Recommendations On Header Bolts?

[BPBP440]

I am surprised at the huge range in prices for header bolt sets. I am putting Doug Thorley headers on my 440 (906 heads) in a 70 B-Body.

What bolts do you all prefer and why?

Thanks-

 

[Aarons Air]

I used studs & nut instead of bolts. If you ever have to drop a header for starter replacement, or anything else, header bolts can be a pita !

 

[Wietse]

I just installed my new TTI headers using studs. (906 heads too)
Reason for using studs is to have some more insurance against cooling water leaks from the stud holes.
The shoulder of the stud tightens up against the head which should provide a good seal.
And i used Permatex on the stud threads when installing them.
I measured what total length is required to keep them as short as possible to ease installation in the car.
The longer they are the higher the engine needs to be raised to get the header installed/removed.

 

[dvw]

ARP stainless. They never rust. studs are nice, IF. Some headers have bends that are to close for studs.
Doug

 

[Wietse]

Yeah, on my old headers i had to get the nut started before pushing the header against the head otherwise i could not get the nut on.
From that experience i cut them as short as possible this time to avoid that, which worked out well.

 

[RJRENTON]

ARP stainless. They never rust. studs are nice, IF. Some headers have bends that are to close for studs.
Doug

Sometimes stainless steel studs can become gaulled, especially if using a stainless steel nut, and having been in hot service. And it also depends on the alloy. 304 stainless is most common but 316 is more corrosion resistant than 304, although 309 and 310 have better hot tensile strength and offer good tensile strength. Consider using a nickel based anti-seize compound on the external threaded portions. I've used Everdure hardware on all exhaust components. Everdure is a copper, silicon, manganese alloy material that is corrosion resistant yet provides high tensile strength. FastenAll or McMaster-Carr is a source. Just a thought....
BOB RENTON

 

[kiwigtx]

I went with Studs and External Star washers on the headers for my 408.

The trick is to have clean flat surfaces, and tighten several times...checking all nuts are even.

 

[Wietse]

True, ss bolt and nut can go rougue on you.
SS studs with brass nuts maybe?
I think any anti-seize compound is not going to survive the heat overtime and will burn up, even the "heat resistant" ones go dry over time.

Guess this is not for sale for fasteners, but there is a certain stainless alloy used as wel for fabricating header, being in the 400's. Something like 430 or so and apparantly this is more heat resistant and by far does not expand so much as 304 or 316.

 

[493 Mike]

Iv'e put headers on lots of cars/trucks over the last 50 years and I always used what ever the manufacturer sent in the box. Always seemed to work.
Mike

 

[PurpleBeeper]

For bolts, the cheapest ones that have 7/16" or maybe 3/8" heads to give you more wrench clearance. Having said that....
1. Studs are best to not have leaks (as mentioned above)
2. Studs also have the worst clearance putting headers on.
3. Also as mentioned, some header bends (e.g. right angles right at the flange) can limit what will physically fit.
4. If you have aluminum heads, I'd strongly recommend trying to use studs so you don't strip the female threads in the heads running bolts in/out. With iron heads, it's less important.

Everyone likes to say what they run personally, so I will too.... I run studs that I've shortened about 1/4" and header bolts on the ends of the heads...the holes that go into the cooling jackets, and yes I have leaking issues with those. They're iron heads, fyi. At one point, I ran a set of headers that had a really bad clearance and/or wrench access issue. Otherwise, I would be running all studs.

 

[RJRENTON]

True, ss bolt and nut can go rougue on you.
SS studs with brass nuts maybe?
I think any anti-seize compound is not going to survive the heat overtime and will burn up, even the "heat resistant" ones go dry over time.

Guess this is not for sale for fasteners, but there is a certain stainless alloy used as wel for fabricating header, being in the 400's. Something like 430 or so and apparantly this is more heat resistant and by far does not expand so much as 304 or 316.

FYI...The permatex nickel anti seize is good to approximately 2400°F. The copper based anti seize is good for approximately 1800°F and the good old graphite (carbon) based product is good for approximately 1100°F. After the carrier burns away the nickel, copper or graphite base will remain viable. The 300 series stainless steel alloys are considered austinetic, this includes the high nickel alloy materials including Inconel 800H,800HT, 800AT, the Incoloy 600, 601, 625 and Carpenter 20 alloy. The 400 series stainless steel alloys are considered ferritic, like the 430 you mentioned are basically iron and chrome alloys (no nickel) and are corrosion resistant but can be brittle. 430-grade Stainless-Steel offers superior corrosion resistance when compared to chrome-plated steel. However, due to there being less chromium, and slightly more carbon in the metal, 430 Stainless-Steel is less resistant to corrosion than 304 Stainless-Steel.
The expansion ratio, is called coefficient of linear expansion and is alloy, diameter and length dependant.
Just thought you might like to know...
BOB RENTON

 

[BPBP440]

Wow, that is a lot of options. How about locking versus non-locking?

 

[snakeoil24]

Stay away from anything stainless! The loosen up and leak. Sure they don't rust but are a headache for constant tightening. Get yourself copper gaskets and black small head 12 point bolts, drill them for safety wire and be done with the problem. Also remember anti seize on threads.

 

[mopar 3 B]

Stay away from anything stainless! The loosen up and leak. Sure they don't rust but are a headache for constant tightening. Get yourself copper gaskets and black small head 12 point bolts, drill them for safety wire and be done with the problem. Also remember anti seize on threads.

How do you safety wire header bolts? Guess you could the four internals.

 

[snakeoil24]

Cross drill the bolt heads

 

[snakeoil24]

Allen heads are easier to cross drill

 

[HEMI-ITIS]

My headers are 5 pieces and easy to do from-under
I prefer the multi piece myself.

 

[khryslerkid]

I just use a stud at both ends with brass nuts.

Makes it much easier for removal and installing.

 

[ChargerST]

Try to find a set of Mr Gasket 3415 header studs. They are discontinued but can be found on ebay. The cool thing about these is that one end is smaller and the smaller nuts give additional clearance.

 

[dvw]

I've had zero problems with stainless header bolts. Running them in both aluminum and iron heads. They don't come loose. My Challenger hasn't has a header bolt tightened since it was build 17 years ago, except when the headers were recoated. Heck the headers have been on/off my racecar numerous times in the last 8 years. The threads are still fine. The heads were well used when I bought them as well. Agreed if you have room for studs it makes installation easier. As far as stainless nuts galling. My heads are studded for the valve covers. I use stainless nuts to retain them. The covers come off roughly every 20 passes for lash checks. The car has over 630 passes. Never an issue.
Doug