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Discussion Starter · #1 ·
Hello,
I'm curious about the purpose of this hose clamp (purchased car w/ this). Is this holding my wastegate closed? The car is BPU w/ a JDM GTE swap. I've done some searching and have read a bit about the spring mod. This seems to be related. Pic is looking up from front right corner.
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Should I be concerned about this or do something different?

How would this affect installing a boost controller? I do not have a BCC and hit boost cut w/ the cool temps if I push it. I have future plans for upgraded twins and fuel upgrades and ponder my options until then. I don't often hit boost cut and am thinking about getting dyno baseline numbers before I make other mods. I imagine solid dyno runs can be made w/out a BCC. Please advise if wrong.

Thank you,
Erin
 

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Boost Junkie
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It looks like someone installed a clamp instead of doing the spring mod to the wastegate actuator. You def need a BCC. I'd also perform a vacuum/boost leak test to see if you have an boost leaks.

Steve
 

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Discussion Starter · #4 ·
@1A1 and @supradriver247, do I understand the point of this correctly? The spring mod (or clamp in this case) holds the wastegate closed so boost pressure cannot be bled off. This means my turbos are at max boost for any given RPM (i.e. exhaust flow rate) and boost more quickly. With the clamp, there is no variability (not sure if there is much w/ spring). Is this accurate?

Why would someone use this method over the spring? Are there downsides to this setup or any reason to swap to a spring?

Let's pretend I buy/install a BCC in the coming days. I would then want to install a boost controller to keep my max boost at or under 18psi on stock JDM twins w/ 93 octane, correct? Will this clamp have any adverse effects on a boost controller? My OEM piping has been shaved, so I need to do some learnin' on where to install a solenoid. I'm in TTC.
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I plan to install upgraded twins next year-ish (still deciding between JDM or USDM - leaning JDM) and upgrade my fuel system. I already have a performance fuel pump and big fuel lines (from the car's previous life w/ different drivetrain and owner) and am starting to learn about piggyback ECU's to add larger injectors (I have USDM 550's and resistor on the shelf; thinking it might be easier to simply add a piggyback and continue to use high impedance injectors; maybe I'm being lazy; I digress). That is all to say, it sounds like a boost controller should be part of my plan, ESPECIALLY if I install a BCC. My eventual goal is a highly reliable 500whp. If I understand correctly, right now my turbos will always be at max boost, meaning the only thing keep me from any damage is the stock boost cut. I can reliably hit the limit w/ the cool weather.

I can easily test for vacuum leaks (carb cleaner or Mityvac). Any tips on checking for boost leaks? Build a pressure regulator and pressurize the intake system?

Thank you for your time,
Erin
 

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Discussion Starter · #5 ·
Also, I've done more reading on the spring mod. There's some good info out there. I'm not looking to change my current setup if there's no reason to. Car runs very well and feels strong. I installed boost and a/f gages last week although have not driven the car much since (and am now out of town). Plus, I had to work w/ AEM to get a new boost gage b/c mine was reading 2.4psi w/out engine running. New one is in the mail.
 

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The clamp just helps hold the waste gates so the engine will make more boost. Yes, this will cause your car to run more boost all of the time. When it gets colder you’ll definitely hit boost cut without the BCC. I don’t know much about JDM stuff. I’m not sure how the ECU will respond to more boost. US spec have a MAF so you don’t have to worry about it.

For the boost leak test, you need a boost leak checker, which you can purchase at several vendors. You’ll basically install it on the intake to the turbos and use an air compressor to pressurize the entire system and listen for leaks. You may need to block off the valve covers and the crossover between the valve covers when you do this.

I wouldn’t run more than 17-18 psi on 93. If you use a high quality fuel you’ll have full timing and make the most power.

Steve
 

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It appers that you have export spec turbos on your set up. I have had my JDM turbos off and I dont recal that 1" corrogated pipe that is in your picture. I believe that pipe belongs to the EGR system, the JDM cars didnt have an EGR system.
 
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