Installing Cometic HG and ARP studs

[iTurbo]

I plan to install the head on a TIII motor I'm building this weekend. The shortblock is on an engine stand, and I have the stock thickness Cometic MLS gasket and a set of ARP head studs ready to install.

I've been searching a few threads on this subject, but I still have a few questions/concerns...

1. When installing a Cometic HG, should I use copper gasket spray? If so, should I do both sides of the gasket and how thick should the coat be? The head and block have not been resurfaced to the RA spec provided by Cometic. The head was resurfaced when it was rebuilt by Lone Wolf several years ago. I was hoping to just clean the daylights out of everything and run it....There is not a machine shop local to me that could resurface to that spec anyway..

2. I had imagined that I would install the head studs first, then lower the head onto the block...But looking at recent threads, this sounds like it's not going to be practical. From the sounds of it, I should install the head and gasket, then use a stock headbolt to hold the head in place on the dowels, THEN install the studs with the head in place?

3. I've heard of people using Loctite (red?) to secure the studs into the block. Is there a benefit to this? Advisable or no?

4. I've read that the studs should NOT be bottomed out in the block threads. How many turns should I back the studs out after they bottom? I hope it is not difficult to keep the studs from turning when applying torque to the nuts. I suppose using Loctite would help in this respect.

5. I've read the torque specs for the nuts should be anywhere from 80-100 ft/lbs. I suppose I'll just go with 85 ft/lbs initially, but how soon should I check/retorque? Probably after a few heat cycles? Do I have to retorque periodically, or are they good to go after retorquing once or twice?

[bgbmxer]

I just used a little bit of the lube that is provided with the studs I would never use loctite in that application honestly. I chased the threads and then turned them in by hand then put the nuts on and torqed in 3 sequences I believe.

[wheming]

Thanks for asking those thorough questions iTurbo. I'm a few weeks away from installing a Cometic HG and ARP studs in Mini and you touched on things I hadn't realized yet.
I asked about the copper spray before on the Cometic and the replies were mixed. But when I did, I decided to spray thinly but evenly. I figured since I didn't have the recommended surface finish it was probably a good idea.

Btw, when you said "stock thickness" which one is that? The 0.066"? I think that is basically stock thickness on the MP gasket.

[glhs727]

I plan to install the head on a TIII motor I'm building this weekend. The shortblock is on an engine stand, and I have the stock thickness Cometic MLS gasket and a set of ARP head studs ready to install.

I've been searching a few threads on this subject, but I still have a few questions/concerns...

1. When installing a Cometic HG, should I use copper gasket spray? If so, should I do both sides of the gasket and how thick should the coat be? The head and block have not been resurfaced to the RA spec provided by Cometic. The head was resurfaced when it was rebuilt by Lone Wolf several years ago. I was hoping to just clean the daylights out of everything and run it....There is not a machine shop local to me that could resurface to that spec anyway..

2. I had imagined that I would install the head studs first, then lower the head onto the block...But looking at recent threads, this sounds like it's not going to be practical. From the sounds of it, I should install the head and gasket, then use a stock headbolt to hold the head in place on the dowels, THEN install the studs with the head in place?

3. I've heard of people using Loctite (red?) to secure the studs into the block. Is there a benefit to this? Advisable or no?

4. I've read that the studs should NOT be bottomed out in the block threads. How many turns should I back the studs out after they bottom? I hope it is not difficult to keep the studs from turning when applying torque to the nuts. I suppose using Loctite would help in this respect.

5. I've read the torque specs for the nuts should be anywhere from 80-100 ft/lbs. I suppose I'll just go with 85 ft/lbs initially, but how soon should I check/retorque? Probably after a few heat cycles? Do I have to retorque periodically, or are they good to go after retorquing once or twice?

1. yes, use copper spary, and do a quick couple of coats, you don't need a lot, let it tack up a bit before install.
2. the head on the dowels,hold in place, then thread in the studs. There is a reason why arp put the allen head on top. Trying to wrestle a 50 pd head over 10 6 inch studs is crazy!
3. Use the arp moly lube and NO LOCTITE
4. thread the studs to the bottom, but stop there. The clamping force on studs vs bolts is different so it doesn't have the be totally bottomed out, but you want to make sure all the bottom threads are thoroughly engaged.
5. torque to 85, but you can take it to 90-95.... recheck after it's been ran, then sat overnight so it's totally cold... you could recheck after 500 miles, but probably be OK

[turbovanman²]

These studs aren't made for our engines, so tighten down hand tight and I back off 2 turns, then when installing the nuts, I hold the stud from turning as it will, then after you snug the nut down, then torque, good to go.

Wheming, the 8 valve studs are designed for that motor so just snug down finger tight and your good.

EDIT, corrected myself, AREN'T made, lol.

[iTurbo]

Thanks for the fast response all!

...so I should spray both sides of the HG correct?

[glhs727]

Thanks for the fast response all!

...so I should spray both sides of the HG correct?

yes, both sides...

