Im just curious about the pros and cons of external and internal wastegate. Just because I see more external than internal wastegates. Searched but got nothing. THX

 

 

You can pass smog inspections in some states with internal

External is better for bigger power

but whatever toots your balute

 

For performance, always go external.

Many problems can be assosciated with internal WG. They always spike, creep, and hard to achieve a stable boost. After aging, the flapper doors could be stuck from corrosion, heavy carbon, etc... They are simple and cheap though. You don't have to buy an extrenal wastegate, and it eliminates another hot exhaust pipe (no WG pipe). There is also less clutter in the engine bay.

External setup are much more consistent and does the job better. Much easier to get a stable boost and control spike/creep. That depends on your WG choice though. On larger turbos, internal wastegates aren't even an option as to why you mostly see external wastegates here on Honda-tech.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">They always spike, creep, and hard to achieve a stable boost</TD></TR></TABLE>

Not true. At conservative levels of boost they work flawlessly. My internally-gated T3 wouldn't have been used on a Mercedes if it was crap.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by beepy &raquo;</TD></TR><TR><TD CLASS="quote">

Not true. At conservative levels of boost they work flawlessly. My internally-gated T3 wouldn't have been used on a Mercedes if it was crap.</TD></TR></TABLE>

I never said all internal wastegates are crap. I am sure we all know that any turbo car from the factory uses an internal wastegate, and if they don't work well it wouldn't be on those cars, right

I personally have an internal wastegate, and it's crap. This is from a Garrett GT28RS. Generally, most internal wastegate suck in the performance perspective. You can't argue that.

 

does neone know if the greddy 15g comes internal or external???

 

most greddy kits come with internal gate

 

Most dont understand the fundamental flaw in internal gates, thus the reason why they are often said to "suck". Basically your internal wastegate is normally found on a stock turbo'd vehicle, or a replacement to your stock vehicle's turbo. What does this exactly mean? Well it wasnt calibrated for the lack of back pressure found in your average free flowing 2.5-3" exhaust. Its a very simple thought process. if the internal gate is setup to expect some sort of force apposing it, and the force is significantly smaller, the arm will swing open more easily and not work correctly. Boring out the turbine housing solves this problem but allowing the pressure equilibrium.

Now, theoretically speaking internal WG turbos will be best for spool up time because they are placed off the turbine housing so its redirecting any actual exhaust waste and the pressure is there as soon as the turbo begins to spool which will allow for the fastest spooling and best boost control.

Simple solution, weld your external WG directly onto your T3 5 bolt flange. You get the best of both world. Priority given to your wastegate, and a wastegate designed for free flowing, low back pressure exhaust systems. Win win.

Again, you can make internal WGs work just grand. mine holds 10-11psi within 1psi which is just fine for me seeing the WG came with my $150 turbo. Just took $10 worth of heavy duty sanding bits and 15 minutes of my time boring out the turbine housing.