c61lude

can anyone give me a quick explanation of how a boost controller can prevent creep?

c61lude

no-one?

D@nnY

if you have a 10 psi spring in your wastegate and with the wastegate fully opened it creeps the boost controller will do nothing....

if you have an electric boost controller and a 10 psi wastegate spring and you set the boost controller to 17 psi and it creeps to 20

you can sometimes change the duty cycle of the solenoid to make the creep stop....it stops it by cycling the boost solenoid slower


You have to understand how the ports on the wastegate work.....its a very simple concept

theres a top port and a bottom port on the gate with a rubber diaphragm in the middle....when theres boost pressure on the bottom side the boost lifts up on the rubber and compresses the spring allowing the gate to open

when you use a electronic boost controller you bleeding boost back on top of the rubber to use boost pressure to keep the gate closed and raise the boost..

this is why you can only go more boost then the spring not less

c61lude

^^

I thought that it was the vacuum line that caused the wastegate to open and close. the ebc manipulates how much vacuum or positive pressure the wastegate will see and therefore allows for more boost

D@nnY

its a boost only line...wastegates dont need vacuum and when the motors under boost there is none

the boost controller jsut controls how much boos tto bleed onto the top port to keep the gate shut

simike

So how would a boost controller prevent creep? I thought creep was caused by a wastegate that can't get rid of the extra exhaust fast enough. The exhaust that should be flowing out the gate (when the desired boost level is reached) can't due to any number of reasons spools the turbo more and more causing the boost to creep higher and higher. At that point there should be no way of controlling creep w/a boost controller. It's a flow restriction? Someone please explain.

D@nnY

the way you stop creep is only if the boost control settings are casuing the creep...you can back the duty cycle down to allow the wastegate to fully open....like i said

if the gate has a 10 psi spring and it cant hold 10 psi with the gate fully open...a boost controller will do nothing

simike

Thats what I thought.........

c61lude

hmm. thanks guys. I guess I'll just end up upgrading my 38 to a 44

simike

Ever consider running dual gates? Just buy another 38mm. Thats what I am doing this winter.

c61lude

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by simike &raquo;</TD></TR><TR><TD CLASS="quote">Ever consider running dual gates? Just buy another 38mm. Thats what I am doing this winter. </TD></TR></TABLE>

yeah but then I have to cut into my manifold, weld another pipe and get more flanges. Ultimately it ends up costing more. Because I can sell my 38mm for like 125$

D@nnY

the 44mm tial v bands are good..they run about 350....

I have a 38mm turbosmart and a gt35R .82 ar t3 turbo and it creeps a little....with a 9 psi spring at 7500rpm it goes to about 14 psi