DeerHunter

Here's the thing: Broken studs can potentially leave you stranded on the side of the road. They are not particularly easy to change out either, and if one has snapped of flush with the manifold, you have tripled your fix-it time. Given all that, it seems to me to be a false economy to save a few bucks on a do-it-yourself kit.

If you track your car, stock studs will almost certainly fail. If you drive on the street hard (and who with a turbo doesn't), they might. If you street drive with the occasional autocross or HPDE thrown in, they will probably fail (mine did, right before a scheduled 10-day road trip).

I think what people are trying to say is that you are trying to reinvent the wheel. A lot of people did the leg work on this already so that you don't have to. Buy the proven kit and avoid later heartache. YMMV.

hornetball

iTrader: (4)

Here's the thing about engineering, you need to adapt the solution to the problem. The problem is heat. But the degree of the problem varies. The heat generated by track-driven 250RWHP+ is an order of magnitude different from the heat generated by street-driven ~200RWHP (which is what you'll likely get with the Greddy and an intercooler).

From personal experience street-driving a Greddy installation for >10,000 miles, safety-wired mild steel bolts (grade 8.8 or better) are a reliable solution. I bolted mine on in April 2011 and have never touched them. No leaks ever. Cost was minimal.

You do have to learn how to safety wire though.

If I were regularly tracking this car, then I would do a different solution because I would be facing a different problem.

Just sayin'

nperkins

Thank you for your reply. I understand what people are saying, and I understand this is was over a very long period of time... I just didn't understand the $155 cost for 4 studs, fasteners, and some threadlocker... That's why I started looking around to learn more, and found the full race studs...

Sounds like you have a similar setup to me. I don't plan on tracking the car much if any... And I was actually going to drill & safety wire before I saw the Stage8 fasteners, then found out my friend had them in stock at his shop.

triple88a

iTrader: (2)

I didn't either, so i looked it up how inconel studs are made, machined and finished. In this closed community our reputable vendors aren't full of ----.

hustler

iTrader: (6)

hornetball

iTrader: (4)

As long as we're getting into the science, it's worth looking at the thermal expansion properties of various metals (in [#] x 10^-6/°C). The following numbers are at room temperature (note that thermal expansion coefficients vary with temperature -- the following just illustrates what might be good vs. bad choices when encountering temperature creep):

1. Cast Iron: 11.8 x 10^-6/°C
2. Steel: between 11 and 13 (depends upon formulation, Inconel falls in this range)
3. Stainless Steel: 17.3
4. Brass: 19

The objective with a cast iron or tubular steel manifold that is going to see a lot of heat for long durations is to match these properties to preserve the mechanical relationships. As you can see, with a cast iron manifold, you can't do much better than a steel fastener. Also, you can't do much worse (at least out of this list) than stainless or brass.

Stainless and brass are mainly used in these applications where corrosion is the primary concern and you don't expect a lot of thermal creep. Perfect for my Plymouth Sport Fury with a 440. Not so great with a turbo. I'm surprised that you've been able to use them so successfully in other turbo applications.

Steel works pretty well, but does give up strength as things heat up.

Inconel is perfect here. Expansion coefficient match + high temperature strength. Profit. When and if I move on from my Greddy, I'll be calling Sav.

nperkins

I'm not saying they are full of anything... Just poising the question... I read up on inconel as well... Which is why i'm wondering about why inconel on the stud vs the nut..

Is this what you were trying to post?

Savington

iTrader: (31)

So you understand that it took us a long time to diagnose, develop, and test a solution to this issue, but you don't understand the associated costs?

Our studs are specifically made for our application by a US fastener company that specializes specifically in wacky custom high-grade fasteners like this. They're sized specifically to fit in the Miata application - 2mm shorter or 2mm longer and they wouldn't. They are also roll-threaded, which improves thread strength (especially with Inconel). Our kit is the ONLY kit that includes Resbond, and despite other companies insisting that it's not necessary, we know better (and our testing proves it).

You cannot purchase studs from our supplier because our supplier won't even talk to you until they have a four-digit check in their hands. You could order a similar stud with cut threads from another supplier (the one we worked with for our prototypes), but their asking price when we developed them was ~$75/stud, and I suspect it's gone up from there. That's just the cost of the studs - that's not including the money we spent on testing and vetting.

