Boost Characteristics of A Large Turbo
Anything larger than a 1 bar spring really isn't really needed unless you are running really high boost, so i would switch it out (not to expensive). My EBC controls the the WG to open at a given psi, so i never had a problem with creep or spike with my tial. I'm not sure that you should upgrade to a EBC until you have tried everything even though it does seem your MBC is acting funny.
I agree with nez136's. More than one bar is two big of a spring for your set up.
EXAMPLE on 18-19 psi spring( tial 44)
big turbo, pump gas, EBC off...wastegate controlling boost
big turbo , race gas, EBC set at 30-38 psi
This was on my supra, if u can live with driving around on 18 psi on pump, and run race gas on 30 psi. then ur ok with that spring.
A couple of buddys of mine were having problem with there srt-4s, they bought a adjustable actuator, and MBC and boost was all over the place. They were trying to set wastegate to 18ish psi and then turn it up to 20-22 psi. They finally got it when they turned the wastegate down and boost up with MBC.
Damn kids
One more thing what wastegate does he have? 38 or 44? the post jumped around a little bit on that subject.
EXAMPLE on 18-19 psi spring( tial 44)
big turbo, pump gas, EBC off...wastegate controlling boost
big turbo , race gas, EBC set at 30-38 psi
This was on my supra, if u can live with driving around on 18 psi on pump, and run race gas on 30 psi. then ur ok with that spring.
A couple of buddys of mine were having problem with there srt-4s, they bought a adjustable actuator, and MBC and boost was all over the place. They were trying to set wastegate to 18ish psi and then turn it up to 20-22 psi. They finally got it when they turned the wastegate down and boost up with MBC.
Damn kids
One more thing what wastegate does he have? 38 or 44? the post jumped around a little bit on that subject.
1bar=~14psi (E/MBC off), you should be fine with 23 psi. You don't often here of issues like this...
I guess, but i always like the fact that if conditions are really bad or something fails and/or goes wrong i can run the car on kind of a safe mode (1 bar). Example; on my '03 i accidently put a half tank of 89 octane in my car (dont ask), with my highway driving (more load) it is very easy to hit a boost spike and maybe blow the motor at my normal 22psi. Thank god i could turn it down to WG pressue so i didn't have to worry about it
Well now, we just have to be a little more alert next time.
But seriously, with pump fuel only and the right WG spring combination, no other means of boost control or tuning is needed.
Neat how that works, huh?
yes but adjustment sucks. u would have to unbolt the top of the wastegate to change/add springs everytime u wanted to add boost. not only that there is no fine adjustment.






