Modifying NB stock cast manifold for turbo?
 

Hey,

I am curious if anyone has turned a stock NB cast header into a turbo manifold. The manifold with a pre cat looks like it might be too much hassle to bother with but the non precat manifold looks quite interesting and is angled far enough back it looks like it should clear the a/c though the turbo might end up being low enough that it interferes with the radiator hose. Thoughts?

EDIT: Actually the precat version might work out better as I am guessing the exit into the cat is round it might be possible to weld an elbow to the outlet and fit a turbo flange and then just cut off the extra precat flange material. It could be a very straight forward option for v band entry exhaust housings.

Manifold with precat:
https://www.miataturbo.net/attachmen...ine=1399107216

Manifold without precat:
https://www.miataturbo.net/attachmen...ine=1399107216

It is possible but no one has done it because it would be a headache and require as much or more work than making a new log manifold from scratch. It would also be much harder to weld and much more prone to cracking. It would also put the turbo in an awkward location.

Someone has done it with the stainless welded header. It still doesn't make a lot of sense unless you live in a third world country where labor is free and resources are scarce.

You're wasting your time thinking about this. With the numerous manifolds on the market that have taken into consideration all of the logistics of turbo placement, you're posting eggplant.

Don't forget the steering rod that it would put the turbo right into.

There really is not point to re-invent the wheel here. Either buy pre-made or get some weld els and make one.

These things for miata's are so easy and so cheap now, that it just blows my mind that people STILL want to figure out way to make it easier and cheaper.

I suspect QCB will be here shortly...

Fair enough. I guess if it was reasonably easy others would have probably done it before.
RHD so the steering rod isn't an issue. I am a novice at welding and fabrication so I was curious. I guess I shall just get some more practice in with cutting and fitting bends until I can put together an ok basic manifold. Regarding collectors out of a T2 or circular flanges (like on the TD04, 14b, 16g etc) would one be more straight forward for a novice to make? Using a T2 might be more straightforward overall as it would be possible to use an off the shelf turbo elbow/dump pipe. Matching the exhaust side of the turbo looks like more of a challenge than the turbo flange.

NB2 is better. Maybe JKav or Dave Coleman will post up about it.

Frankenmiata - Turbocharging > MotoIQ - Automotive Tech, Project Cars, Performance & Motorsports

:P Ok, ok. Bad idea.