When you have the right tools, nothing is really that hard. Making a downpipe, is what I’ve dreaded the most since I started turbocharging the car. Between the irregular shape of the turbo outlet, and the tight confines of the steering column and frame rail I was quite fearful of screwing up and wasting time and materials. Hammer forming the turbine outlet was certainly the most challenging part.
And as you can see, the 2.5″ tubing I used did not offer enough circumference to fill the turbine outlet, so I had to flare the end by combining it with another section of tubing. The CX-Racing HKS clone manifold is pretty popular, and if you are here looking to build a similar downpipe, the materials I used are: 3x 90 bends, 2x 45 bends, about 1ft of straight tubing, the flanges, the flex pipe and of course some 02 bungs which I have yet to fit.
With the exception of it’s proximity to the firewall (it pretty much touches the firewall as it bends out of the outlet) I am very happy with the fitment. It’s about 0.5″ off the floor, parallel to the frame rail and a safe distance from the steering column. My plan is to ovalize the section that is too close to the firewall, and hopefully not beat it very hard with a hammer afterwards. And then I’ll wrap the entire thing in a fiberglass header wrap, and maybe even add some aluminum reflective tape to the firewall.
And that’s how it looks now. I still need to make a brace for the AFM, and Ryan found me a Blitz recirculating valve, but I’ll probably add that later… maybe the same time I add catch can. Did you know large Sapporo cans are steel??
That’s pretty cool Q,
Did you post this before or after I saw you?
Nice work, looks like you took your time and made it fix right.
I’ve seen some people put a small divider to separate the wastegate flow from the main exhaust for a few inches, supposedly to ease any turbulence from the two flows merging closer to the wastegate flapper.
That might be the only thing I would add, just my totally Theoretical turbo knowledge, from a guy who doesn’t like turbos 🙂
Haha
Posted before we clashed at MOPAC… but it’s not like I expect anyone other than me to read here. A divider sounds like a good challenge… and something to slow me down even more. Bah. I’ve seen metal gaskets that had a divider built in… but strangely never for T25 flanged turbos. As I said… one missed auto-x already, getting really damn impatient.
Looks good Q, only thing I can criticize is it looks a little tight to the unibody rail, if you have firm engine mounts might not matter….
Neil
I do have some stiffer mounts… I guess if it bangs around I could add a torsion link or something. It’s full welded now though… and actually pulled away from the rail a bit during that process. Good? Maybe not because now it’s closer to the column. I’m still figuring out how slow and careful I need to be when adding real heat.
SAPPORO CANS ARE STEEL!
me gusta.
Did you weld this up yet?
Bolt it to the turbo first so the flange dosen’t warp with the heat.
Oh, ya. Nevermind.
Bend it back with your long arms.
I did use my spare turbo for that purpose. But welding the full thing on the car would have been a real PITA.
It’s damn strong though. 16 gauge is thick? Dunno… but it’s what I used. I ripped the vice off the bench when I only had it tacked together and was trying to tweak it. It’s pretty heavy. I kind of wish I went with something thinner.
I wonder how much fatter the car has gotten? Probably a solid 40kg despite the removal of a few other items.