I spent a good amount of time trying to come up with a brace solution for my setup. I couldn't come up with a good way to mount it to the turbo. And couldn't bring myself to weld on my brand new EFR. I'll revisit it in the fall when my turbo isn't fancy anymore.

The 323 GTR (rally homologation) also has a brace similar to the MSM. It's very rigid because it does not extend very far out from the block.

--Ferdi

Make a bracket that replaces two of the tabs that secure the exhaust housing to the supercore. Like this:

Attachment 179830

For those concerned about the addition support causing extra load due to thermal expansion, you could try using an over sized hole and a proper length shoulder bolt. The brace would support the load and the shoulder bolt would keep the brace positioned, but without restraining it. The shoulder bolt needs to be long enough to that its not tightened down on the brace. All the torque should be on the shoulder to the turbo/bracket. We used the method on our cranes in place when we have to support an exhaust component but it needs to be able to move some.

Got any pictures?

Not that I can release, but here's a quick sketch showing the idea.

Ok that's what I thought. Just emailed full race to try and figure out what material the EFR Turbine housing is. Figure I'll be able to just weld a boss on.

I forgot to add, you can use a larger hole and put a washer between the two (still keeping the gap) if you think holed needed for expansion is larger than the shoulder bolt head.

I'd be wary of those, personally. After the issues I had with those fasteners on the TiAL/Garrett combo years ago, I'm not keen on adding any stress at all to those particular fasteners. I would lathe up a couple of custom water plugs for each side of the CHRA and grab from those.

What issues were you having? Mine are inconel and safety wired on so I doubt they would loosen or break. I'd be interested to know what your experience was though.

Two more data points in support (har har!) of turbo support braces.

My LeMons car has done ~45 crapcan endurance races. It runs the stock Miata manifold, flipped upside-down, then braced with angle iron bits like so:

https://cimg8.ibsrv.net/gimg/www.mia...5eda64dd12.jpg
It's a little hard to tell, but that erector set you see above holds the weight of the turbo so the manifold is pretty much along for the ride. The manifold had ~120k miles on it before it was tasked for turbo duty. FWIW, the car is no slouch and is at the pointy end of the crapcan field.

When I built a different Miata, the green NA crazy ass dual purpose car, I had a more, uh, discreet brace made. It picks up a boss welded onto the turbine housing and ties it to the block:

https://cimg7.ibsrv.net/gimg/www.mia...e209d2bfd2.jpg
https://cimg8.ibsrv.net/gimg/www.mia...f49a4159c5.jpg
This brace is made from stainless rod. The thinking with this geometry is that it will provide just a bit of "give" in the direction of the manifold's (304 weld el w/ short-ish runners) thermal expansion, acting like a very stiff diving board.

I've said it before but it bears repeating: the idea behind turbo support braces is a little different than "crane"-style supports - a rigid brace not only takes up the turbo's mass but also raises the natural frequency of the turbo/manifold/dp assembly so that it doesn't get shaken to pieces. Many factory turbo cars employ rigid braces. When done correctly, the brace picks up the turbo at the turbo+dp's center of mass. If you want to get super fancy, you can include springs to take up the thermal expansion a la AMG CLA45.

You'll see cranes used on race cars with long-runner manifolds; the idea being that the long runners will tend to grow more due to thermal expansion. The crane doesn't raise the natural frequency. It is solely to support the turbo's mass but allow two degrees of freedom for thermal expansion.

Wow, that looks amazing. I have been waiting for years to finally see pictures of how you did that.

I've refreshed that article like 60 times waiting on updates. Is that car complete? Where can we go drool read about it?

While thats fantastic work, I need a solution that can be posted and bolt right onto most peoples cars. The water ports are a great idea.

Lots of details in prior posts, hustler had the same issues. This was on the Garretts with TiAL housings, not on the EFRs.

There isn't really a bolt on solution. You can try the water port idea if you don't run water to the turbo, or try to make a bracket that goes under three or so of the turbine-center housing bolts. Neither are ideal since they're loaded in single shear.

Mine were safety wired, and I believe also inconel... they loosened. Not enough to come out of course due to the safety wire, but they lost torque and the turbo was able to rotate.

Reinstalled with resbond and new safety wire, we'll see if that works.

But based on that, I 100% agree with Andrew here. Wouldn't put anything else there.

It rotated out of the fleet but it's still around.

Thats exactly what I had in mind for the boss welded to the turbine housing. I need to find something that will deal well with being welded to 347

Funny enough, Tial only ever encountered the loosening bolts on... Miatas. No other application had issues, if I recall. The Williams Formula 2 cars, maybe. But that was due more to heat (those manifolds/turbos were completely encapsulated and saw no cooling air). Those two situations are what led Tial to switch to inconel bolts on every turbine housing they sell (!).

Which should prompt some thought - what is it about the Miata that makes it so hostile to turbo (and other) bits? You already know the answer...