I feel like the oil return flange is a good place for support but i wont **** with it for fear of fires.

Lots of thinking to do.

Dann

 

The nut behind the wheel?

 

On my big turbo, I drilled/tapped and installed an 1/4 NPT to 4AN oil fitting to feed oil into the turbo, then built a hanger to hold the turbo up by the bolts on each side of the oil fitting. So the oil fitting is not using those bolts anymore, so no risk of fire if those bolts did vibrate loose.

 

Another great idea but not one I can post to people who often already have a turbocharger and are only buying the manifold/downpipe kit.

I genuinely feel that if good NB customers keep coming Im going to just switch to Andrews manifold/efr for track applications.

Dann

 

What about getting a custom turbo flange cut and bracing directly off of it with big hardware to the block?

 

You could just use like 2 bolts off the inlet and/or downpipe flange. Like how the OEM subaru stuff is.

 

Have you ruled out a material change in your manifold manufacturing? Or a design change? I think a larger radius of material where the flange meets the runners is the first thing to do. A tight radius is a big stress riser, and this can be altered when it's welded to put a bigger radius.

After that you could weld a pad of metal to the pipes at the collector near the flange, and then weld a brace from the flange to the landing pad to essentially triangulate the flange to the collector.

 

I'm sorry pat. I've already taken this advice (radius, brace to manifold from flange) and am implementing it. It's simple, easy, and I think youre right

in addition to this a nice block brace wouldn't be a bad idea. I had considered bracing from the downpipe flange also leafy. However I think the turbo flange on this manifold is in a better spot to use the engine mount bolts.

Dann

 

Oh, I figured you wanted to retrofit a solution to existing setups, my bad. Yes bracing off the turbine inlet flange is legit. Might be your best bet. That, and using better material - mild steel is really not cut out for turbo manifolds.

 

I gotcha, sorry for sounding rash, not my intention.

For the brace, I would try something a lot like what mazda did. I think the direction the turbo is most likely to vibrate is up/down. The MSM brace can support the turbo, but also can bend the most in this direction. So while it does support the part, it can tollerate some flexing without immediately cracking/failing. I think that's important for it to last.

 

Youre suggesting only 347 SS?

 

Good luck finding 347. It was hard enough finding 321SS. Thats what I made mine of.

 

We can buy billet 347 collectors and steampipe style bends in 347ss locally, but $$$$ and the local MX5 community is unlikely to justify the expense.

Dann

 

Ok, After some brainstorming I want everyones opinion on this.

First a picture of the fitment of the manifold/downpipe as it sits.




Next a close-up. In this image the red addition represents an addition to the downpipe flange. This downpipe flange is already custom, and I have them water cut for each manifold, so its not a problem to have their design modified.

The orange represents a brace which I would make, something similar to the design shown in the final picture.






Here is the downpipe flange, shown with some additional material I would have designed into it, of course the hole in the added part would probably be slotted. The red added part is the red part in the 2nd photograph.





And finally, the style of brace I think is cheap easy and workable, again the hole would probably be slotted, and of course a longer engine mount bolt would be needed.





Ok everyone, tear me to shreds.

Thankyou,
Dann

 

I did a google search and found a pretty clear picture of the MSM brace. It looks to use two bolts going to the engine mounts with tabs that are bent at a 90, then it stretches out to the mounting point, where it again is bolted in at a 90* angle. So it can support, but still wiggle without just breaking.

Whatever design you do, I would have 2 bolts going to the block, and I'd have the brace able to bend/flex in the up/down direction at least some. Otherwise it's going to put a bunch of stress on the things when heat causes thermal expansion and your brace has no give. From what I can tell your design tries to put a bracket in bending forward/back (not up/down), in single shear at the downpipe/brace connection, all supported by 1 bolt, with a direct point to point connection. I don't think that's the best.

 

I can easily put a 90* bend into this design, And I think you're right.

What about a simple 'L' bracket bolted to the flange design, and a simple 90* bend added to the bottom bracket?

 

Ok so..


Red is extended flange with hole as above.

Green is MSM style diving board brace, and blue is a stout 90* bracket so that a diving board style mount can be made to work.




How about now?

Dann

 

Why not modify the flange so that it has a flat bottom that you can weld a boss onto and brace it similar to JKav's elegant solution:

... the brace mount points would be different but there are a lot of options available on the block

 

Its another potential failure point. I think ive figured out a sheetmetal one piece brace that will do the job while adding just one bolted connection.

 

.