Which Wastegate?

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Tein

So much with a little D
I am confuse which wastegate i am supposed to purchase... I am going to purchase a GT35 Turbo and boosting something around 16lbs of boost... so I need what a 38mm or 44mm? 0.5 or 0.6 bar? :confused:

I need some help fast cause I would made the purchase tonight... Thanks
 
It depends on the manifold you have. The 38 uses a 2 bolt flange and the 44 uses a v-band flange. The 38 is a good wastegate but wont stand up to a heavy use of race gas. If you plan on using just pump gas and race gas a little, the 38 will be fine. The bar is just the pressure rating of the spring. With just 16 pounds, either will suffice. Its just when you get into heavy boost will it be a problem.
But still, its up to whatever manifold you have.
38mm
http://www.comotorsports.ca/osCommerce/catalog/images/Products/Wastegates/TIAL38-225225.jpg
44mm
http://siliconestop.com/images/2904_1.jpg
 
The "type" of gas you areusing will make no difference as to what wastegate you should choose. How much power are you trying to make out of your setup? If your manifold is already flanged then of coarse that will initiially dictate what wg to run, but adaptors can be made to convert a 38 to 44.
 
^How much power can you make before you should switch from a 38mm to 44mm?
 
What sized turbo and what motor also comes into factor there. The amount of exhaust gas needing to be dumped is basically what it boils down to.

There's alot of factors that make it to difficult to say that at "x" hp you need to go up to a 44. We've done setups that were well over 400hp on 38mm gates. Our H22 car last year made right over 700 on a 46mm Tial gate and 67mm turbo
 
Is there a performance decrease if you just went with a 44mm if your not taking full advantage of it? I would guess not.
 
just get a 38mm tial and call it a day, O by the way, if your going to be boosting 16psi you want a 8psi spring in your wastegate, Rule of thumb with wastegates is boost 16psi divided by 2 = 8 psi
 
Is there a performance decrease if you just went with a 44mm if your not taking full advantage of it? I would guess not.
No, I can't see where there would be an adverse effect. You are still using the same wg spring pressure so even on low boost amounts the wg would basically work the same regardless

O by the way, if your going to be boosting 16psi you want a 8psi spring in your wastegate, Rule of thumb with wastegates is boost 16psi divided by 2 = 8 psi
That's not really true. The "rule of thumb" is you can basically double the wastegate spring pressure safely. You could run an 8, 10, 12 psi spring and reach the 16psi just as easily, you'd actually be better off with the 10 or 12.
 
No, I can't see where there would be an adverse effect. You are still using the same wg spring pressure so even on low boost amounts the wg would basically work the same regardless.

Wouldnt goin with an oversized wastegate make it harder for the gate to control boost at low levels?
 
why dont u just go with a tial 44 gate and be done and a .07 spring cause i bar is 14.2 i think or somewhere are there just get a 44 gate so u wont kick urself in the ass if u build that motor and want to crank the boost up
 
The "type" of gas you areusing will make no difference as to what wastegate you should choose.
Im not trying to be a d!ck or anything I just know this from experience.
Weve had customers go through a couple before this option was available.
From Tials website TiAL Sport.com

""Valve Stem Options
The TiAL F38 is the only wastegate with the option to choose the valve stem's protective coating. To keep the overall cost of the unit down, the choice of coating was left to the customer.
Lead Oxide which is present only when burning leaded fuels is corrosive to the Black coating on the Street valve's stem. Extended use of leaded fuel will cause performance problems and unreliable valve actuation.
The Silver coating on the Race valve stem is resistant to the corrosive effects of Lead Oxide. Similarly works well with unleaded fuel. The Racing valve is available for an additional charge.""
 
Im not trying to be a d!ck or anything I just know this from experience.
Weve had customers go through a couple before this option was available.
From Tials website TiAL Sport.com

""Valve Stem Options The TiAL F38 is the only wastegate with the option to choose the valve stem's protective coating. To keep the overall cost of the unit down, the choice of coating was left to the customer.
Lead Oxide which is present only when burning leaded fuels is corrosive to the Black coating on the Street valve's stem. Extended use of leaded fuel will cause performance problems and unreliable valve actuation.
The Silver coating on the Race valve stem is resistant to the corrosive effects of Lead Oxide. Similarly works well with unleaded fuel. The Racing valve is available for an additional charge.""
I wasn't trying to be a dick either (if it came off that way, I apologize). I just wouldn't want someone to read and think "Well I'm going to run race gas some so I must need a 44" when a 38mm would be more suitable. We've never had an issue with "gas mix/adverse effects" on a 38mm. I guess that boils down to how much use is "extended use". There could be a disclaimer for so many things.
 
I deceide for the 38m Tial with a .6bar spring, but I'm still confuse if I need to change the spring for a bigger one or just purchase a boost controller..
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OK, Per Full race a .6 bar = 8.70 psi, so can I increase the boost with a boost controller or I still need to purchase a 1.0 bar = 14.50 psi ?
 
To the OP, thanks for starting this thread. It's helping me understand something that I will need to know for my own personal build. Rep! :thumbsup:

To everyone else, thanks for contributing. :
 
Same here. I too am about to go for a turbo build so I could use all the info there is for turbo's
 
The spring in the WG is the absolute LOWEST boost setting you can run.
Using a boost controller, you can effectively DOUBLE the output... sometimes a couple extra depending on the boost controller it self.

so, if you have a 6psi spring, with a boost controller you can get about 12-13 or so psi out of it.
if you have a 10 psi spring, you can go to 20-22ish
and so on...
 
So really, if you have a good turbo set up, with a solid piping, your spring in your waste gate spring is what really controls the amount of boost you have.
 
The spring in the WG is the absolute LOWEST boost setting you can run.
Using a boost controller, you can effectively DOUBLE the output... sometimes a couple extra depending on the boost controller it self.

so, if you have a 6psi spring, with a boost controller you can get about 12-13 or so psi out of it.
if you have a 10 psi spring, you can go to 20-22ish
and so on...

Thank you, thank you and THANK YOU for that simple explanation, B. I swear, if I didn't have to spread ye o'le kayak around more I'd rep you right now.

Question: Just for arguments sake, say you run a 10psi spring, do you need to run such high psi or is that what the max psi you run should be? I'm wondering if running a 10psi spring would work on a set up of less psi for the time being, that may be increased later with a tune.

I'm hoping I made sense on my inquiry too. haha
 
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