Will 16g turbine housing work on 14b?

[tsi1991awd]

As the subject says, will the 16g turbine housing work with a 14b? I would have my 14b turbine housing ported, but I can't afford down time and I don't have the tools to do it. I can get a ported 16g housing....I have a feeling it won't work though.

 

[tsi1991awd]

OK, so then my question is, can I run 15psi with just a MBC and port the 14b housing and keep everything else stock, or do I still need to do the fuel mods? And can the SMIC hold 15psi?

I'm not trying to cheap out, I'm just not trying to spend a lot and max the car out right at this point in time.

 

[dsm-onster]

Only a logger can tell. I had two of the same DSMs at one time: one liked 16psi and didn't fuel cut but knocked. The other fuel cut at 14psi, but once I tackled the fuel cut, didn't knock until 18psi. You arn't going to be given a straight answer, no matter, how many reply, because we don't know your car. You don't either until you log what is happening.

If you can't afford a logger, then you can'rt afford the damage that could result from not logging. . . A logger isn't expensive though. Search for a 1g logger. These forums are FULL to the rim with 1g logger info. You have a 1g. You can easily log injector duty cycle (how close to the limit your fuel system is) and you can actually see a knock count to tell you if your tune is beating on your motor.

 

[tsi1991awd]

I just talked to the shop that has the 16g turbo housing. They said it is already ported at the wastegate entrance. I asked if it had a wastegate flapper already installed and what size, and they said 1.25

What's 1.25?

 

[dsm-onster]

Inches? 1.25inchs X 25.4mm/inch = 32mm. Is the WG hole ported to 32mm with a 34mmflapper installed or is the flapper 32mm? The stock flapper is a hair over 30mm in diameter (1 3/16"). Why didn't you ask them "1.25 what?"

 

[tsi1991awd]

Yea 1.25"...so 32mm. That's the flapper size. Does it really need to be 34mm for what I want to do, or even if later on I do the fuel upgrades and FMIC, etc and run 20psi?

 

[No_Skillz]

...or even if later on I do the fuel upgrades and FMIC, etc and run 20psi?

Do this instead. A bigger flapper will help with boost creep by allowing more gas escape, but when you eventually decide to up the boost (as everyone eventually does), you'll find that it blows open easier.

 

[dsm-onster]

Yea, the smaller the flapper the better off you are for higher boost. The wastegate actuator spring for these 14b-16g turbos are weak. A largerflaper will blow open once you start developing the backpressure it takes to hold 20+ psi to redline. This should be enough. And if you can't hold more than 22psi, then first check for a boost leak, then try shimming your wastegate actuator and resetting your manual boost controller for the tighter spring load.

 

[tsi1991awd]

Well the first question is what if I only run 20psi max. Second question would be where do I get a 34mm flapper and is it easy to install?

 

[No_Skillz]

Well the first question is what if I only run 20psi max.
Second question would be where do I get a 34mm flapper and is it easy to install?

How much boost you hold all depends on the amount of force the spring in the wastegate can provide. All wastegates are a litte bit different so you would just have to test with an air compressor hooked up via a hose. I would guesstimate that if your flapper can hold 23-25psi, a 34mm would hold under 20psi.

A 34mm wastegate can be had here:Forced Performance Turbochargers: FP 34mm Wastegate Flapper A bit on the expensive side but it's all I got with a quick search.

Just a quick calc for ideal conditions (for shits and giggles):

ForceOn32mm 20PSI
-------------------=----------
ForceOn34mm TestPSI

Since we're just dealing with proportions and the force on the flapper is directly proportional to area of flapper, we get:

Area32mm 20PSI
-------------=-----------
Area34mm TestPSI

(32/2)^2(3.1415) = 804.2
(34/2)^2(3.1415) = 907.9

804.2/907.9 = 20/TestPSI
TestPSI = 22.6psi

In theory if you pressurized your 32mm wastegate to 22.6psi, it should hold 20psi with a 34mm flapper.

However, keep in mind that this calculation is not 100% accurate since it's assuming that your wastegate hole is the same size as the flapper (which it's not: it's smaller). It's just so you can get an idea (and because I'm bored at work). Keep in mind that since the size of the wastegate hole is smaller, the same change in size is a greater ratio of change, so you will want to use a higher TestPSI in real conditions.

