also have a leaky gasket between the wg and manifold. Mine keep failing there... ](*,)

[screaming_bmwe30]

definately the gasket. IMO...gaskets are worthless. I sealed EVERYTHING with That Copper high temp silicone. And just mated metal to metal. Didn't leak a bit when i did that, and surprisingly...my in cabin noise level went from seemingly open downpipe type noise levels to sounding like i had 3 mufflers inline. It sounded really good with everything sealed up.

Here is a pic of the rtv i used. Make sure you assemble with that stuff wet.

Oh yeah....and i was running an open downpipe, with the 524td manifold, so i was running a similar setup.

http://ace.imageg.net/graphics/product_images/pACE-984936dt.jpg

[///ARINUTS...]

sorry to go off topic here, but I got a question.

I have a 35mm wastegate, which is pretty much identical to the 38mm one, except, of course the valve is 3mm smaller, with a smaller fire ring.

Ithought I read somewhere that someone got the 40mm valve with the fire ring and installed it into the smaller housing, the 40mm isn't available in a 2 bolt housing, only the bigger 4 bolt. So is this possible? can we upgrade the size of the WG valve?

I'm pretty sure I can use the 38mm, as it's so close to the 35mm, but the 40mm I'd like to make sure of.

Also, Where can we get these WG parts?

[screaming_bmwe30]

sorry to go off topic here, but I got a question.

I have a 35mm wastegate, which is pretty much identical to the 38mm one, except, of course the valve is 3mm smaller, with a smaller fire ring.

Ithought I read somewhere that someone got the 40mm valve with the fire ring and installed it into the smaller housing, the 40mm isn't available in a 2 bolt housing, only the bigger 4 bolt. So is this possible? can we upgrade the size of the WG valve?

I'm pretty sure I can use the 38mm, as it's so close to the 35mm, but the 40mm I'd like to make sure of.

Also, Where can we get these WG parts?

Well...considering the 38 and 40 are 3 and 5mm larger respectively...you will have to bore the valve seat out, and hope that the valve assembly is exactly the same. Oh...and then the fact that the size of the valve port, and outlet where the exhaust flows through will have to be ported out, to take advantage of the larger valve.

All in all...it's probably not possible without expensive machining, and it probably won't make a difference. a 35mm should control boost, especially if running a restrictive, hi pressure exhaust manifold (easy exhaust release out the wastegate)

[shadow325]

I just removed my wastegate and the gasket is turned to ash. I'll probably use that copper gasket maker like screaming said. - thanks

[screaming_bmwe30]

I just removed my wastegate and the gasket is turned to ash. I'll probably use that copper gasket maker like screaming said. - thanks

same thing happened to me.....twice :) you could actually use paint or anything to seal in the little pores in the two mating surfaces. I used that silicone, because my buddies all use it with good results, on turbo DSM's etc. The only other gasket i would use would be the SS sheet gaskets, but you can only use them once, since they are compression gaskets, and since they are hard to just get your hands on in a flash, using no gasket is the obvious choice. No high hp ride around my area uses gaskets though, they just have machined flanges, with a sealant.