How to get rid of boost creep on 14b/16g MHI turbos.

[kidtsi]

Many people had been discussing how to get rid of boost creep, and/or how to run stock boost on a 14b/16g since they don't have the supporting mods or they just cant afford them.
This was done for my friend by me, he didn't have the money for supporting mods at that moment, this write up is for those people that want to run stock boost (as low as 11psi) on Mhi internally gated turbos.

This is similar to the Holset wastegate mod to hold more boost but the difference is this is for achieving low boost on MHI internally gated turbos without going with an external, this is the best solution i have seen so far.

Side by side comparison.

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And this is the final product, i used the bracket and the rod of the 14b/16g actuator (I used an eBay 16g actuator because i just needed the bracket and adjustable rod).

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This was the difference, notice how the MHI actuator is too restrictive when its fully opened.

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Now notice the modded actuator travel.

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This is how it looks bolted to the turbo.

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My friend is running solid 12psi on his car since march without any supporting mod more than a fuel pump rewire on his 2g, that's the most boost i recommend for a stock fuel system after watching what was happening on my Dsmlink when i put it at 15psi.

If you have any questions/opinions feel free to post in here or pm me.

Kevin.

 

[williillii]

I have one, what wastegate did you use?

 

[kidtsi]

I have one, what wastegate did you use?

MHI and a t25 Garret.

 

[1990AWD]

What did you actually do here? Make the rod longer?

 

[JusMX141]

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Nice mod, but had you ported the wastegate hole on that knockoff turbine housing a little, you would not have needed to build such an actuator.

Before:

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After:

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It should also be noted that the spring tension of the T25 actuator is a little weaker than that of a MHI 14B/16G actuator....it will open at around the same PSi, but it doesn't have as much tension to pull the flapper closed from the added distance that it is allowed to open. Of course this is only an issue when you're attempting to run higher boost levels.

We tried using a T25 actuator on my buddy's Frank Level 5 20G years ago, before my first Holset actuator mod was attempted, and the most boost we could run was 17-18psi even with the boost source completely disconnected from the actuator head and plugged. This was with a 34mm wastegate flapper.

 

[kidtsi]

What did you actually do here? Make the rod longer?

The actuator of the t25 opens like twice what an 14b/16 actuator can, i welded the 14b/16g braket to the actuator of the t25 and also the rod since the rod need to be longer.

 

[kidtsi]

It should also be noted that the spring tension of the T25 actuator is a little weaker than that of a MHI 14B/16G actuator. We tried using a T25 actuator on my buddy's Frank Level 5 20G and the most boost we could run was 17-18psi, even with the boost source completely disconnected from the actuator head and plugged. This was with a 34mm wastegate flapper.

The knockoff turbo its for display only, my friend's turbo is already on the car, also i claimed that this is to run low psi on a 16g if you don't have supporting mods, u can easily swap the actuator to an original MHI if your trying to boost more than 18 psi without removing the turbo.

EDIT: His turbo is an MHI big 16g with a 34mm flapper and was creeping to 19psi with all the porting and 34mm flapper before this mod.

 

[JusMX141]

His turbo is an MHI big 16g with a 34mm flapper and was creeping to 19psi with all the porting and 34mm flapper before this mod.

Is he running an open downpipe or something?

I ran the same exact turbo and wastegate flapper setup (MHI Big 16G, FP-ported turbine housing with 34mm flapper) on my TSi FWD a bunch of years ago prior to any fuel system mods and it held 12-15psi rock-steady to redline with the stock actuator and a catless 3" turbo-back Thermal R&D exhaust.

 

[kidtsi]

Is he running an open downpipe or something?

I ran the same exact turbo and wastegate flapper setup (MHI Big 16G, FP-ported turbine housing with 34mm flapper) on my TSi FWD a bunch of years ago prior to any fuel system mods and it held 12-15psi rock-steady to redline with the stock actuator and a catless 3" turbo-back Thermal R&D exhaust.

His running a Apexi 3 inch cat less Downpipe and a 3 inch exhaust, for what i have seen boost creep is different in every car. I did this to help people that don't want to remove the turbo and run with it with stock fuel system, i mean i spend $5 on making this. his running 12 psi without any boost creep, sometimes we turn it up to 14 and no boost drop what so ever.

EDIT: keep in mind the different altitude, i live in Texas.

