Summary of latest turbo stud mounting recommendations?
 

Rather than wade through pages and pages of discussion, can someone <cough! Savington!> post the latest best practices?

I know the best recommendation is to use Vbands. :)
If not that, then 10 mm inconels.
Next are 8 mm inconel studs.

Torquing the stud into the manifold, (assuming they don't bottom)?
Resbond? Where? Stud to mani interface only? Also stud to nut interface?

Now what about stage 8's?
If they don't fit, do those funky one-way toothed washers FM sell help?

How susceptible are the 5 studs in the back of the turbo?
Would non-inconel SS work a lot better than regular steel?
Funky FM washers here? Resbond?

Anyone know a torque value for 8 mm or 10 mm studs?

10mm inconell studs preferebly a setup where you can get some extra clamp group lenght in them to lower the effective spring rate of the stud. I've used ether Nordlock or stage 8 with Inconell and both worked with Resbond.

Absolutely nothing else has worked for even a single half day on a track without the inconell for many years of trying different things on multiple miata turbo setups.

Is drilling and safety wire worth the effort?

Drilling and safety wiring what exactly.

I don't drill or wire. 10mm inconel studs from Full Race. A little touch of Resbond. And don't use a turbo blanket.

Funny you post this now, I just read through almost that entire thread yesterday. The inconel naysayers sure shut up damn quickly once Savington proved the solution. Amazingly another vendor stated inconel would not work and now carries inconel studs. This same vendor has stated a number of times that tow hooks should be removed and are unnecessary so I suspect they don't even know what a track looks like, never mind actually testing the solution.

10mm Inconel + Resbond + Stage 8 = win

I'm going to find out if 8mm Inconel is sufficient with a bottom mount 2650 since I already have them from the old MSM setup. It's tight enough getting a wrench on the nuts as-is.

Laur3ns had good luck with some specialty stainless suds from a race shop using Resbond and welding the nuts. A less removable method that does exactly the same thing Stage 8 I guess.

There wasn't a lot of talk about the downpipe connection but Hustler did manage to sheer a standard fastener there. The Nissan 8mm inconel are relatively cheap so I'm just going to use those, rather spend the extra now and not have to worry than have it come apart on a track day.

Nord locks are much cheaper an ebay than from FM. They are also not suitable for the manifold-turbo connection, though it was never explained why (I assume they just don't work well enough?).

Boundary Engineering found some superawesome stainless bolts that would probably work. Metric threads were stupid expensive ($50+ per bolt) so he offered up some SAE equivalents. Never saw if anyone tested it though.

Savington really gets all the credit for figuring out inconel works and it makes me sad he didn't offer 8mm studs when I needed them for the stock turbo.

Anyone know the shelf life of Resbond? I have some in a little bottle that sat for um, a few years.

10mm Inconel is the way to go if you can fit it. 8mm Inconel works but it has to be a perfect install. Resbond is absolutely critical, despite what other vendors claim. Use it on the stud/manifold threads and the stud/nut threads. Stage 8 hardware works, Nordlocks don't. The shelf life of Resbond is 6 months.

The downpipe studs don't stretch or creep, but they do get very brittle, so Inconel there is not a bad idea.

Sixshooter, Full Race does not sell Inconel studs.

Our M10 kit is still the best on the market. The right alloy, the right fasteners, the right threadlocker. We will do an M8 stud as well, but it will be set up for BW EFR, not Garrett.

This is what I use in case anyone is interested: Full-Race T3 & T4 Turbo M10 Stud Hardware Kit - Full-Race.com

https://www.miataturbo.net/attachmen...ine=1424231126

I've never tried an 8mm Inconel, but the 10's have worked perfectly for us for a long time. We had to have them made and at that, it was necessary to grind the threads.

The style of the stud is critical, in my view. The shank (unthreaded center segment) needs to be at least as large as the major diameter of the thread. And of course, sized not to bottom out. Finish taping with a bottoming tap to make sure you aren't fooled when torquing the stud into place.

The holes need equal attention, in that a chamfer of 30 or 45 degrees needs to be established with enough OD to seat the shank.

The stud then, when torqued to about 30 to 35 ft-lbs will seat on the chamfer with great pressure. This does three things;
1. pulls the bolt segment engaged in the manifold into tension that induces compression stresses in the surrounding material of the manifold. This eliminates the possibility of a fatigue failure in the manifold material, as fatigue does not occur in compression.
2. The preload tension in the stud also reduces fatigue failures in the stud as the preload static tensile stress actually reduces the magnitude of any oscillating stress that can come from a variety of sources. Sounds fonky, but real.
3. The grip of the stud in tension on the material between the end of the threads (or thereabouts) and the specific chamfer is very high and this puts an enormous grip on the manifold. A small drop of grease should be applied to the chamfer before torquing up.

corky

Anyone got some leftover <6 mo old Resbond they can mail USPS? :)

No different than hardware store studs and nuts. Nothing special about their kit at all, and certainly not worth mentioning in the same breath as Inconel hardware.

