Considering a External WG setup. What are the benefits from going external WG?

-I understand that the ext. wastegate can control boost better becuase of the much larger ammount of gasses that can be dumped. (Thats really only necissary if you run a BIG turbo on low boost..)

-Maybe less backpressure/restriction because of the dumped gas not going through the turbine? And even better if you dump it to atm. As the whole exhaust will be less restrictive..

-Abillity to use T3 flanged turbos.. Bigger exhaust housings/wheels and again less backpressure/restriction? Are T3 turbos (fx. GT30, GT3071R) really better than the T28 alternatives because of the bigger/ better flowing exhaust housing??? Better matched turbos?

-Some would say that just the sound of external wg is benefit enough...

Am either going to use the GT3071R-WG or the "real" GT3071R with an external wg setup.. Leaning towards the last because of the above mentioned reasons..

Am I wrong in any of the above reasons?
Did I forget something?

Please feel free to correct/comment on this..Dont really know if its worth going external????

what noise does an external wastegate make? I'de stick with internal. I dont see why you would go for externa when the turbo you want is offered in internal which your car is alredy set up for. To run a t3 you need a new mani, downpipe, intake pipe, and an externa gate. For the money you would spend on that stuff i can think thing that cost half as muhad would be famore benificiary then an external gate. IMO

This is probably the first time I have to agree with Yingtiry. By the time you spend the money on an external wastegate, you will not benefit as much as you think. To really hit the maximum boost pressures on the GT30, GT30R, etc, you will probably pop the motor before maxing out the wastegate. There is no true benefit from switching from internal wastegate to external wastegate with a factory manifold. Sure, it will hold better boost pressure, although the internal wastegate that is included with a GT series turbo, is plenty enough to handle the power. IMO, it's not worth it.

I run an external wastegate on my car, but I am running a T3/T4. It sounds badass, but I wouldn't go through all the trouble you want to just for the sound.

Corey

I wasnt going to do it for the sound.. (That would only be a little bonus)

If going with the external setup it would be because of the bigger turbos this would allow me to run. Gues this would give me less back presssure/restriction and the same ammount of power @ lower boost.
(+ the other reasons I stated above)

And the GT3071R-WG are not "the same" turbo as the GT3071R. In the T25 housing the wheel is 56,5mm and in the GT30 its 60mm. Would have guessed that the GT30 exhaust housing was much better flowing than the smaller T25 housing.

But if guys say its not worth it..
That was what I wanted to know really :)

Was thinking of a setup much like this..

http://img.photobucket.com/albums/v242/kristiankra/gtir/IMG_2906.jpg

Wouldnt be that expensive. I need a new turbo anyway..

Well I'm not saying there isn't an advantage, but it's not worth your money. I'm sure others will chime in, but you can upgrade to a GT series turbo without upgrading to an external wastegate. If you have money to throw away, do it. But it's going to cost you a little more than parts. IE: Fabrication on your manifold, making sure you have extra room to extend wastegate, etc.

Corey

Was thinking that it might actually be better for the engine (std. internals) to make 400+hp on a big turbo/ ext. WG setup than pushing all that power through the little GT25 exhaust housing..
Wouldnt the first option cause less heat and stress on the engine?
Is there any thruth in that?

Everybody has an opinion right... so make of it what you will.

From a sound point of view I think an ex WG that is NOT tied back in to the exhaust sounds terrible, others as you have read think otherwise. The turbine manifold absorbs and distorts the exhaust in to a loud rush of noisy air when it opens IMO. Go ride with someone with un un-muffled ex WG and hear for yourself.

From a performance POV the internally WG'ed T25 will support up to 400WHP without a problem and is easier (read: less expensive) to plumb.

If you are planning on pushing more than 400WHP you may want to consider an ex WG and go with the T3 flange since it flows better than an ex WG'ed T25.

In simple...
Internally gated T25 is better than internally gated T3
Externally gated T3 is better than externally gated T25.

By going to a "bigger" turbo you can/will reduce back pressure and make more power per psi of boost since you will be increasing your VE. As far as reducing heat and stress on the engine... boy that would be hard to measure. I would tend to think the engine would be better served by keeping the oil clean than by going with a larger turbo to reduce heat and stress. Plus you would get better response by going with a properly matched turbo. I mean your thinking is right... it's just that you are talking about a fraction of a percent in gain (reliability/reduced stress) (IMO) and would be better off with a properly matched turbo.

How much power do you want and how do you plan on driving your car for the most part? From my experience REALLY knowing what you want is the hard part... Once you do the rest is easy and there are plenty of smart and experienced people to help you get there.

Peace.

I wasnt going to do it for the sound.. (That would only be a little bonus)

If going with the external setup it would be because of the bigger turbos this would allow me to run. Gues this would give me less back presssure/restriction and the same ammount of power @ lower boost.
(+ the other reasons I stated above)

And the GT3071R-WG are not "the same" turbo as the GT3071R. In the T25 housing the wheel is 56,5mm and in the GT30 its 60mm. Would have guessed that the GT30 exhaust housing was much better flowing than the smaller T25 housing.

But if guys say its not worth it..
That was what I wanted to know really :)

Was thinking of a setup much like this..

http://img.photobucket.com/albums/v242/kristiankra/gtir/IMG_2906.jpg

Wouldnt be that expensive. I need a new turbo anyway..


believe me the 56.5 mm wheel can produce more then enough power to put more then one hole in your block. When it comes to turbos bigger is not always better. you generally want the smallest turbo capable of producing your desired power so your not stuck with 2 seconds of lag.

believe me the 56.5 mm wheel can produce more then enough power to put more then one hole in your block. When it comes to turbos bigger is not always better. you generally want the smallest turbo capable of producing your desired power so your not stuck with 2 seconds of lag.

And again, agreeable point. BrianB also has a very well perspective. An internally gated T25 vs internally gated T3, etc. I'm sure you've heard if before, and I hate to beat a dead horse, but it all depends on your goals.

Corey

And again, agreeable point. BrianB also has a very well perspective. An internally gated T25 vs internally gated T3, etc. I'm sure you've heard if before, and I hate to beat a dead horse, but it all depends on your goals.

Corey


Yes that is most important thing. building somthing to your goals that you like. If you feel strongly about having an external wg go for it. But if your working within a budget like most of us it may not be the best idea when it comes to getting the most bang for the buck.