The FullRace page says that T25 turbos need M8 studs - that's obviously false as dozens of our customers have proven. They also never specifically state that their studs are Inconel - they use the A286 designation, but I can buy A286 Stainless Steel as well, so that means nothing.

If you're really a stickler for price, I'm not going to stop you from buying elsewhere, but a lot of people have bought from us because we're the ones who took the time to develop a solution that has been proven time and time again to work.

Savington

iTrader: (31)

I spent 2 days in a Spec Miata at Watkins Glen last week with my dad, and on Saturday afternoon I spent 4 or 5 laps chasing down a black Miata with gold stripes who was maybe ~1s a lap slower. It looked very similar to an SM from the driver's seat, so when I finally got by him, I didn't think much of it.

He came over to our paddock after the session, and the first thing I noticed was the intercooler in the mouth. He popped the hood and wandered off, and I glanced at the engine bay, which had an old FMII kit inside. I was going to ask the owner what he was using for studs, since he was able to do full sessions at SM pace, but I didn't need to - the studs in his manifold had "TSE" stamped on the end.

DeerHunter

My first turbo kit was a (modified) Greddy. It took a little more than a year, but I had a broken stud with that one too. A sample size of one doesn't mean anything, so one of our results is atypical. If I knew then what I know now (and Inconel was an available option), I would have jumped all over either TSE or FM's Inconel offerings. Did I mention that changing the studs is a royal pain?

Savington

iTrader: (31)

Not only is it a huge PITA, but if you use a crappy stud and mess up M10 threads in the manifold, you run the risk of turning it into a doorstop. All the Resbond in the world won't help you if the threads in the manifold are so sloppy that the stud never tightens up.

hustler

iTrader: (6)

My buddy is taking his manifold to the EDM shop to remove the broken studs since there is some old-stud counter-sunk into the manifold, lol. I think ECM stud blow-out is not cheap.

curly

iTrader: (25)

Fair enough, all I saw earlier was the $175 shipped.

We're being persistent because we've been through this. If you've read this entire thread, you'll realize we've been through hardened, brass, SS, 8mm, 10mm, and everything in between for studs. We've tried safety wire, locking washers of all verities, stage 8, nordlock, and everything in between for securing the nuts. None of it worked consistently on hard core track machines until TSE went through extensively testing, R&D, multiple material selections, and finally rolled out their complete, track tested product. Is it priced steep for 4 bolts and 4 nuts? Probably, even with the exotic material, but you're paying for their extensive testing.

You've come in here, suggesting $20 hardware, haven't used anyone but yourself for testing, and you haven't done any track testing, much less fast track testing.

Although we appreciate you arguing your point and reminding us of TSE's commitment to quality products, do NOT continue this line of argument.

240_to_miata

iTrader: (2)

Yeah its a pretty pointless argument. TSE has found a well engineered solution. I pulled my manifold off the turbo today and after my track day (at 175 rwhp on a t25) every single bolt on the DP, elbow, and manifold was loose. I already learned the hard way NOT to use SS hardware because of the expansion rate. This was all mild steel & oem sizes. I even had M8 stage8 hardware on the mani to turbo connection.

Oh and FYI my stock OEM studs were so weak after the track day that I snapped one off flush. Good thing I was doing all of this to upgrade to TSE while I rebuild the turbo.

Just another prime candidate for the TSE upgrade

MartinezA92

iTrader: (4)

I can vouch for this.

czubaka

iTrader: (3)

Has anyone tried welding the turbo to the manifold? No stud creep with that solution.

JUST KIDDING! 1 warning for czubaka...

shuiend

iTrader: (24)

Yes it has been done. If you read the whole thread you can see the pictures.

k24madness

iTrader: (6)

I have been on both sides of solving such problems. I will gladly pay the retail price over the developers cost of such things.

sixshooter

iTrader: (12)

Cotronics has a minimum order of $75. I looked to them for heat blanketing material once and ended up elsewhere because of the minimum order problem.

So...

hustler

iTrader: (6)

Spoolin2bars did I believe, and it works.