For the back 5 studs iv successfully used the ones from a nissan 300zx. The regular studs would stretch and leave the downpipe loose and start hitting the subframe after about 4 track laps.

Also the stage 8s should fit everything you can grind down the flange a little or even the lock washers so they have a tight fit. I bolted said turbo bolted to the manifold and down pipe and haven't had to tighten them or anything for 2 years. Tons of track time.

Yep. The other turbo vendors in the community sold a wide varlety of "solutions" to this problem based on their own testing. Our testing proved their solutions to be completely inadequate. We then did the testing and R&D to identify the core issue and solve it in the correct way, and we were the first ones to release an Inconel stud kit based on our testing. Everyone else followed suit shortly thereafter.

My recurring problems were solved by inferior A286 10mm studs and Inconel nuts? How did that happen? It's a miracle.
I'll get some folding chairs. We will be accepting worshippers on Sunday morning at 8am.

This is exactly why I only recommend TSE Inconel studs kits. They are more expensive then the competition, but Savington has been the only one to go out stretch studs, swap in his, and run the same lap times without stretching. That to me is worth the extra money.

I really, really like the TSE kit. But why the $155 price tag? Are you turning/milling these up yourself?

Because machining Inconel correctly is not cheap. They are expensive, but you are paying for the best of the best that have been proven to work on track. If the cost of the studs seems expensive, you will shit yourself when the rest of the costs of tracking turbo miata add up.

Bell is $148 and doesn't include Stage 8 hardware. FM is $99 and doesn't include Resbond.

Serious question: What do you think we should charge for bespoke, rolled-thread Inconel studs manufactured in the United States, the best stainless steel locking hardware on the market, and aerospace-grade threadlocker manufactured by a NASA supplier? Our price was $155 because they were very expensive to prototype and test, and our competitors incurred none of those costs, but what price would prompt you to select our product over those competitors?

I think he's just crying about cost like most cheap miata owners cry about every cost of every part under the sun.

I think when you compare to the competition, the choice is pretty clear.

I think some parts by some vendors are overpriced. This is not one of those parts.

Never stated I thought anything was expensive or over-priced, just wanted justification for $155 spent.

And what do you know ^.. There is that justification, straight from the man who built, tested and developed the kit. Exactly what I came to learn. Didn't mean to make it sound like I was undermining you, Savington. I don't know the appropriate cost, for the reasons you stated, which is why I inquired.

Thanks for the prompt reply!

Not to derail here, but I was curious as to peoples thoughts on mounting the turbo with through bolts rather than studs.

I ask as my manifold that has yet to be installed was drilled out to accept a through bolt to mount the turbo rather than having a screw in stud.

Anyone think this is a problem? The tolerances are tight so I'm not super worried about the turbo not perfectly lining up with the outlet of the manifold.

Non-inco will stretch with track use, a bolt will stretch even more than a stud+nut. I actually completely stretched bolts on a street car in a couple months, so I can't even imagine how fast a track car would stretch them.

But I'll let the pro's chime in

I believe the SS studs from BEGI I'll be using in the back of the turbo, are A286.

I wonder if torquing the studs a la Corky Bell would work in place of Resbond?

I give up.

Apparently the A286 yield strength drops off significantly after 1300*F. I guess since I ditched the turbo blanket and upsized to these I haven't exceeded that. I just remembered incorrectly from a couple or three years ago when I bought them. I cannot recall who here originally shared the link with me. I guess I just have Inconel nuts. Try not to stare at them.

This is the worst post I have read in my life.

lol

I'm ordering some soon as SwaintTech ships my exhaust back. Surplus will be bottled and offered for sale here at my cost+shipping. Hopefully soon, they've had it for 3.5 weeks.

I went and ordered some from ebay. You can buy mine when I'm done in ~2 weeks! :)

I guess that means you've tried it and it didn't work, eh?

The next question, is, with Resbond, is it necessary to torque the studs down?

no inconell no care. because absolute garbage waste of time and money anything but inconnel.

To be fair the first set of Inconel studs I used were from BEGI before you had anything on the market.

I used Nordlocks and Resbond on my first set. Never touched them and they never came loose. They were longer studs than yours and I recessed them into my manifold further and countersinking the start of the threads to provide a longer grip lenght and added set screws to keep them from spinning. when I re built my DIY mild steel manifold after 4 years of use I bought a set from you and used the Stage 8 nuts. It’s been more than a year and I haven’t touched them either. Well freeking worth $155.