 

[tsi1991awd]

How much boost you hold all depends on the amount of force the spring in the wastegate can provide. All wastegates are a litte bit different so you would just have to test with an air compressor hooked up via a hose. I would guesstimate that if your flapper can hold 23-25psi, a 34mm would hold under 20psi.

A 34mm wastegate can be had here:Forced Performance Turbochargers: FP 34mm Wastegate Flapper A bit on the expensive side but it's all I got with a quick search.

Just a quick calc for ideal conditions (for shits and giggles):

ForceOn32mm 20PSI
----------------- = ----------
ForceOn34mm TestPSI

Since we're just dealing with proportions and the force on the flapper is directly proportional to area of flapper, we get:

Area32mm 20PSI
-------------- = -----------
Area34mm TestPSI

(32/2)^2(3.1415) = 804.2
(34/2)^2(3.1415) = 907.9

804.2/907.9 = 20/TestPSI
TestPSI = 22.6psi

In theory if you pressurized your 32mm wastegate to 22.6psi, it should hold 20psi with a 34mm flapper.

However, keep in mind that this calculation is not 100% accurate since it's assuming that your wastegate hole is the same size as the flapper (which it's not: it's smaller). It's just so you can get an idea (and because I'm bored at work). Keep in mind that since the size of the wastegate hole is smaller, the same change in size is a greater ratio of change, so you will want to use a higher TestPSI in real conditions.

So if the 34mm flapper holds less psi, that's good? That doesn't really make sense to me.

 

[No_Skillz]

So if the 34mm flapper holds less psi, that's good? That doesn't really make sense to me.

No, the calc goes to show that if you wanted your 34mm flapper to hold 20psi, you will first need to test that the same wastegate with a 32mm flapper will have to hold more.

 

[tsi16g]

ok i have a question thats kinda on the subject at hand.... i got a 91 tsi and it came with a 14b on it but when i took it off the car to upgrade to a 16g the housing was from a big 16g... i looked up the numbers and it is a 16g housing, i wanted to know if i can just swap the turbine wheels to a big 16g or should i just get a big 16g????

 

[manny correa]

^ yes you can! all turbine wheels are the same between 14b/16g. there all tdo5h wheels. the sizes vary in the compressor wheels.

 

[tsi16g]

o ok so i can just get a 16g turbine wheel and be good to go

 

[Rich_Howell]

o ok so i can just get a 16g turbine wheel and be good to go

uhhh...no. You already have a "16G" turbine wheel.

Whether you have a 14b or small 16G or Big16G or Evo3 16G or (most) 18g or the FP 68HTA...you have the SAME TURBINE WHEEL! It's called a TD05H. THE ONLY DIFFERENCE between these turbos are the COMPRESSOR WHEELS...named...14b...16g...big16G...e316G...18G...HTA68

IF you have a turbine housing for any of these, they will work on any other of these. Again...this is possible because they all have the same turbine wheel. If you have a 7cm^2 turbine housing from a (any) 16G on your 14b...and you want to upgrade to a 16G, all you need is the 16G Compressor housing and wheel and CHRA with turbine wheel...and it will fit into your existing housing. You could do the same with a 6cm^2 turbine housing from a 14b and swap-in any of the aforementioned comp/wheel/CHRA/turbines (s16G, b16G, e316G, 18G, 68HTA) but you will never come close to finding the potential of really any of those compressors with that housing. It's hard to find the limit even with the 7cm^2 housing (unless with a 14b or s16g). Most 18g's I've seen have an 8cm^2 turbine housing...which may help with any of those compressors (overkill for s16g and super overkill for 14b though).

Make sense?

 

[dsm-onster]

You have to swap the backplate when swapping a 16g wheel onto the 14b chra as well. The 16g/18g/20g has "superback" tech in it.

The 7cm^2 turbine housing and tdo5h turbine wheel I feel is a little too small even for the evo3 16g compressor. About PERFECT for a small 16g compressor, the perfect balance of flow and spool to get the best out of the whole turbo. Guys have been hard pressed to see 44lb/min out of a 20g compressor mated to the td05h hotside with a 7cm^2 housing. The fp68hta flows 47lb/min; the 20g flows 48lb/min. You have to do LOTS o' mods to get the exhaust efficient and "ready" to go through that restrictive hotside to get the most out of the compressor. Expect an fp exhaust manifold upgrade, more aggressive exhaust cam, and perhaps even a SMIM to see that much flow out of it.