falcongsr

i want to set this 18g internal wastegate to the absolute MINIMUM possible. (about 5-6psi maybe?)

i think i need to lengthen the actuator arm so that the wastegate flapper opens as soon as possible?

can someone confirm this? thanks.

turbod16y7vtec

not sure about this but i am interested to.. if someone could let us know i also need to turn my boost down...

falcongsr

Dr. Evil: somebody throw me a fricken bone here.

falcongsr

falconGSR: do you know how to set the boost level on an internal wastegate turbo?
tma334: well it depends on the springs pressure
tma334: most springs are 5-10 psi
falconGSR: yeah
tma334: if you want to find out what your spring is set for, you'll have to hook a vac line off the intake plennum and see what your max boost is
tma334: and if you want more, add in a bleeder, or a hobbs switch, if you want less.. well that's the hard part =]
falconGSR: but the actuator arm can open the wastegate earlier or later
falconGSR: for lower and higher boost
falconGSR: its different than external
tma334: u have internal
tma334: right?
falconGSR: yes
tma334: well, the actuator will fully extend at a certain psi
falconGSR: and i am going to use a gm boost solenoid with the ems and control boost like that. need to minimize boost for early testing this weekend
tma334: the minimum boost you can run is what the spring's internal seat pressure is
tma334: to get it lower, you have to either swap the spring out, or lengthen the wastegate arm more (cheap way)
tma334: on my car, i just lengthened the actuator while i test things
falconGSR: well the arm is threaded with a nut on it so i'll lengthen the arm
tma334: i run about 2 lbs of boost
tma334: cool, then that makes it easy
falconGSR: yup
tma334: but the problem with doing it that way, of course, is boost comes online a bit later due to the bled pressure
tma334: my car is pretty quick, even with 2 lbs
falconGSR: thats where the boost control solenoid comes in
falconGSR: since it will keep the wastegate closed
tma334: it will help, but to get the drop in boost you want, your wastegate *fully closed* will be partially open
tma334: because if you extend that arm, the WG flapper sits slightly unseated
tma334: and then opens farther "earlier" giving less boost
falconGSR: i wont extend it that much then
tma334: just all depends on how much boost you wish to run
falconGSR: well...as little as possible at the moment
tma334: but of course, once you get everything up to par, the BCS will help quite a bit
tma334: i use a grainger valve, has a spring and a steel ball that seats, and you adjust the spring tension for boost. works great
falconGSR: i got 2 of those at home
tma334: yea, i use them exclusively.... cost about 9 bucks to make
falconGSR: yup
tma334: it's time to turn the boost up on my car
tma334: and probably raise the revv limiter
tma334: 8,000 rpm is just not enough
falconGSR: hah
falconGSR: i can tell when the flapper is unseated from the turbo housing. i'll move it so its still closed.
tma334: there ya go
tma334: just loosen the seat pressure
falconGSR: cool thanks

ahh i get it now. that guy has a geo storm with a built isuzu dohc motor with t3/t04e turbo tuned with AEM EMS. dont ask me why he's running a Geo Storm...talk about a sleeper!

DeepSi

so were you able to lower the psi's? or have you have not tried it yet.

-deepsi

FredoSP

I think 5 psi sucks as is, why go lower Joe?