 

[dsmdeliveryboy]

I'm running a 3" catless tbe, a 14b with a MHI 7cm housing and the flapper hole is ported. I'm still getting boost creep up to 20+psi and am only trying to run 15psi. I have tried 2 different wastegate actuators and different shimming. Without shimming them, both of the wastegates cause the flapper to blow slightly open, I get horrible boost lag and still creeps. With them shimmed, the turbo virtually has no lag and creeps.

PS: I have a new Hallman Pro MBC, no boost or vacuum leaks, and everything is hooked up correctly.

 

[kidtsi]

I'm running a 3" catless tbe, a 14b with a MHI 7cm housing and the flapper hole is ported. I'm still getting boost creep up to 20+psi and am only trying to run 15psi. I have tried 2 different wastegate actuators and different shimming. Without shimming them, both of the wastegates cause the flapper to blow slightly open, I get horrible boost lag and still creeps. With them shimmed, the turbo virtually has no lag and creeps.

PS: I have a new Hallman Pro MBC, no boost or vacuum leaks, and everything is hooked up correctly.

What actuators had you tried?

 

[dsmdeliveryboy]

A 16g and 20g actuator..

 

[kidtsi]

A 16g and 20g actuator..

If you are trying to boost less than 18 psi, why don't u try this? From what i know the 14b/16g actuator have the same travel.

 

[dsmdeliveryboy]

If you are trying to boost less than 18 psi, why don't u try this? From what i know the 14b/16g actuator have the same travel.

The 14b, 16g, 18g, and 20g actuators are all the same except for the FP18g actuator is like a 14.7psi actuator or something.. I'm probably just gonna go external, buy a Ebay o2 housing and wastegate or something of that sort.

 

[kidtsi]

The 14b, 16g, 18g, and 20g actuators are all the same except for the FP18g actuator is like a 14.7psi actuator or something.. I'm probably just gonna go external, buy a Ebay o2 housing and wastegate or something of that sort.

If u have an extra 14b/16g actuator and a t25, why don't u try this?
You are going to spend 200 bucks if you go external with eBay parts.

 

[juanjose]

i have a t25 and a 13g(i think) it came with the car i think its from a jdm rvr engine
do you think i can use this actuators to make the one u have. thank you

 

[dsmdeliveryboy]

If u have an extra 14b/16g actuator and a t25, why don't u try this?
You are going to spend 200 bucks if you go external with eBay parts.

PM me with a price for you to build and ship, not really looking to spend a whole lot but if you wanna hook it up and it works I'll def recommend it to people.

 

[kidtsi]

i have a t25 and a 13g(i think) it came with the car i think its from a jdm rvr engine
do you think i can use this actuators to make the one u have. thank you

if its a 13g then yes.

 

[hurricanecris24]

PM me with a price for you to build and ship, not really looking to spend a whole lot but if you wanna hook it up and it works I'll def recommend it to people.

I need this mod done to my car also. I have a full 3 inch turboback and I have it connected to my wastegate and it creeps all the way to 20± but when I put my stock cat on it doesn't creep at all. I have an evo 3 16g and manifold with ported o2

 

[kidtsi]

Update: Throughout the winter the turbo never creep-ed.

 

[jrohner]

My question is why would you ever want to run only 12-15psi?

 

[kidtsi]

I'm not running near that, it is my friend's car without supporting mods.

 

[spydreclips6]

So I'm guessing you just cut the ebay 16g rod, and welded it onto the t25 rod?

 

[toyotagt1]

im running 15psi steadily all the way to redline no problem with a 100% stock 14b with a hallman boost controller the only thing i have done really right now is a walbro 255, fuel pump rewire, a full 3in turbo back megan racing exhaust and my a/f ratio is rich but is fine i dont no why so many people have this problem me and my friends have never my friend is running 22psi no problem to redline with his b16g

 

[forcefed86]

Tried to help out a local friend with similar issues. His "tooner" told him not to go over 20lbs. He had a bone stock E316g and 3" DP and full 3" exhaust. Even with my beefed up garret adjustable actuator opening the flapper all the way he would continue to spike over 20psi. The goal was 20psi flat to redline.

I think the exhaust size was the culprit. If he left the boost down low it would not spike. But of course he wanted to be at the 20lb power level. I think once these 16g's get to that point they just like to over spool without porting.

I was able to run 24psi with no spiking on my e316g. With the same actuator, ported manifold, flapper hole, housing with 2.5" dp and exhaust.