I was debating about making the flange at my work, and making it a little easier on myself since I am fabbing the kit. What do you guys think about a flange with a round hole mating up to a T4 flange. Obviously the round hole will overlap the T4 flange in some spots and cause turbulence. Are their any kits out there that have a round hole in the turbo flange on their hotside pipe (PTK, Pham, TTi)? I know Jordan Musser did it this way, but he never got it dynoed. I just dont want to hurt the power potential. I made a quick Pro E model to show what I mean. The yellow line is the profile of the T4 flange.

http://www.ls1tech.com/forums/attach...chmentid=31112

 

Copying Jordan Musser might not be the best way of doing things. I would get the right flange and call it a day.

 

My old TTi kit used the round hole. Yeah, dont copy jordan, he has no idea what he is doing

 

You could easily port-match your turbine housing to align with a 2.25"-2.5" round orifice T4 flange (TTI uses a single 2.25" pipe into the turbo inlet flange ... but that is definitely on the small side). Probably couldn't go larger than a 2.5" diameter round hole in a T4 flange because of the dimensions of the flange. A square or oval hole in the flange easily accommodates a 3" pipe, which is what I'd do in your shoes.

 

yes, but isnt the pipe then overlapping the flange instead of vice versa? i wanted to try to shape the end of a 3 inch pipe to make it fit directly in the t4 flange...are there any adapters out there like this?

 

I've seen ones like these...

http://www.needboost.com/part/t4%5Fi...weld%5Fflange/

I read on another broard that you can squash the 3" pipe slightly so its the correct height and then heat up the corners and thammer on them to make them conform to the T4 flange shape.

 

Go ahead and do it your way, taking shortcuts like this is whats going to cost you in the long run. A 3" pipe fits just fine with a oxy torch and a little hammering inside a T4 flange.

 

http://kak.com/camaro/headers/DSCN0838.JPG heres a pic of my old flanges that fit the 3" pipe.

 

Mightymouse pointed out that the TTi racekit uses a 2.5" circular turbo flange as well, and both 2.5" pipes merge into this one 2.5" flange. He made 900rwhp with his setup...interesting. I know that the smoothest transition is optimal, but how much better? Quicker spool by a few hundred rpm, 30rwhp more? These are the questions that I would love to have answers for. Too bad nobody has done testing on this.

 

nice header flanges pat!!

 

Those header flanges arent going to be used on my car, I've got some 1/2" ones that I will be using, would you be interested in the ones in that pic?

 

exactly how thick are those? and what material are they??? i was gonna make some myself but who knows..