Thread: Wastegate too stiff???

Hey guys.

I've been driving my car around the town for the time being. I have my boost controller completely turned down. No air flow.

I have been boosting to 20PSI plus. The problem is that I have checked the waste gate door and it fluctuates. My waste gate is new from ATP turbo. Its the 6 psi waste gate, So I have no Idea. Its an adjustable wastegate rod which I only screw on lightly. I've taken off the waste gate, and Hung the waste gate and attached a 15lbs weight to it and it only moves a little bit. But with 20-28lbs added hanging from it, it extends fully. I would think that a 6 lb spring wouldn't need to have 20-28 lbs hung from it to open.

I'm am kind just trying to figure it out. But I cannot flat foot my car because she'll continue to spike. I have extended the rod in order to clear the block. Any thoughts? Ideas? or past experiences?

Just a thought, have you tried running it without the boost controller hooked up?

Connect the wastegate vac line to a good source, removing the BC from the picture. Adjust your via this vid.
if it starts working correctly reconnect the BC to rule it out as the point of failure.

Yeah, I understand taking off the bc. I guess it could still bleed and pressurize te diaphragm.

When I installed it. I adjusted the preload as demonstrated above. This spring is pretty stiff in this diaphragm. I feel too stiff but I haven't felt many other wastegates.

20psi spike, maybe? No way that 6psi wastegate is holding 20psi to redline. The only way I can fathom that is they sent you the wrong one or the one they sent you has the wrong spring in it or it has malfunctioned.

Also, when you put the wastegate arm on the flapper pin, it should be placed with minimal tension. In other words, it needs just enough tension to keep it on the pin. It should be 'snug' but no more than that. Don't over-tighten the wastegate arm or you WILL overboost. For a 20psi spike, you must have that thing really tight or the wastegate isn't seeing a boost source from your engine when you start boosting and it's like taking the wastegate vacuum line off which just tells the turbo to spool up as much as it can with no limits.

I'd check wastegate arm tension and confirm the wastegate is seeing a boost source. You can confirm the wastegate is even working at all by hooking up the wastegate vacuum line to a basketball pump and you should start to see the wastegate arm push out of the diaphragm as you pump it up.

-G

This happened to me on my 5psi wastegate on a brand new GT28r, the issue turned out to be the wastegate door not opening easily.

what was wrong with your wastegate flapper? The thing comes up just turning the turbo upside down on my car?! Was the hinge messed up?

It looks like it yeah, it was not opening easily, I figured it was because it was brand new. After running it for a few days, removed it and saw that it had some stress cracks. Shame for a brand new turbo... luckily I had a spare jet coated used housing though.

Thank you for the input guys! I did preload the adjustable arm with 3 full revolutions. I created a bench tester out of some simple fuel line I had laying around and a T barb fitting from lowes. I used a cheap tire pressure gauge from auto zone.

I confirmed that the waste gate was operating normally with the correct pressure.

I buttoned everything up and pressure tested my MBC (blox) and then ultimately realized my stupidty. It's a one way valve I simply had the lines crossed. I connected the correct way, and fully opened the valve and took her out and got 7 psi consistently across the rpm range

Problem solved. Glad I didn't have to fab anything or send the waste gate back
Thanks for the input guys!

-Josh

Ya that'll do it. No boost source = happy turbo but also = dead engine

Glad you got it fixed.

-G