Suspend your desire to fix a problem, ignore WHY I might want to know this:

 

Does anybody have a good feel (or hard doc/experience) with how long the wastegate clapper can stay off of its seat before something burns or otherwise gets damaged?

 

As in, if you ran a turbo at its gated-boost limit, how long before its wastegate was damaged?

 

How long before damage if wastegate was open at low-power settings (an otherwise non-positive manifold-pressure situation)?

 

Thanks in advance!

IF YOU RUN IT OPEN, BYPASS MODE, you will have low to no boost

 

IF YOU RUN IT CLOSED, NORMAL MODE, you run the risk of over-boost

it shouldn't bother it..

after all it never see's the same temps a a exhaust valve see's

but like lots of things i could be way far wrong...go figure

IF YOU RUN IT OPEN, BYPASS MODE, you will have low to no boost

 

IF YOU RUN IT CLOSED, NORMAL MODE, you run the risk of over-boost

Please reread first line of my post.

 

I have no intention of running the turbo outside of its boost range. I have some turbo experience dating back to the '70s (back when I had to deal with flow maps to find which $1000 unit best suited my application), and am not likely to do anything truly stupid.

BUMP for the West Coast lunch crowd.

BUMP for the night crew...

so what your saying is my reply is not good enoughf or you huh...

you have to bump it and get more ???

shesh...

Theoretically, at lower power levels, the wategate flapper could be off of its seat indefinately without damage.

 

 

Also, I think, theoretically, if the engine was under heavy load, and the exhaust gas temp was very high, an unseated flapper could get red hot in a matter of seconds. depending on what it was made of would determine whether or not it was damaged.

Theoretically, at lower power levels, the wategate flapper could be off of its seat indefinately without damage.

 

 

Also, I think, theoretically, if the engine was under heavy load, and the exhaust gas temp was very high, an unseated flapper could get red hot in a matter of seconds. depending on what it was made of would determine whether or not it was damaged.

I understand both of your points. The real answer to my question lies, I think, in the original design and application specs for the turbo. It had to be able to withstand SOME period of time with wastegate clapper off of its seat, and from what I have heard (I don't have a boost gauge or anything else on my car that would tell me), the EA82T can run enough boost to keep the wastegate open. SOoo, sounds like Subaru either knew it was OK or just ignored it.

ok

teh way that i know that these things work

is when you start to get near the max boost psi the springs in the wastegates have

is they start to "crack" open

so you boost slows down a bit before it reaches max psi

a mbc over comes that in ways

but you still suffer from that before max psi wastegate cracking psi problem

either way

the system

is stil partially open just before the max psi is achieved

 

now going to electronic boost controll

well thats diffrent

as the electronics

keep the waste gate closed totally until the set psi is reached

then open it all at once

and after wards usually pulse the duty solenoid on and off to keep the wastegate can at the max boost you want

 

now

since with electronic boost control keeping thewastegate closed up until the set psi

the result is a car

that has a faster boost responce <no sorta open wastegate>

its more precise once it hits max psi

and usually alot more responsive since the wastegate has no affet

until the setpoint is reached

on the other side

the smaller waste gate cans have weak springs alot of the times

so just the shear exhaust pressure can force the wastegate off its seat

 

one of the reasons i wil be swapping my saab wastegate can onto the suby turbo

its a bigger can

bigger spring

but ahh there is a catch

its opening psi is 5lbs

but thats parts of the good side

since i runs a saab apc it measn

until the apc hits the boost i want it will deny the wastegate signal to the can

but on the otehr side

if the apc picks up any problems

it ca also drop the boost as far as 5psi

 

anyways

enough of my insane rambling

Oh, oddcomp, I guess I ignored you again, sorry... i was too busy washing my hair... or was it watching the grass grow... wasn't watching the paint dry, 'cuz its too wet to paint...

 

I now how you can help me: give me a turbo and I will see how long it takes to burn the wastegate! lol

ah dam

well see your s.o.l

i have one thats sorta useabkle as a emergency spare

and the other well..

unless you consider a half inch of in and out lay on the shaft god..

then well no spare turbo's for you

oh wait

 

i do have a saab 9k turbo i gott a rebuild one of these days

and i have the turbo off a buick grand national that was carbed that needs a reuild as welll

ah dam

well see your s.o.l

i have one thats sorta useabkle as a emergency spare

and the other well..

unless you consider a half inch of in and out lay on the shaft god..

then well no spare turbo's for you

oh wait

 

i do have a saab 9k turbo i gott a rebuild one of these days

and i have the turbo off a buick grand national that was carbed that needs a reuild as welll

Hey, I don't need it to produce any boost, just "sit there and take it".

Too much work to change one out, even more work to drive down and see your sorry face .

 

I can't believe that with all of these folk pushing the limit on their turbo's boost that they haven't an opinion on wastegate longevity. I guess they want it closed, not open!

Oddcomp, PM'ing you

welll.. hell nice and tight wastegates.. makes for faster boost and more fun

loose sloppy wastegates are no fun ..