Project Turbo
Turning Up The Horsepower
Spin the fan and get out.
-With the Up-pipe fabricated and in place, I now have to turn my attention to the lower half of the exhaust system.
-This stage of the project has been in stasis for a few days, no, weeks, no, months. The reason is purely time, until now I had to finish up my last year of high school, and get myself into a college. With school over and all my college taken care of, I finally have some time to work on my turbo project as well as Andrey's exhaust system. I'm getting some cool things done for his exhaust, including a new header, but not to spoil the surprise, you'll have to wait until it is finished and I put up the report on his Stage 2.5 UHP exhaust.
-I had to make my own flange for this part of the exhaust because I wasn't able to locate a factory one I could just cut out and use. To accomplish this, I used a peice of metal that I cut out of a chunk of angle steel, not too sure what gauge but it is very thick, possibly 3/8". First I cut a general dimension with the cutting torches, then I marked the bolt holes and drilled them out in a drill press. After I had all the holes done, I traced the outline of the turbine housing casting onto my plate and took out some chunks with a chop saw to make everything a bit smaller and a bit cleaner. Unfortunately, my original peice was a bit on the small side, and one edge had to be left as is, with all the torch marks, not too clean but it'll do the job. Maybe later on if I'm bored I will smooth them out with an angle grinder.
-To make the holes for the gases to pass, I took some measurements and cut two round holes, one is 2.5" and one is 2" for the turbine side, and the wastegate side, respectively. The two holes overlap and I took out the shap points with an angle grinder.
-I then cut a peice of tube that was the height of the studs and welded it into place in the big 2.5" hole, this will be the main pipe and I wanted a straight section that was the height of the studs so that I wouldn't have any troubles getting the nuts on and off.
-For the wastegate I had two options, I could merge the two chambers into one pipe and have it carry the gases to the exhaust, or I could have two seperate pipes which I could then merge somewhere later on down the line. I decided to go with a single merged chamber simply because it makes my life easier, I wont have to run two pipes out side by side. So I cut a tube to fit into the hole I had made around the wastegate, I cut a peice of 2" pipe into a triangle and cut out one side with blowtorches. I cut a slit out of the big pipe as well with the blowtorches, the two open side sit together and form the center chamber. As far as I know, this setup wont perform differently than a seperate pipe with a Y farther down would.
-Then I had to cut up my nice mandrel bent J-pipe, I needed a 90 degree down turn to take the pipe out the factory location, so I took a half of my J-pipe and welded it onto the end of my other big pipe. I also had to cut some material out of this bend to allow the end of the chamber to be formed.
-In a turbo setup, backpressure caused by sharp turns and shap edges only has a minimal impact on performance when it is in the tubing before the turbine. However in the tubes that are after the turbine, you want to have as little backpressure as is possible, to create as big a pressure differential as possible between the two sides. Thats why I ordered this nice J-bend from Jegs, it is mandrel bent so it stays perfectly round and smooth through the whole curve, this reduces by far the amount of backpressure in a system, not to mention that I'm using some fairly big 2.5" tubes for my whole setup, with a 2.5" racing catalytic converter and virtually no muffler to speak of. I hope to be rewarded with some quick spool-up and decent turbine efficiency.
-The following pictures show the pipe after I welded it all up. I still havent really cleaned it up much, and I still need to finish off the bottom end and paint it, keep visiting my site, I hope to update it again soon with that and more.
