Hey Folks,

Does anybody have any experience with adding a wastegate helper spring to the stock wastegate. I have a bnr stage2 hybrid and and can't seem to get any boost past 10psi.

I've installed a manual boost controller and turning it up higher doesn't have any effect.

I thought my bov was leaking so I added a washer to it and that had no effect. Made it sound higher pitched and not go off under vacuum as much.

Any ideas?

 

I thought the BNR stage 2 has an aftermarket adjustable wastegate actuator?

 

if it does i haven't seen it. I talked to bryan and he said he can sell me a different wastegate that has a base spring of 12psi.

 

Remove the vacuum line to the wastegate (temproarily block off the open ports) and see if it's physically capable of boosting past 10 psi before throwing parts at it.

 

yeah, it's threaded so you can preload the wastegate actuator just like the HKS adjustable unit is.

 

just went and looked. It does have a threaded rod on there. Do I want to shorten the rod or make it longer?

 

i have done the helper spring mod several times
-- and currently use a HKS adjustable ( shorter = more boost ) pot,, WITH a helper spring

( the extra/dual spring helps to smooth out operation as well as increase boost,, unlike pneumatic bleeds that can bring unwanted spike/overshoot/overcontrol effects )

the install in the car ATM didnt bring up any decent pics,, so i took some shots of the turbos i have in the shed instead to illustrate the various methods of adding a spring


the method involves drilling a hole in the pots edge ( not in the diaphram part )
and another at the end of the shaft
( or alternately add a plate or nut at some point along the shaft )

-- the ones with plate ( many adjusting holes ) or the nut are intended to run the spring across a 45 angle as the hypotinous
(so the springs effect is not quite as its rating )

the ones with hole tapped into the shaft near the C clip are intended to use a spring that is installed ALONG ( over ) the shaft
-- that is the spring works at a true rating to supplement the original



( spring not shown )
the nut added to shaft and hole tapped into the can edge
-plainly the shaft has rotated 180 to its intended position


( springs not shown )
this one is universal,, originally built to take the spring wound along the shaft
( note holes in can edge )
later it had the small alum bracket added and the spring run as hypotinous
( the original added spring failed and this was added in car to fix )



( springs not shown )
lower can has a hinge plate welded to the shaft ( in preference to a nut )
to provide many settings
the upper can used the original spring along shaft technique

NB
s5 can/arm with the kink is much better suited to spring along shaft technique due to the kink

PS
-- if welding anything to the shaft ( plate or nut or adjuster or shorten/lengthen )
you need to submerge the can into a bucket ( with shaft out ) before you weld
( obviously the heat can ruin the diaphragm )

 

from what I have gathered if you shorten the rod this will increase the base boost pressure. I'll test this out tomorrow if it's not raining.

 

I shortened the rod up a bit this morning and it didn't seem to have any effect I didn't max it all the way out though. I will try capping off the wastegate line to see what that does.

 

shortened the rod up even further and still no change. I need to fix an issue with the throttle getting stuck on the floor before doing anything else (think its getting caught on the carpet) I data logged a run and it looked like it was trying to go to 11psi on my boost gauge but I had to keep my eyes on the road not on the gauge.