I havent switched to inconnell on the downpipe yet and I do have the occasional failure. If my downpipe suport to the transmission comes loose the dounpipe flange studs will last about a half a track day as well but they do pretty good if the downpipe support stays put.

Can I do any harm by tack welding the Inconel studs onto the manifold? On the non-face side obviously.

Did you chamfer the entrance of the manifold holes? Did you torque the studs in? What tool did you use?

You're just jealous of my inconel nuts.

https://www.miataturbo.net/attachmen...ine=1424367379

I'm not ignoring this question, but I am choosing not to answer it. My recommendation is that you purchase our kit and install it exactly as the instructions say to. If you want to DIY it, that's fine, but I don't think anyone here will expect me to assist you with that particular endeavor.

I assure you that nobody is jealous of your hardware kit. You got suckered by FR into buying a kit that you assumed to be Inconel at a too-good-to-be-true price. Your studs are nothing special and while they may be adequate for your particular application, they are not a competitor to the kits that actual vendors (FR is not a vendor here, FYI) sell. For the sake of discussion, I'd appreciate it if you would give up on hawking a non-vendor's inferior product on this forum.

Lols

He is an independent 3rd party offering his review of a product he uses first hand on the track with success on rcomp tires and 250rwhp. This product and its use are directly relevant to this thread. While he did originally think they were inconel that information has since been corrected multiple times. It may not be THE BEST solution but it is another data point.

This is not your vendor page so I see nothing wrong with him recommending another product to other members of the forum regardless of their vendor status. Don't get your panties in a bundle over his obvious innuendo about taking his nuts seriously.

....

The holes were countersunk down about 1/2" below the face of the flange. Threads had helicoils in them due to repeated repairs and buggered threads from broken off studs being drilled out and heat barbequing the mild steel threads. My diy manifold allows the thread holes to be extra deep. The first set of studs I got from BEGI were about 1/2" longer than the ones from track speed. They were not bottomed out in the holes as Corky suggests but they were double nutted and torqued in place. Also drilled and tapped small set screw holes in the flange 90 degrees to each stud. Set screws won’t allow studs to turn out.

Second set were from Track speed installed as Andrew said other than using helicoils in the holes before even using it for the first time on the car and they also have been entirely trouble free for over a year.

The material in the helecoils seems to hold up better to the heat for the threads cut in my mild steel flange. McMaster sells High temp nickel helicoils. In 10 and 15mm lengths. Bout the only thing I can say is they seem to work for me with my setup.
McMaster-Carr

C'mon bitches you missed my important question because of all your girlyfightingwords!

If you sold an M8 kit, I'd have bought 'em already.

There is an m8 prototype. EO2K has them. Message Andrew about it.

Too late. I have M8's from FM years ago.

Maybe not? Why NOT torque them a bit, to say, 10-15 ft*lbs?

Try it and post your results. I doubt anybody has welded in inconel studs.

Either way find the right filler.

That's what I'm leaning towards. 30 ft-lbs seems a lot for M8's.

I stock resbond so I dont typically do this but I have done it on manifolds which have had very poor damaged threads, its held up no trouble, TIG'd with 308L wire.

Dann

Thanks Dann I'll try the Resbond again first. I might have to hit you up for a bottle!

Cheers

I tigged one 8 mm FM in Inconel stud to a nut on my MSM turbo with L309 filer. Not structural, just three small tacks.
FM seems to be only real Inconel 8 mm option. They are pricey too considering no resbond and only 8 mm studs. The Trackspeed 10 mm are not bad at $155. If they made 8 mm I would have gone Trackspeed in a heartbeat.

I still want to try the Nissan 8 mm studs on my downpipe to turbo connection.

The points others have brought up about those studs and nuts aside, I've personally had those nord-lock washers fail completely when I tried them.

-Ryan

Nordlocks have failed on my street car.

how did the nordlocks fail?
I've never had them fail. They did not make non Inconel studs work at all, nothing did, but I've never had them fail by themselves.

Inconel studs nordlock and resbond worked for me as did inconel studs stage 8 and resbond. Both with helicoiled stud holes in a mild steel manifold.

I've had the AN hardened high strenght nuts fail miserbly as they shattered into pieces.

2x manifold studs backed out until they hit the manifold. 3x other nuts were loose on the studs.

With inconels, or SS studs?

--Ian

not inconels.

I had inconels ready to go in, but the shop that rebuilt my engine is a piece of shit - didn't install with the thread pitch I told them to install.

Shit, just realized these were manifold to block studs, not turbo to manifold studs. My post above is not relevant to this thread.

If you are seeing failures on the manifold/head hardware, your manifold is warped. The OEM hardware should work on every application (street to full race).

Full Race, you say? :D