Stainless steel header hardware - cons?

[vacuum 6]

I've done some research but haven't seen info supporting reasons not to use SS on exhaust manifold (headers). Can you guys please provide some insight.

I'm looking to install 316 SS studs and nuts in Champion aluminum heads. 316 is good up to 2000° F.

Composition/Properties - SSINA

www.ssina.com

 

[TexasT]

Stainless can gaul when fastening into aluminum. Never seize would be on em if I was using them, but I'm not sure I'd be using stainless fasteners. I guess of you never have to get em back out you'd be good.

 

[Jerryl]

. . . . . I guess of you never have to get em back out you'd be good.

LOL.

 

[Turbo6inKY]

It can gall in cast iron, too. But with aluminum it's particularly bad. You will get problems with galvanic corrosion that doesn't happen with regular steel fasteners.

Use plenty of anti-seize, and put it on your schedule to break them loose and re-tighten them at a reasonable interval.

And "good" to 2000 isn't quit accurate. They won't melt, but they will release their clamp load well below 2000 degrees, at which point the gasket will fail. But the header flange typically doesn't ever get that hot. It's mated to a water-cooled head, after all.

 

[Ttype6]

I'm looking to install 316 SS studs and nuts in Champion aluminum heads.

I don't like studs because you have to move the headers a significant distance from the exhaust port before you can remove them. That would be problematic on the drivers side.
I love these things. You don't wrench them down like you would with non locking bolts and everything tightens when it all warms up. They won't come loose and they have always come off,for me,just like they were put on the day before. The biggest problem with aluminum threads is when they are hot.

 

[vacuum 6]

On my headers there's plenty of hole clearance. Aluminum heads and studs, less chance of thread stripping.

I've used SS nuts for turbo to header attachment and the nuts always came loose. Good info thanks guys.

 

[Turbo6inKY]

On my headers there's plenty of hole clearance. Aluminum heads and studs, less chance of thread stripping.

I've used SS nuts for turbo to header attachment and the nuts always came loose. Good info thanks guys.

I had to replace my turbo-to-header studs with Inconel to get them to stop releasing.

 

[vacuum 6]

I had to replace my turbo-to-header studs with Inconel to get them to stop releasing.

Supplier?

 

[NY Twin Turbo]

I use ARP stainless studs (course to fine thread) in my aluminum Champion heads with anti-seize applied. But I don't use the 12 point ARP nuts. Instead, I use standard store bought fine thread stainless steel hex head nuts with split lock washers.

Never had any problems. I have had the headers and studs out about 4 times in 13 years or so. And my headers never come loose and they never leak at the flanges. I use copper embossed gaskets ported open to the very edge of the embossment.

 

[Turbo6inKY]

Supplier?

Trackspeed:

Trackspeed Inconel Stud Kit

Don't allow the failure of an inadequate $2 stud to ruin your next track day. Eliminate turbocharger fastener failure with Trackspeed Engineering's Inconel stud kit. M8x1.25 and M10x1.50 applications are available for Garrett and Mazdaspeed turbochargers. We also have a specific M8x1.25 stud...

www.trackspeedengineering.com

They're a Turbo Miata shop, but they sell a Inconel stud kit for Garret housings. The M10x1.5 kit fits the three bolt garret housing most of us have.

Prior to putting this in, I'd burn through the turbo flange gasket at every event. After installing this, I have four track weekends on it and it's still sealed. And the Inconel doesn't corrode or gall, so pop the locks off the nuts and it comes right apart.

 

[captndave737]

Galvanic corrosion is a real problem. I'd use plenty of anti seize and check them often.

 

[Ttype6]

Prior to putting this in, I'd burn through the turbo flange gasket at every event.

Never use a gasket and the fasteners will never come loose no matter what kind they are.

 

[Turbo6inKY]

Never use a gasket and the fasteners will never come loose no matter what kind they are.

Actually not true!
Perhaps in normal usage, but 6000' of WOT per lap for 20 minutes and steel fasteners are begging for mercy.

 

[~JM~]

Actually not true!
Perhaps in normal usage, but 6000' of WOT per lap for 20 minutes and steel fasteners are begging for mercy.

Have you tested REMFLEX gaskets?

Remflex exhaust gaskets (header - manifold - gasket) - OnLine Catalog

I have a set on V-8 headers & collectors. Work great in that application, as long as you can install them without breaking them. Do not allow them to bend.

 

[Turbo6inKY]

Have you tested REMFLEX gaskets?

Remflex exhaust gaskets (header - manifold - gasket) - OnLine Catalog

I have a set on V-8 headers & collectors. Work great in that application, as long as you can install them without breaking them. Do not allow them to bend.

Yup, I have remflex on the headers and the turbo flange and downpipe flange locations.

Running without gaskets is only really possible if your flange surfaces are smooth. My housing has been beat up a bit and has some pitting. It'd have to disassemble the turbo and have those surfaces machined. The Remflex seals it all right up as it sits...

...as long as you don't use steel fasteners. They'll eventually release and the gasket will burn through:

This was with steel studs and lock nuts. The locknuts held. The studs backed out of the housing.

But my use case is extreme. most people won't have this problem, or it'll take years to happen.

 

[turbo nasty]

Turbo to header run a SCE copper gasket be sure flages are flat and a smear of copper rtv ...send it

 

[earlbrown]

Been running plain ole course thread stainless bolts on my headers and crossover for many many years. (only place I use studs is the 3 on the DS that hold the brackets and dipstick)

My THDP came with stainless bolts and they never came loose.


Of all my header bolt kits I've sold I've never heard of one person having a problem. Granted I send out a ketchup pack of anti-seeze, but I have no idea if they actually use it.

On aluminum heads, they really should have SS heli-coils install in all the holes. It's a hellovalot easier to fix a problem for good before it becomes a problem.
.....and if my header bolts every get 2000F, my engine have already fully melted down.

 

[NY Twin Turbo]

Been running plain ole course thread stainless bolts on my headers and crossover for many many years. (only place I use studs is the 3 on the DS that hold the brackets and dipstick)

My THDP came with stainless bolts and they never came loose.


Of all my header bolt kits I've sold I've never heard of one person having a problem. Granted I send out a ketchup pack of anti-seeze, but I have no idea if they actually use it.

On aluminum heads, they really should have SS heli-coils install in all the holes. It's a hellovalot easier to fix a problem for good before it becomes a problem.
.....and if my header bolts every get 2000F, my engine have already fully melted down.

This what I’m saying!

Never thought this was so complicated.

 

[Turbo6inKY]

This what I’m saying!

Never thought this was so complicated.

It shouldn't be complicated. I'm an outlier. Plus work has been boring lately.

One lap of NCM has three 1500'+ WOT sections. That's three drag runs per lap, with just 15-20 seconds of part throttle in between each WOT blast. For twenty minutes. Steel hardware would last three sessions of that, and on the fourth would release and blow the gasket.

So steel is going to work for almost everybody here if they're just toodling around. They will eventually cycle out, but it'll take years. I had the same turbo flange studs and nuts on mine from 1987 until I replaced the turbocharger in 2012. That set lasted until my second event last year. Then I went through a set every event until I put the Inconel in it.

 

[~JM~]

...I'm an outlier....

There are a few on this forum. Mostly chasing 1/4 mile times & H.P. numbers. Those who are performing in extreme case scenarios have the most interesting posts.