IW STi Forum banner
1 - 9 of 23 Posts

· Registered
Joined
·
2,262 Posts
Discussion Starter · #1 ·
So I was just browsing around Blouch's website, looking at 20G's for s***s and giggles, and it made me start thinking about the different calibrations that they offer for their TD05H-20G. Apparently they offer them pre-calibrated between 9psi to 19psi increments and so I was wondering what are you guys out there with 20G's running the actuator calibrated at and why? I know that the actuator controls the wastegate from the pressure taken from the intake manifold, but why would you choose say 9psi vs 19psi? Were some of you looking to lessen the amount of exhaust gases entering into the turbo because your exhausts are too free-flowing and by having the actuator calibrated at a really low psi that would all the wastegate open early? If that were the case, why wouldn't you just have a more restrictive exhaust that wouldn't allow as much exhaust gas to enter the turbine thereby allowing the actuator to be calibrated at a higher boost level? What are the pluses and minuses of having the actuator calibrated at a high boost pressure vs a lower boost pressure?
 

· Registered
Joined
·
2,262 Posts
Discussion Starter · #5 ·
calibrated higher it should boost a little quicker because its bleeding less.
I understand that, but then will it overboost because the wastegate isn't bypassing enough exhaust gases? I mean, what would make you choose it to be calibrated at 12 psi vs 18 psi?

At this point in time I am just starting to think that it's all dependent the volume that your specific exhaust is pushing out. So if your exhaust was very free-flowing it would be better to have an actuator calibrated at higher psi in order to maintain good control and vice versa.

Still curious as to what all of the 20G owners are calibrated at...
 

· Registered
Joined
·
2,262 Posts
Discussion Starter · #8 ·
Is the exhaust housing/waste gate is designed right it show not be more likely to creep.

re: 12 vs 18psi.

Supposed you have a meth setup with failsafe that is designed to run waste gate boost if a problem is found. running 18psi, may not be conservative enough in that case.
Yes, you're right about the design thing, but if enough exhaust isn't being bypassed, like in a scenario where the actuator is calibrated too high, then what goes in the turbine must also come out. Then the turbo will spin too quickly resulting in an increase in boost pressure. That will heat the air too much or even possibly damage the turbocharger.

I'm not talking about in regards to a meth setup. What are you saying?

I am just simply looking to find out why someone would choose one actuator calibration as opposed to another. Let's say that there are a bunch STi's all with 20G's and all of the same supporting modifications. Why would one choose one calibration as opposed to another?
 

· Registered
Joined
·
2,262 Posts
Discussion Starter · #12 ·
I have an external and I have a .8 bar spring I believe on a blouch 2.5r. It opens so fast its annoying (being external dump) I just bought a 1 bar spring and I don't plan on going any higher should be about 15psi spring pressure.
I think depending on your tune you could go as high as 18 but if your ecu ever encounters a problem and you go to waste gate pressure you'd be at 18lbs min. which may or may not be to much dependent on your tune.. See if you did have meth I'm sure you would want a lower rate or spring pressure since I'm sure meth starts to make a difference at that level of boost.
I don't know how to correctly answer your question... But I would choose a spring also based on what amount of boost you'd want your motor to see if there was a problem encountered.. Right?
and I'm surprised Blouch has yet to get back to you, they are really service orientated so I’m sure they will or just give them a call!
Did you buy your car previously modified and that's why you are unsure of what turbo you are using? Why is it annoying that the wategate opens so quickly? Were you not hitting your target boost pressure because your wastegate was opening prematurely?

I'm not talking about replacing the spring, I am talking about the calibrated boost pressure of an internal gate. Although, with both you are affectively changing when the wastegate opens.

I will probably just call Blouch or whomever when the time comes to upgrade the turbo.
 

· Registered
Joined
·
2,262 Posts
Discussion Starter · #14 ·
Yes, I understand in full the two different types of wastegates. I misread your first post and thought that you didn't know what kind of turbo that you had, sorry about that. The EWG is always going to be loud man, that's just the nature of the beast.

The internal gate is basically a poppet valve that opens and closes based on the pressure that it senses from the intake manifold. The wastegate actuator, which controls the opening and closing of the poppet valve, can be pre-calibrated to open at a certain pressure.

I can not believe that we still haven't heard anything from one 20G owner out there...
 
1 - 9 of 23 Posts
Top