2G Major overboost issue

[Ramsey91]

Alright so I’m having major over boost issues and I’m kind of stumped right now. I’ve tried two 38mm wastegates and a 44mm thinking maybe 38mm was too small, but same issue. I thought wastegate may be stuck but considering I’ve gone through three new ones it’s doubtful. Gonna bench test them though to see what they are opening at.

I’m running a gtx3071 on SD and bypassed ebc by going straight from the compressor housing to the bottom port and top port vented. Also checked for leaks but I haven’t found any. I’m gonna boost leak test it again and spray everything with soapy water to see if there’s any small leaks.

What else should I be looking for? I know positioning and flow is important as well so maybe this is the issue? I can post pics/video of setup if needed.

I’m having the car remote tuned by Ricky at rixracing and he’s been helping me but I feel bad constantly asking him questions considering how busy he is. I’ve also been doing research but wanted to ask to get some more input.

I should also mention I’m just trying to see base pressure so I can start tuning. I’ve used a 9psi spring combo, 14psi combo on 38mm and 11psi spring combo on the 44mm. I saw almost double base on first attempt and let off immediately. The other attempts have been acting the same but I've been letting off as soon as it goes over. Boost starts building at 4krpms and starts to really let go closer to 5k.

 

[pauleyman]

Where is the gate mounted? How is the outlet of the gate plumbed? To atmosphere or recirculating?

 

[Vegas Smith]

There are only 4 things that it could really be:
1) Your wastegate setup can't bypass enough air for you to control boost--seems doubtful but I have no idea what your setup looks like
2) boost controller is bad
3) boost control lines are not installed correctly
4) Tune is setup incorrectly

Give us the details on 2-4

 

[jdxnc]

What sorta boost level are you aiming to run? You said you saw almost double the base, I mean that's not really terrible. I did my base pull on my Fueltech at spring pressure, which turned out to be 26 psi, with some care you can make it work.

 

[Ramsey91]

Where is the gate mounted? How is the outlet of the gate plumbed? To atmosphere or recirculating?

Here’s a photos of where it’s mounted. It’s going to atmosphere.

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[Ramsey91]

There are only 4 things that it could really be:
1) Your wastegate setup can't bypass enough air for you to control boost--seems doubtful but I have no idea what your setup looks like
2) boost controller is bad
3) boost control lines are not installed correctly
4) Tune is setup incorrectly

Give us the details on 2-4

I bypassed the boost controller though going straight from bottom port of wastegate to compressor housing. All installed correctly from multiple diagrams I’ve been given. Everything that was setup for tune looked correct as well. I’m not on my computer at the moment but I’ll post some pics in a bit.

 

[DSMPT]

Edited : Sorry didn't see the pic very well.
Aren't you actually feeding the boost pressure to the coolant ports and blocking off the lower port?

 

[Ramsey91]

What sorta boost level are you aiming to run? You said you saw almost double the base, I mean that's not really terrible. I did my base pull on my Fueltech at spring pressure, which turned out to be 26 psi, with some care you can make it work.

Would like to go for around 20psi but I feel like that shouldn’t be happening. Running the lines from the compressor of turbo to bottom port of wastegate I should only see that base spring pressure. What psi springs did you have in?

 

[pauleyman]

Edited : Sorry didn't see the pic very well.
Aren't you actually feeding the boost pressure to the coolant ports and blocking off the lower port?

I concur that doesn't look right.

 

[Vegas Smith]

Agreed, looks like you're using the coolant port per Racetronix diagram. Need to switch to this port:

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[Ramsey91]

Agreed, looks like you're using the coolant port per Racetronix diagram. Need to switch to this port:

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No those are both air ports for top. They give you multiple places to put your air ports. Also labeled above each hole are air and h2o so it’s impossible to mix up unless you don’t read it.

 

[Ramsey91]

Edited : Sorry didn't see the pic very well.
Aren't you actually feeding the boost pressure to the coolant ports and blocking off the lower port?

It’s the correct port. They are labeled above each hole, and coolant and air are different sizes so it’s impossible to mix up.

 

[Ramsey91]

I concur that doesn't look right.

