Turbo Guys - Tial Wastegate question

[WERK I]

My stock wastegate just crapped out. I'm considering going to the Tial 40mm unit. My questions are;
1.) Are there any special mounting/fabrication requirements?
2.) Is 40mm the correct size?

My engine has the following mods;
B&B Headers, Web 158R grind(SC type), Kokeln IC, twin plug, K27
Thanks

[tsuter]

I would not run anything larger than a 40 for sure and I would then consider using a supplemental boost controller to slow the opening.
Mine is a 35mm for a 3.0SC with add on turbo and it is just bolted onto a welded in flange. I have a TurboXS mechanical boost controller (not pictured) from slowboyracing.com Nothing special.

[rfng]

The size of the wastegate controls the exhuast energy bled off. Once you get above 1 bar you will need a bigger wastegate as the small gates will cause boost spikes and have trouble regulating boost levels.

[beepbeep]

Originally posted by rfng
The size of the wastegate controls the exhuast energy bled off. Once you get above 1 bar you will need a bigger wastegate as the small gates will cause boost spikes and have trouble regulating boost levels.

Errrr....40mm is probably enough for 600 HP car, so i don't get your point. When you boost more , more gases flow trough turbo itself and not trought the 'gate...so it's not as easy.

As i said 40mm is plenty sufficient and is little bit smaler than OEM 930 wastegate that is used on real mega-powered cars.

[hobieboy]

I thought most are recommending the 46mm Tial for 930?
Particularly with an external boost controller, leakage shouldn't be an issue.

[beepbeep]

The smaller turbo you have with more backpressure the bigger wastegate you need. That being said, external wastegates are almost always very over-engineered and can sustain flow well past the requirements of engine they are bolted to.

Internal wastegates can be little streched on the other hand, as they need to fit inside turbine housing and i have seen examples of boost runaway on internal wastegates after addition of free-flowing exhaust system. (It's uncommon though). But then we are talking wastegates 20-30mm in diameter at best.

I'm quite certain that he will never see any problems with 40mm wastegate in his application. It's not good to have huge closed cavities bolted before turbo anyway...

[rfng]

Originally posted by beepbeep
Errrr....40mm is probably enough for 600 HP car, so i don't get your point. When you boost more , more gases flow trough turbo itself and not trought the 'gate...so it's not as easy.

As i said 40mm is plenty sufficient and is little bit smaler than OEM 930 wastegate that is used on real mega-powered cars.

Obviously you've never run on engine with a lotta of boost. There going to come a point when the size matters.

When the gate opens exhaust energy is bypassed or bleed off from the turbine, causing the impeller to slow as there is less exhaust engine available to spin the turbocharger. This is how a gate controls the boost level being fed into the engine.

At some point a small gate due to the small valving begins to have trouble bleeding off enough exhaust to slow the impeller. Causing the boost level to spike or inconsistent boost levels.

That why they sell different size gates depending on engine capacity and boost level. But then you knew that I suspect.

[beepbeep]

Originally posted by rfng
Obviously you've never run on engine with a lotta of boost. There going to come a point when the size matters.

When the gate opens exhaust energy is bypassed or bleed off from the turbine, causing the impeller to slow as there is less exhaust engine available to spin the turbocharger. This is how a gate controls the boost level being fed into the engine.

At some point a small gate due to the small valving begins to have trouble bleeding off enough exhaust to slow the impeller. Causing the boost level to spike or inconsistent boost levels.

That why they sell different size gates depending on engine capacity and boost level. But then you knew that I suspect.

Err...yes i know how wastegate works. What i'm saying is that 40mm is plenty enough even for 930-sized engine and even bigger. I'm also saying that smaller/more restrictive turbo needs bigger WG beacuse it gets saturated earlier.

P.S. Weren't you a guy who want's to sell turbo kits to SC crowd and find diverter/BOV valves "unnecesarry"??

[WERK I]

I chose the 46mm Tial for a few reasons. I wanted a wastegate that is the closest match for the factory wastegate. It had to mate up to the B&B headers with the least amount of hassle(e.g. exhaust fabrication). It had to overcome the current wastegate location that is far from ideal. The 40mm does not meet any of these requirements. Finally, most if not all engine tuners recommend the 46mm for the 930.

[rfng]

yes I am.