Surge, BOV not holding or boost leak (video inside)

[AlphaVision]

So I have this issue and the car seems not too fast as before. I have swapped the K272s with stock. Actually the exhaust is a 260 degree (NT stock cam). This issue was present with the K272s as well but it gets wors or at least I think it does.

Can you identify the problem by watching this video?

Boost issue - YouTube

 

[92AWDHX40]

Could be a boost leak, do one and see what you find.

 

[josh1095]

it sure does sound like bov fluttering. im a bit noobish though

 

[turboglenn]

Looks like surge to me, the BOV shouldn't flutter under WOT it should either leak or not. Surge occurs when the turbo pushes more air than the engine can take in early on.. try this.. drop into 2nd from third at say 40-45MPH and go WIDE OPEN, a lot of times that';s a way to tell if it's surging if this doesn't happen if you start at a high RPM and go WOT

It is mainly dfrommaking more boost/airflow at a lower RPM where the engine can't take in the air because VE is low. My BB 57 trim surged BAD while the same turbo in journal bearing didn't because it spooled later on in the RPM range.
Although a 68hta shouldn't surge that bad unless it'e that exhaust cam. I'd work on removing restriction in the engine like the 260 cam.. also if you ahve adjustable cam gears redusing some overlap will let more air into the engine and solve this also.. My favorite settings for great power and an awesome idle is to put it at +4 exh. and -4 intake, with less overlap you ge tmore exhaust out leaving an empty chamber for the incoming air to fill. Turbo cars are the opposite of NA cars and don't like overlap at all unless you're happy tooling around at under 4k RPM at best

overall the surge isn't that bad, i's say some minor changes or cam degree work wil solve it

 

[AlphaVision]

Thanks Glenn. I will try to degree the cams as you suggested. I know the 68HTA is surge prone, but I am noob-ish to the turbo cars and wasn't sure. The surge wasn't that bad with the K272s but it was there. However those cams were overkill and I was afraid to degree them so i decided to downgrade and stick with the stock ones while I fix all the small issues.

So, thank you and hopefully will solve the issues