ARP Stud Torque Spec

[PMD24]

Can anyone tell me the torque spec for ARP 3/8" header studs (wet), into aluminum heads? Looking through Blueprint's info I haven't come across it yet. On the web I'm finding a generic recommendation of 22 ft lbs.

Thanks,

Pat

[Mike.Bray]

Call or message ARP, they are great at helping.

[PMD24]

Call or message ARP, they are great at helping.

My post previously mentioned (I edited it) that I contacted ARP and they told me to contact the manufacturer! I did get back to them pointing out that they were the manufacturer of the ARP part number I provided. They were very polite and pointed out that their studs could be torqued to 70ft-lbs, but that wouldn't be wise in aluminum and suggested I speak with the head manufacturer. I guess in retrospect, my question was pretty dumb. Also today when I was test fitting the Remflex gaskets it occurred to me that my question may not matter. I know you're a fan of the Remflex. Any guidance on torque or judging the amount of crush?

[BornWestUSA]

AI Overview
For 3/8-inch ARP header studs, tighten the studs themselves into the cylinder head hand-tight (or slightly with an allen key) and torque the nuts to 25-35 ft-lbs. Use anti-seize or thread lubricant on the studs and re-check torque after the first heat cycle (50-500 miles) to prevent leaks.
Stud Installation: Hand-tighten until fully seated in the head; do not torque the stud into the head.
Nut Torque: 25-35 ft-lbs is standard for header applications.
Sequence: Use a center-outward pattern to ensure even clamping.

[Mike.Bray]

My post previously mentioned (I edited it) that I contacted ARP and they told me to contact the manufacturer! I did get back to them pointing out that they were the manufacturer of the ARP part number I provided. They were very polite and pointed out that their studs could be torqued to 70ft-lbs, but that wouldn't be wise in aluminum and suggested I speak with the head manufacturer. I guess in retrospect, my question was pretty dumb. Also today when I was test fitting the Remflex gaskets it occurred to me that my question may not matter. I know you're a fan of the Remflex. Any guidance on torque or judging the amount of crush?

ARP are correct, 70 ft lbs would be applying Hook's Law to the fastener except the soft aluminum won't take that. I have a set of new Remflex gaskets I picked up yesterday for a SBC I'm building and on the package in bold red letters it says:

TORQUE 20 FT LBS

[cv2065]

I installed the stud hand tight with anti-seize. Installed the headers then torqued the nut to 20 ft/lbs. I also used Nord-loc washers instead of the ARP as the ARP washers were backing off. Nord-locs have worked great.

[PMD24]

ARP are correct, 70 ft lbs would be applying Hook's Law to the fastener except the soft aluminum won't take that. I have a set of new Remflex gaskets I picked up yesterday for a SBC I'm building and on the package in bold red letters it says:

TORQUE 20 FT LBS

Thanks Mike, exactly what I needed. I've looked at my packaging numerous times and didn't see that. Will have to look again.

Pat

[PMD24]

I installed the stud hand tight with anti-seize. Installed the headers then torqued the nut to 20 ft/lbs. I also used Nord-loc washers instead of the ARP as the ARP washers were backing off. Nord-locs have worked great.

Thanks. I'm using the ARP lube so no anti-seize with that. I think I recall you mentioning before that the ARP nuts and washers didn't hold for you. Will take a look at the Nord-locs so I have that as a backup. As it turns out, a few of the studs are tough access with a socket, even with a universal without scratching the header. Looking at Stage8s but the price is a big ouch.

[PMD24]

So, relative to the last few posts, here's a question for the experts out there. Is it a bad idea to mix studs and bolts on the headers? It seems to me that torquing studs/bolts that are potentially different materials and/or from different manufacturers would result in different force being applied by the different fasteners.

Thinking about this because my plan was to order some hex head ARP header bolys and use them where I can't access a stud/nut, but use the studs everywhere else. Looks like there may be two on each header. Maybe it's not a factor at all with the Remflex gaskets and only 20ftlb.

Thanks,

Pat

[Mike.Bray]

Thanks Mike, exactly what I needed. I've looked at my packaging numerous times and didn't see that. Will have to look again.

Pat

Yeah, it's very tricky to find.

224665

Sorry, couldn't resist. Don't kill me.

[Mike.Bray]

So, relative to the last few posts, here's a question for the experts out there. Is it a bad idea to mix studs and bolts on the headers? It seems to me that torquing studs/bolts that are potentially different materials and/or from different manufacturers would result in different force being applied by the different fasteners.

Thinking about this because my plan was to order some hex head ARP header bolys and use them where I can't access a stud/nut, but use the studs everywhere else. Looks like there may be two on each header. Maybe it's not a factor at all with the Remflex gaskets and only 20ftlb.

Thanks,

Pat

I'm doing it on my Windsor, I can't get the nuts on in two places on each side. Seems to be okay.

[tnt_motorsports]

So, relative to the last few posts, here's a question for the experts out there. Is it a bad idea to mix studs and bolts on the headers? It seems to me that torquing studs/bolts that are potentially different materials and/or from different manufacturers would result in different force being applied by the different fasteners.

Thinking about this because my plan was to order some hex head ARP header bolys and use them where I can't access a stud/nut, but use the studs everywhere else. Looks like there may be two on each header. Maybe it's not a factor at all with the Remflex gaskets and only 20ftlb.

Thanks,

Pat

Mixing and matching shouldn't be a problem. Keep in mind that the real purpose of torque is clamp load or squeeze. Different materials will deliver the same clamp load but it will require a different torque.

In this instance the joint is a soft joint because of the gasket so stick with the recommendation of 20 ft/lbs

[Bob Cowan]

Over the years, I have learned a thing or two that isn't in the book. For this application I no longer use anti-seize or ARP thread lube. The problem is that within a year or so, one of the nuts or studs will come loose, burn the gasket, and leak at the worst possible time. Then it's an hour or more job to fix that.

Instead, I use hi temp silicone sealant on the threads. It makes a nice lubricant during assembly, and it never works loose.

I also don't use a gasket, only copper based silicone. Fits perfect every time, and also lasts about forever. Cheap, too.

[rich grsc]

100% Bob, EVERY header gasket I have used has eventually blown out. ONLY the copper base silicone has worked for me

[PMD24]

Yeah, it's very tricky to find.

224665

Sorry, couldn't resist. Don't kill me.

Yep, Mike's right. Opposite side of the cardboard from the FAQ's that I've reviewed multiple times, there it was... 20ft lbs... in bold red.

Guess it's time for me to close this one out!

Thanks to everyone that responded.

Pat