[Stee]

Is there anyway possible to use a larger wastegate flapper with a proportionately larger exhaust hole? I see everyone boring the hole out, but only millimeters larger. It seems this would absolutely nullify any boost spiking issues whatsover.

[Snax]

First off, creep and spiking are two different things. Creep is when the open wastegate cannot flow enough exhaust gases to keep boost pressure from rising. Spiking occurrs when the wastegate control system lags behind the buildup of boost and has nothing to do with the flow capacity of the wastegate itself.

From the photos I have seen however, I'm guessing the hole is around 20mm. Taking it from 20 to just 21mm nets you 346 sq mm from 314 sq mm. which is a 10.2% increase in area (and presumeably flow capacity) for just a 5% increase in diameter. I'm guessing that people are getting at least 2mm out of boring however for 380 sq mm and 21% more flow over stock.

That said, I've been led to believe from others on this board that the turbo is pretty much maxxed out at that point anyway. Enlarging the wastegate further than the stock flapper would allow is simply not worth the effort.

I don't really know, but it's plausible.

[Invisiguard]

they flow plenty good when ported right, Ive had 2 so far(one Deadbolt, one my own) with no probs 8)

[Stee]

Thanks for the info Snax. My reason for posting was due to reading that porting simply wasn't good enough. Maybe the person didn't remove enough material. Oh well.

[blueballs]

Correct! Also remove it at an angle beneath the wastegate. The wider it is below the wastegate, the better the flow.

[b_boy]

Resistant is the proportional to radius of the wastegate hole to the 4th power. Thus only a small increase in the radius will amplified exponentially.

Poiseuille's law:
R = (8hL)/Page Ranking^4

P = pressure, n = mean flow velocity, Q = volumetric flow rate, L = tube length, h = fluid viscosity, and r = tube radius

Same reason going from 2.5" exhaust to 3" is huge in terms of air flow.

[Xman]

now your college tuition is really paying off.

[ss3homer]

Dude, you're awesome Snax!