Actuator adjustment and boost taper?
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Joined: Jul 2004
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From: Northern Virginia
Actuator adjustment and boost taper?
I was just wondering how to go about making sure that the actuator on my White Rabbit is properly adjusted. I've wondered if actuator preload could be responsible for some of the inconsistent results that people are seeing with the WR. It's just a guess, but if there isn't sufficient preload could that be causing excessive boost taper? Does FP set that up for you on their turbos generally? I have not run high enough boost levels on mine yet to see any significant taper, but I'm interested to understand better how to make sure that this adjustment is right.
Thanks
Thanks
Best possible adjustment point would be as tight as possible without moving the actuator rod at the diaphram. From there you are just tightening it past it's expected operation. Now that has and can be done but it is possible to break the arm the actuator goes on.
We usually adjust the arm so it is a 1/4 of a pin hole tighter than neutral. I hope that makes sense. What I am saying is if you put the actuator rod so it will slide right on the pin, tighten it so it is a 1/4 of a hole tighter. You will then have to slightly pull it to get it on. This puts a little pre-load on the actuator. If this causes excessive spiking then you may have to just run it neutral. Most cars like it just a little tight.
For extra high boost we have a HD actuator that has a 26 psi spring in it.
David Buschur
www.buschurracing.com
For extra high boost we have a HD actuator that has a 26 psi spring in it.
David Buschur
www.buschurracing.com
Thats correct.. The adjustment should be around where it puts enough tension on the flapper so it doesnt have any "Play"
Adjust the rod until it lines up with the hole and fits over, then turn it out 2 or 3 turns so it has to be "Coaxed" on slightly, that should give you just enough preload without being too tight.. I know how hard it is to adjust with that damn heat-shield in place, but if you plan on using an adjustable wastegate actuator, or making adjustments after everything is back together, you might want to trim it so you can access the adjustment and the cannister easier. (FWIW, if you have your hot side and O2 housing thermal coated, you can throw away the heat shield)
Adjust the rod until it lines up with the hole and fits over, then turn it out 2 or 3 turns so it has to be "Coaxed" on slightly, that should give you just enough preload without being too tight.. I know how hard it is to adjust with that damn heat-shield in place, but if you plan on using an adjustable wastegate actuator, or making adjustments after everything is back together, you might want to trim it so you can access the adjustment and the cannister easier. (FWIW, if you have your hot side and O2 housing thermal coated, you can throw away the heat shield)
