bonus12

I have this wonderful piece of hardware, the Tial 38mm, along with the adapter plates, but I don't run a boost controller. My understanding is that I will let the top port vent to atmosphere by not connecting it to anything. And I will connect the side port to the boost line.

It should look like this, I'm thinking.
Is that correct? Installing this soon.
Thanks

bonus12

So I installed the wastegate. Boost seemed to build really quickly and the pressure blew the intake hose off the throttle body somewhere approaching 20 psi. I'm usually at 17-18 psi max. I know I have the wastegate on correctly, I know that much. I attached the hose from the cycling valve to the side port, and left the top port open, as I don't use a boost controller. Unfortunately, info is really sparse on using a tial without a boost controller. I use a banjo bolt restrictor, instead. So I'm hoping someone can confirm I probably just need to switch the vacuum line to the other port. I wasn't expecting that but I don't see any other options.

Interestingly, when the intake hose blew off the throttle body, the hose jammed the throttle cam wide open, which seemed to help me limp to a parking spot to secure the hose back on. I think that hose clamp, which was a little too lose, acted like a safety.


ETA: I have to say, the tial 38mm with the adapter plates was an odd install for one reason. On one of the adapter plates, the 4 bolt holes were threaded, which is fine, but the holes of the exhaust pipe mating surface also had threaded holes, meaning the bolt going through does not "pull" them together as it tightens. I had to mate the sections first and then thread the bolt through, which is not ideal for a perfect seal. I think I'll have to drill those threads out because I don't want any leaks.

944M3

I have a 38mm Tial.

What size spring are you using?

To me it seems that the banjo bolt restrictor is not allowing enough pressure to “help” in opening the actuator. Which might mean your spring is to big. All this contributes to the actuator not opening and why you saw 20psi. Be careful.

It took me a while to truly understand how a dual port wasgate works. It’s somewhat counterintuitive. I’ve read bad descriptions on this board even. I watched as many YouTube videos on dual port as I could find. Again, it took me several videos before the light bulb came on.

I would recommend confirming your spring weight. I would also remove the banjo bolt restrictor.

A dual port will work with a single reference but it’s really meant to run with a manual or electronic boost controller. That’s where it shines.

bonus12

I got one with a 0.8 Bar spring. I'm thinking I'll do what you said and remove the restrictor, ie go to stock boost level, after fixing up a few other things in there. The unit is from a reputable source so there's that.

944M3

Really good video.

Keep in mind, by removing the restrictor you’re not really going back to stock boost. You are providing a more accurate reference of the psi pressure in the intake or boost to the wastegate. This reference, along with the exhaust pressure, helps the actuator open. A boost controller helps you fine tune the reference to better control when the actuator or wastegate piston opens.

All that being said and for full disclosure, I deleted my cycling valve and replaced the stock wastegate as soon as I purchased my car. So I have no clue how or what the cycling valve does in this situation. Hopefully someone else can chime in.

bonus12

I am aware that the cycling valve receives information from the KLR about when to open or close. In normal open mode, the cycling valve takes turbo discharge and reroutes it back to the turbo inlet via the J boot. If the KLR gets concerned, or there is failure, including unplugging the CV, the valve takes the turbo discharge but this time sends it to the wastegate to do what you described in conjunction with exhaust pressure. This forces the wastegate to let the excess pressure out the tailpipe.

The banjo bolt setup (which can be adjusted based on the jet size), and the boost controllers (which are adjustable with a ****), therefore send less pressure to the wastegate when the KLR thinks its time to time to dial down the pressure, which makes the turbo build more pressure. This is what you said. This is when chips are needed.

Thanks for your posts. I see what you mean about not going to stock boost. With the stock banjo bolt, I think it's maxing out at 15 psi now with the tial, but I am testing it carefully. I think the hose coming off was because I re-positioned that hose a couple months ago, so the hose clamp had seated loosely. Everything may be in order, after all. I was just not expecting the boost to come on so much more suddenly.

I might unplug the cycling valve to see what exhaust pressure the new wastegate spring holds on its own. Clark's Garage states the stock wastegate on a stock car holds 1.2 BAR while unplugged. Would be interesting to test the tial once I have everything settled.

bonus12

Looking at this diagram, I'm not sure how dual port mode works other than apply a lower differential pressure across the diaphragm, therefore causing it to open even later. It's like increasing the spring rate. I think the banjo bolt restrictors aren't as desirable but they are only about $1.





The 3 on the right side override the cycling valve completely, so people can remove it. I don't have one but apparently there is a pressure threshold. The one the left works in conjunction with the cycling valve to restrict all turbo discharge air from touching the wastegate until the chips tell the cycling valve to open.
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