Thread: T28 External Waste Gate Dump? FWD

Yah, they have redesigned the GTi-R one with miter cuts...

I'm sorry, I must not be taking this in fully.




If the mandrel doughnut achieves the same CLR and bend radius, then why would the only "right way" to do it be with a pie cut or expensive cast piece?

Going back to my point on faster production time and a cleaner appearance. I feel that with the mandrel doughnut it would be much less fab time involved with a fraction of the welding time. As long as you have some type of belt sander to obtain the angles you want on the flanges.









Versus this extravagant piece of work




I personally like the look of the mandrel bent doughnut better than turbofx's final product. Now we all know that functionality is the main deciding factor for most of us. But if you are saying that both methods achieve the same functionality, I see an obvious choice....




And this last portion of this post keeps changing on me It went from 40 WHP to being unknown. Now to 10% whp gain.

But seriously, has there been a dyno yet?



-Seth

personally I would send my manifold to andreas miko and have it modified for a external gate. Then tak weld the flapper door shut. The gtir setup gains 30-40whp when run external gate. I believe dre still charges around 300 for his welding and porting magic.

^ thats a good idea too

Hmmm i would have never have guessed that great of a gain! i have to say, " The Dash" is a great forum to belong to! Totally different environment than DSM forums. Very chill, and very helpful.

I don't have my back to back dynos but I made 302whp@ 15psi internally gated. I made 342whp after dre did his porting and welding work. I have seen the gtir setup make 320whp on a external gate. the Most I have been able to get out of the stock gtir setup was 300whp 300lbft @17psi on a stock gtir motor.

They had mandrel bends available with 1D bend radius. They couldn't even begin to clear the alternator with them, so they had to do the pie cuts to get an effective radius of about 0.70D. Look at how small the "hole" is in their resultant pie-cut doughnut shape. Way smaller than the 1D hole of those metal doughnuts, wouldn't you agree?

Divorced wastegate gains changed in my post because I thought I knew they made about 12% gain, then I was reminded that tubular manifolds versus log make about a 12% gain and I thought my memory had confused the two, so I made an edit. Then I was reminded that both modifications result in about a 12% gain. So I edited again with 10% to be conservative.

Modifying the GTi-R manifold for external gate is also a popular option worth considering as mentioned by others.

I have an externally gated GTI-R manifold on the way. I may actually put the stock intake manifold back on, and get some new numbers to see what kind of difference there is, as that would be the only change. I made 320/300 with my internal wastegate gti-r manifold, spiked to 19psi and settled at 16psi.

I was interested in the turbofx bellmouth pipe when I got everything sorted out. It would be nice to have some better flow that then stock jpipe provides.

Ehh that makes javier from turbofx's explanation make sense to me now. It doesnt seem to me that the alternator would be the major clearance issue with the doughnut as the A/C, i guess ill find out soon enough in my own trial and errors

Also, where did the figure of 12% gain come from?

Very few people have bought turbofx's product, yet all i hear and see is negative criticism about how they would have done it and yadda yah. For the past 8 years i have been messing around with sentras no one company has come up with replacement for our restrictive jpipe and successfully mass produce it for our community. Here you have a guy who is trying to fabricate a quality product for our/his community and do it relatively cheap and mostly all i can see is jabs at the product. Now i wonder why our aftermarket support sucks, and why all the companies who tried to make profit tending to our needs has gone out of buisness. Stop nit picking sheesh in my opinion this is what hes competing against at the moment



for 300 or w.e it is how can you go wrong?