exactly how bad is the greddy downpipe?
 

OK, I know that without a doubt some gains will be seen by going to a better/larger downpipe, however will the stock greddy one support around 185-200 whp? That's all I'm really shooting for, and it would be nice to get there and still have a semi-smog legal kit (or at least be able to revert quickly if needed).

Pretty bad, it's meant to maximize the power of the stock exhaust. It's a big limiting factor. That setup could net you 180hp and could probably be a decent 220hp setup with a quality 2.5" turbo-tip exhaust system and only an extra psi or 2. Along with the injectors to handle the extra power of course.

I'd go one worse than that, Curly, and say that the stock Greddy downpipe is only meant to physically connect the turbine to the stock exhaust. It's horrid.

OP - You may attain your goal on the stock downpipe, but you'll get faster spool with a good downpipe and probably make the same power with less boost (read: stress) on your engine.

https://www.miataturbo.net/attachmen...ine=1321403123

got it. sounds like it may be worth the time to just swap on/off the downpipe when it comes to inspection time.

They won't notice the damn downpipe, will they? I'm guessing you're in California? (aka: put your location in your profile)

With the FM Greddy heat shield, they won't be able to see it.

I never had a problem with the visual inspection while running a 2.5" TurboTony pipe. It's not as though the tech has a high-resolution image of the pipe that's supposed to be there.

+1 to the above WRT inspection. If the tech can see the downpipe and actually knows what he's looking at and cares enough to fail you for it, you were probably going to fail anyhow.

Put your location in your profile bud.

exactly -1.231245632

This. A REAL downpipe transforms the GReddy kit dramatically.

hey guys, was wondering who all makes upgraded DP's for the greddy turbo. i like to shop around a bit before i make a decision.

Right now I only know of artech and begi making replacements... not sure if tonyturbo is still doing it.

I plan to get a 2.5 from artech when the time comes.