Downpipe choice

[Master Z]

I have a ‘97 Spyder GST that was completely stock when I bought it. I upgraded a couple of things and now I want to change the stock exhaust. I bought the HKS carbon highflow exhaust but it doesn’t come with a downpipe. Heard that only 2.5" downpipe fits with it, that it’s made for stock downpipe or at the same size as stock. In the future I’ll get a 16g turbo so I’m looking for a downpipe that will fit on both turbos and is it possible to still add a bigger downpipe? Would like to delete the restriction of the stock downpipe and improving airflow from the exhaust to gain as much power as I could from this exhaust upgrade. Which downpipe would you recommend me for this exhaust?

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[pma1123]

You'll be most likely re-using the O2 housing off your T25 to go to a 16g in the future, so the front flange and location stays the same.
I'd just stick to that goal of making it 2.5" turbo to tip for what you are doing.

I don't know what kind of Megan racing type stuff is for sale anymore but that will ruin the street cred that comes with an HKS exhaust. But it could be an option; looks like many of those downpipes have a 3" outlet.

Do you drive everywhere on exempt private roads like me? (cat converter needed?)

I'm into buying 304 SS elbows, straight, flex section, flange off amazon and building my own stuff; so that is a very solid option to get the exact downpipe you need, constructed the way you want, fit to the car, in the materials of your choosing.

Do you have ability to mig weld/know somebody that could help you build/modify your way to the exact custom downpipe you need? Your car could be driven with an open O2 housing a short distance to your buddies shop...