Replacing exhaust studs
 

It seems like stainless steel studs have gained popularity in aluminum heads. I was going to replace my studs on the 602 and the stainless steel seem studs are cheaper than steel. Any down sides?

No matter what you use put some never seize type compound on the threads.

Be sure the new studs match the same grade. One of they ways you can tell is by howl much torque they are tightened to. Find the torque and go on the internet and look at a metric bolt chart and see what grade the factory manual torque falls into.

Not all stainless is stainless
 

Agree with Diesel911, anti seize compound is an exhaust systems friend. Also note, there are many grades of metal called stainess, but only the 300 grades 304/316 is truly stainless non magnetic. All 400 series are ferrous and will rust. If in doubt check with a magnet, if it sticks...it will rust.

Match the hardware.

Galvanic corrosion is not your friend. Dissimilar metals + water = corrosion.

Don't mix SST with Carbon Steel.

THESE GUYS ARE 100% RIGHT ABOUT AINT-SEIZE!!


BE ADVISED: There are different grades of anti-seize. One grade is to 900 degrees, the other to 1300 degrees. Use the higher temp version for the exhaust system, it's about $9.00 for a small container that will last you forever.


Suggestion: clean out the tapped holes with a brass rifle brush and high pressure air. Put the stuff on a toothpick to half cover maybe 4 of the threads. Screw it in slowly so that it gets on the threads, unsrew it and check to see how far it went. Do this a couple times for complete coverage.
After torqueing the studs in place with two nuts on the top of the stud, remove the nuts and go to the next one.


I would spend the money to use either brass or stainless steel nuts on the exhaust system, you will thank me later, I did this on my 57 Citroen and never regretted it.

All steels are ferrous, i.e., iron based, including all stainless steels.
This is the first paragraph of a Wikipedia article on Stainless steels:

Stainless steel is a group of iron-based alloys that contain a minimum of approximately 11% chromium, a composition that prevents the iron from rusting and also provides heat-resistant properties. Different types of stainless steel include the elements carbon (from 0.03% to greater than 1.00%), nitrogen, aluminium, silicon, sulfur, titanium, nickel, copper, selenium, niobium, and molybdenum. Specific types of stainless steel are often designated by a three-digit number, e.g., 304 stainless.
Stainless steel's resistance to rusting results from the presence of chromium in the alloy, which forms a passive film that protects the underlying material from corrosion attack, and can self-heal in the presence of oxygen. Corrosion resistance can be increased further, by:

• increasing the chromium content to levels above 11%;
• addition of 8% or higher amounts of nickel; and
• addition of molybdenum (which also improves resistance to "pitting corrosion").

The matter of a grade of stainless steel being magnetic or non-magnetic is not related to corrosion resistance; it is a separate property related to grain structure (ferritic, austenitic, or martensitic).

This evil energy stud kit seems to be 304 SS comes with SS nuts and thermal expansion washers.

https://www.amazon.ca/EVIL-ENERGY-Exhaust-Intake-Manifold/dp/B07VC7NNXR

It is generally inadvisable to use a nut of the same grade of stainless steel as the stud or bolt. Galling and seizing is the usual result. Use a 400 series nut on a 300 series stud, or better, use the OEM copper plated nuts.