Found: small external wastegate

[fspGTD]

I'm looking for a small, lightweight external wastegate for Dad's Rabbit IDI VNT project (http://www.vwdiesel.net/phpBB/viewtopic.php?t=1306&start=151)

Small packaging and light weight would be desirable and also price is a consideration.  Small bolt flanges with either weld-on or only two bolt pattern would be desirable over larger bolting flanges using more fasteners.

As it will be bolting to the EGR port off the TDI manifold, which probably has a port diameter of only about 5/8", I don't see much sense in getting a wastegate with a large diameter valve and lots of flow capacity, as it seems the average external wastegate purchaser would like.  FYI: here is a pic of the TDI turbo/manifold showing the EGR flange I would be mounting the wastegate to:

Here is what I found so far and am considering.  http://www.xs-power.com/turbo-accessories-35mm-wastegate-147psi.htm  There is one quite with a quite cheap bid price right now on e-bay I could place a bid on also...  What do you guys think?

Also, as I have not looked at external wastegates before, any experienced advice / offerings / leads would be great.  Thanks.

[vwmike]

That looks like a Tial copy. I've heard they work but wear out much sooner than the Tial wastegates. At least up until recently the Tial 35mm had the same bolt pattern as a turbonetics Deltagate, but I remember hearing of some changes. I don't really recall what it was though. Anyways, I wouldn't try and deal with Turbonetics at all if I were you. It took them like a month to ship my wastegate to me. Absolutely horrible customer service.

[fspGTD]

Thanks for the tip.  Yeah that TurboXS is a tial clone, which all use the same bolt pattern as a turbonetics deltagate.  All the smallest ones seem to use this same bolt pattern.  It's a 1.38" hole with a 2.81" bolt spacing, center to center.  The going price for a genuine Tial is about $220... pretty pricey!

[fspGTD]

By the way, I got a more accurate measurement of a TDI EGR flange.  It has bolt spacing a little bit over 2 1/4", measured from center to center.  And looking at the width of the flange, I would estimate that the hole is probably somewhere around 1" in diameter.  I think I could probably make an adapter plate and mount the small 35mm type wastegate.

[2383 GTD]

I have to fully agree here.  You do not want to go the copy route, as they all seem to have issues, the HKS copy being one of the worst.  Yup, wastegates are pricy for sure.  I have a Tial 46mm on one of my cars, which works excellent, but it is dear $$.

I might have an extra new Tial 35 or 38 around, and I will take a look for it.

Good choice with running an external, as it sounds like you will seriously exceed the vanes and turbine housings mass flow to maintain the boost you want.

That looks like a Tial copy. I've heard they work but wear out much sooner than the Tial wastegates. At least up until recently the Tial 35mm had the same bolt pattern as a turbonetics Deltagate, but I remember hearing of some changes. I don't really recall what it was though. Anyways, I wouldn't try and deal with Turbonetics at all if I were you. It took them like a month to ship my wastegate to me. Absolutely horrible customer service.

[vwmike]

Thanks for the tip.  Yeah that TurboXS is a tial clone, which all use the same bolt pattern as a turbonetics deltagate.  All the smallest ones seem to use this same bolt pattern.  It's a 1.38" hole with a 2.81" bolt spacing, center to center.  The going price for a genuine Tial is about $220... pretty pricey!

That's not even a TurboXS wastegate, it's XS Power  

If it was turbo XS it would probably be a good product.

[fspGTD]

I hear you guys re: be leary of untested generics, but at the same time it doesn't sound like you have experience with this particular wastegate.

I did some searching on the web and found reports from several on a honda tuning forum who tried the XS power 35mm wastegate and had good things to say about it: http://www.honda-tech.com/zerothread?id=942949  All the negative comments came from people who did not try it.  The only negative direct report I did find on the internet related to this particular wastegate model when when it was not matched properly for it's flow requirements.

Since the application I have is not particularly demanding in terms of wastegate flow requirements (compared to a larger motor and/or a non-VNT turbo) and the conservatively fueled diesel will also not need extremely high heat capabilities, plus I have the intake manifold blowoff as a safety device should the wastegate fail, I figure I have as good a chance as any as being able to get away with the cheap brand.  So I decided I am going to risk it and I just ordered the XS power 35mm - for $130 shipped.  (It saved about $90 compared to a genuine Tial.)  Pic:


Hopefully it will arrive in time for me to begin the install early next week.  I will give it a thorough inspection when it arrives, and will report to the group on what I find, and also how it ends up working out!

[fspGTD]

The XS-power / ssautochrome wastegate arrived.  Wow - came with quite a few extras... flanges, gaskets, dump tube, mounting tube, nuts and bolts... that's a lot of stuff for $130 shipped!  



I was impressed generally with the quality.  It featured polished stainless tubing pieces, thick flanges, and the tubing was welded to the flange with some great looking TIG beads.  The wastegate looks like the outer can might have been assembled a little quickly (one of the bolts wasn't quite tight... maybe that was the guy who swapped the spring before shipping it?) but disassembled it and inside, it looked great.  I noted some sort of threadlocker or sealant on all the internal fasteners, and generally inside it looked well designed and put together.

I got the green spring.  According to Tial's color sizing, that is spec'ed at .9bar / 13 psi.  Assuming that's what this is since it's a Tial clone, that pressure setting seems about perfect!    The spring has a long free-length (enough that there is a pretty decent pre-load on the can making it hard to start the bolt threads in!) but that is a good thing from a design perspective because it will make the wastegate react very quickly.


This has a lot of generously sized, expensive austenitic stainless and aluminum parts going into it.  About the only thing magnetic that I found on it was the spring!  The quality of manufacture of the components is very high.  Nicely machined pieces and cast stainless housing all look great.  The action of the valve is nice and free.  But I wonder if there is supposed to be some kind of lube on the shaft... if anyone can help me with a recommendation here, it would be great, it looks dry from the factory (but maybe that's how it should be.)

Note the nice looking high temp silicone diaphgram:


Note the separate replaceable valve seat (installed).  The flow capacity of this thing looks great, and like way more than I am going to need.  General impression was of a very heavy duty unit.  I can't believe this style of wastegate is the smallest one on the market.

[fspGTD]

To try and test the opening pressure of the wastegate, I hooked up my pressure brake bleeder to the wastegate and pumped it up.  Well after I got upwards of 5 psi in there, the air started leaking out which I determined was coming out around the valve stem.  I wasn't able to pump fast enough to get the pressure past about 10 psi, or high enough to make the valve open.

Anyway, my first thoughts are that this air bleed is by design to help cool the wastegate valve.  Do any of you other guys that have external wastegates know if they are commonly designed like this?  I guess thinking about it more, the internal 1.6lTD Garrett wastegate has a boost pressure bleed from it's wastegate diaphgram can, which bleeds through a rifle-drilled portion of the wastegate valve stem coming out inside the valve guide, which is to help cool it.  So I am thinking this is probably by design.

I guess due to the air flow, I'll hook this up using a pretty decent sized vacuum line (1/4" ID was recommended in the instructions) and tap it in to the manifold separately from the other vacuum connections (for the boost gauge, VNT control, and fuel enrichment).