Hey guys,

Would love to pick everyones brain. I decided to stick with my G18s and just turn up the juice, but I think I've got a boost leak-- let me know if this makes sense.

Went from AT to MT with an HKS SSQV, there is no adjustment on an HKS (famously) but it was the only BoV I could really use with my AT and not stall at low RPM.... Now I was stalling at Low RPM when I moved to a MT.

We drilled a VERY small (3/16" ish) hole in my throttle body, and it cured my car diving for 300 RPMs everytime I hit the clutch (and ultimately stalling my car in a lot of situations).


So recently: I upgraded my wastegate springs, took the OLD HKS SSQV off and put a Tial 50MM with appropriate spring. I could only run about 16.5 PSI on the dyno and made 589 torque and about 575 HP ( No dyno sheet to show you)... Now when I drove it, the BoV sound was delayed by fluttering / surge.

I THINK, that hole in my TB is messing with my vacuum and boost at high boost, and now that my BoV has adjustability, I can use that instead of a hole in my TB.

Thoughts?

 

Your car should be in full boost at higher RPMs so the hole in the TB shouldn't have an effect.
Is it possible that the springs you upgraded to are too stiff? and what makes you think it's surge.

 

The part where I hear surge, makes me think that.

 

Nice......
My guess would be you're maxing out the turbo then or working it outside its efficiency range.