wastegate spring limits?

[renxun]

actually this idea actually stuck my mind... how do we determine that a spring in a wastegate isnt holding the boost and leak during boost build up?

lets say i have a 0.8bar spring and a boost controller. although i have a boost control and can push way up to 25psi but how do i know if my wastegate spring had hit its limit? how do i know if there is any boost escaping during boost buildups? i had always wonder that i might having somesort of leak hence slow down my boost building up which is not a good thing...

since im using a trust 50mm.. there is a screw to tightened the spring preload.... if i were to tightened it a fair bit, would i be facing boost creeping?

 

[nan83]

just dump the wastegate pipe to atmosphere..... so you can hear it leak or not.

but you must know, wastegate must open faster than target boost.. such as will open at 0.65bar if target 0.8bar.... if it open at 0.8bar, if course it will spike or creep.

the funtion gain or respond at digital boost controller is to play with wastegate opening.... if set hi gain, w/g will open at 0.7-0.75bar.. so the car will be more respond. Too hi gain, it can cause spike & creep.

so far my 38mm tial ( 1bar spring ) can hold more than 2bar.. no prob... if it start leak, it not the spring prob, it just valve not seat properly or mech. damage abuse by heat..

 

[jinkl]

just like nan83 said

if its leaks, u can hear it :D

my opinion is get a good boost controller , what opens the valve is not ur exhaust pressure, but the boost source pressure , if you are using a electronic boost controller , for example Profec B , if you set for your boost to be at 2bar , u may set to crack open at 1.8bar , the GAIN setting is to determine how fast u take from 1.8bar to reach 2bar

if your wastegate is a 0.8bar spring , and u use a electronic boost controller , u set the boost to 2bar at boost controller, what the controller actually does is supply only 0.8bar to the wastegate but actually ur real boost is 2bar :P , got it bro , i know its abit confusing hehehehe, thts the best i could do

 

[nan83]

hehehe... if set 2 bar.. no need gain oso power..

digital boost cont. very nice if use with big bush bearing turbo... can feel the diff... ball bearing only fast a lil bit...

 

[renxun]

now my boost controller is a very "canggih" kampung style air regulator which pl use to set air pressure for pneumatic valve. it can set from 0 - 4 bar...

although i had open wastepipe but since the pipe is quite long i might not reli hear if it leaks.....if i tightened the preload wat will happen?

 

[pioneer411]

bro, if me not wrong, wastegate use 2 hose, one at top at spring part, one under diaphram which boost come then pressure the diaphram open, now the better way, i think u use both of the hose, which atas itu, use boost controller to adjust boost masuk to pressurise the top part, which when running high boost, the wastegate still tutup which tahan by the pressure, which belum sampai ur desire boost...

i not so good in explanation, if u stil not understand, i can send u the pics, then u can follow the manual and try, pls ask ur mechanic also
heheh