It’s the correct port. The one that doesn’t have anything blocking it is the coolant port

 

[Vegas Smith]

All be damned, I looked all over their website and couldn't find a single manual/instruction guide.

 

[Ramsey91]

No those are both air ports for top. They give you multiple places to put your air ports. Also labeled above each hole air and h2o so it’s impossible to mix up unless you don’t read it.

All be damned, I looked all over their website and couldn't find a single manual/instruction guide.

Nope me neither which sucks, but I’ve been communicating with the company to try and get some help. It’s all hooked up correctly. I’m literally the first person to have this issue with them. Wastegate looks extremely well built and I’ve torn the wastegate apart and nothing wrong with it.

 

[pauleyman]

I assume you heard that sucker when you got into boost?

 

[Ramsey91]

I assume you heard that sucker when you got into boost?

Only thing I can hear is the exhaust cause it’s a side exit

 

[DSMPT]

It’s the correct port. They are labeled above each hole, and coolant and air are different sizes so it’s impossible to mix up.

That's why I edited after I saw the pics you uploaded. But a wastegate function is very simple. I would still double check all installation.
Did you check if the the wastegat port opens by applying compressed air? Are you 100% sure the diaphragm and spring move smoothly?

 

[Ramsey91]

That's why I edited after I saw the pics you uploaded. But a wastegate function is very simple. I would still double check all installation.
Did you check if the the wastegat port opens by applying compressed air? Are you 100% sure the diaphragm and spring move smoothly?

I’ll double check everything in the morning but no have not tested yet. I’m gonna go buy a regulator so I can pressure test each of them and see if they are opening properly. Just seems unlikely all three would have issues but I mean anything is possible.

 

[DSMPT]

I’ll double check everything in the morning but no have not tested yet. I’m gonna go buy a regulator so I can pressure test each of them and see if they are opening properly. Just seems unlikely all three would have issues but I mean anything is possible.

Maybe you have an issue with the boost feed since you tried two wastegates.
Since you mentioned that you took the boost feed directly from the compressor housing, did you confirm that where you put a fitting on the compressor housing is surely seeing the boost? I know this sounds very basic and unlikely, but I have seen a person that put a boost feed fitting on mounting bolt hole. Mentioned this just to eliminate a possibility.

 

[Ramsey91]

Maybe you have an issue with the boost feed since you tried two wastegates.
Since you mentioned that you took the boost feed directly from the compressor housing, did you confirm that where you put a fitting on the compressor housing is surely seeing the boost? I know this sounds very basic and unlikely, but I have seen a person that put a boost feed fitting on mounting bolt hole. Mentioned this just to eliminate a possibility.

I am not 100% sure it is. It was pre-tapped for a fitting so I would assume so but how can I check if it is seeing boost? I was also thinking eliminating the rubber o ring on the fitting and using sealant on it instead.

 

[DSMPT]

I am not 100% sure it is. It was pre-tapped for a fitting so I would assume so but how can I check if it is seeing boost? I was also thinking eliminating the rubber o ring on the fitting and using sealant on it instead.

I meant, is that pre-tapped hole originally for boost source? Isn't that to attach something or for a speed sensor?

 

[Ramsey91]

I meant, is that pre-tapped hole originally for boost source? Isn't that to attach something or for a speed sensor?

Ahhh my apologies I see what you mean. I’m pretty sure it is for a boost source but I could be wrong. I’ll have to ask the company I got it from

 

[DSMPT]

Ahhh my apologies I see what you mean. I’m pretty sure it is for a boost source but I could be wrong. I’ll have to ask the company I got it from

Yeah just wanted to make sure if the hole is completely drilled and passed through until inside the compressor housing.

 

[99dsmer4g63]

FWIW I battled this about a year ago. My issue ended up being the gate not opening enough.

I was over shooting target boost by a lot.

I took my springs out to verify if it was a my holes aren’t big enough problem. To my amazement I could barely build boost.

I ended up removing the gate and using the tee from the BLT tester I made. Air compressors have built in regulators fyi. Then I could see exactly where it would crack open and how far it would open.

For some reason my 19psi spring would not let the gate fully open. Ended up using a 15 psi spring and ended up fixing the issue. I use an EBC now so I can hit my higher target.

I encourage you to bench test it.

-Daniel