JasonC SBB

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?

bbundy

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.

Miater

Is drilling and safety wire worth the effort?

shuiend

iTrader: (24)

Drilling and safety wiring what exactly.

sixshooter

iTrader: (12)

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

midpack

iTrader: (3)

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.

JasonC SBB

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

Savington

iTrader: (31)

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.

sixshooter

iTrader: (12)

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

Corky Bell

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

JasonC SBB

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

Savington

iTrader: (31)

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.

Twibs415

iTrader: (8)

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.

Savington

iTrader: (31)

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.

sixshooter

iTrader: (12)

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.

shuiend

iTrader: (24)

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.

NBoost

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

shuiend

iTrader: (24)

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 **** yourself when the rest of the costs of tracking turbo miata add up.

Savington

iTrader: (31)

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?

18psi

iTrader: (76)

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.