[GLHNSLHT2]

I bottom the studs then back off 1/2 turn so thy're just not sitting on the bottom. On my 8v I snug them all up then go 45-65-85-85. I then fire up the car and let it idle till the fan cycles once and shut off. Let it cool completely then retorque. I didn't do this the 1st time. Thought I'd drive it home gently and come back and retorque it. Yea geting on the freeway the head lifted and sprayed coolant out the side. Studs had about 60-65ft-lbs on them when I got to my shop and checked it. So now it's always a heat cycle and retorque. Haven't had a problem since doing that. This is using stock MP gaskets.

[Lotashelbys]

These studs aren't made for our engines, so tighten down hand tight and I back off 2 turns, then when installing the nuts, I hold the stud from turning as it will, then after you snug the nut down, then torque, good to go.



I bet I have installed ARPs in 50 TIIIs now and I have ran them down to hand tight everytime and never had to back them off 2 turns. Even with a head that is still close to 5.020 for thinkness.

[turbovanman²]

I bet I have installed ARPs in 50 TIIIs now and I have ran them down to hand tight everytime and never had to back them off 2 turns. Even with a head that is still close to 5.020 for thinkness.

Your simply lucky, I've found some bottom out in the block as they are designed for a Honda. I almost cracked my block, scared the shitt out of me, and yes, I chase and clean out my holes. If you checked, I'd bet yours are close or even touching. Even backing out 2 turns, they still have plenty of meat and they do turn when torquing up.

[iTurbo]

I will make sure to get the block's threads uber clean, but do I use the ARP moly lube on both ends of the stud? And yes, I will make sure to put a bit on the underside of the nuts.

Also, I see these studs have an internal hex in the top of them. This should help me from getting the studs too tight in the block (?) but with a socket and torque wrench in place, I won't be able to hold them that way. I hope the studs don't turn farther in when applying final torque. I suppose I could mark them with a Sharpie or something to verify they haven't moved after I'm done.

Thanks again for all the help.

[zin]

Only lube the parts subject to desired movement, ie the top part of the studs, nuts and top of the washers, where the nut will make contact.

Once you get some tension on the stud, they shouldn't want to move much, even less as more tension is pulled, it is a good idea to mark them so you know if and how much they've moved. If you really want to know, you can measure their heights before and after, but if you've backed them off the bottom a turn or so I doubt you'd have an issue.

Mike

[Directconnection]

Your simply lucky, I've found some bottom out in the block as they are designed for a Honda. I almost cracked my block, scared the shitt out of me, and yes, I chase and clean out my holes. If you checked, I'd bet yours are close or even touching. Even backing out 2 turns, they still have plenty of meat and they do turn when torquing up.

Simon, I am not understanding what you're saying. They all bottom out. And how do you know you "almost cracked a block" as either you did, or you didn't. And why 2 full turns? Why not 1? Or just hand tight like Jackson does. What is the reasoning for 2 turns again?

[zin]

I ASSUME, Simon is trying to ensure the studs don't bottom, and potentially overstress the block when torquing the head ... just being overly cautious. Please correct me if I'm off base here.

Mike

[A.J.]

I pretty much do what Cindy said except after the stud bottoms out I back it off about a 1/2 turn. If it turns back in when I install the nuts I don't worry about it. I just want to make sure they're in all the way, just not tight in the block. One other thing, when I use head studs or bolts for that matter, I lube up the washers and the bottom face of the nuts with the ARP moly lube so not only is there no friction on the threads when tightening, there is no friction between the nut, washer, and head so you get a true even torque.

[turbovanman²]

Simon, I am not understanding what you're saying. They all bottom out. And how do you know you "almost cracked a block" as either you did, or you didn't. And why 2 full turns? Why not 1? Or just hand tight like Jackson does. What is the reasoning for 2 turns again?

The studs for the TIII are for a Honda, so the shoulder of the stud will not touch the block, so if you have a good clean hole, the stud can bottom out. When I first used these, I went to tighten them up and a few felt spongy, you know when they won't tighten properly, thought I cracked the block, scared the crap out of me, so I took the head off and sure enough, you can plainly see how the shoulder doesn't touch the block, I so figured 2 turns is more than enough to solve that. Never had an issue so its worked for me. My 2 cents.

[wheming]

Shouldn't the shoulders on the studs make contact with the block?
Should the studs be trimmed a bit?

I guess it matters little if you are fine with simply backing them out a bit.

[zin]

No, the shoulder shouldn't make contact; with a stud you're going for pure stretch, no twist, which contact of an unthreaded section could induce when torquing the nut.

While this isn't going to be as critical as bottoming out the stud and then torquing, which could break the block, it is good practice.

Mike

[5DIGITS]

Only lube the parts subject to desired movement, ie the top part of the studs, nuts and top of the washers, where the nut will make contact.
Once you get some tension on the stud, they shouldn't want to move much, even less as more tension is pulled, it is a good idea to mark them so you know if and how much they've moved. If you really want to know, you can measure their heights before and after, but if you've backed them off the bottom a turn or so I doubt you'd have an issue. Mike

Mike has brought up a critical point to this process.
The stud threads that are inserted in the block should not have any lube applied.
Additionally, the bottom of the washers and their mating surface on the block should be clean and dry during installation.
Only the top of the washers and threads that mate with the nut should receive ARP lube.
If the washer rotates during the torquing process, the installation torque value will not be accurate.
This is why the original head bolt washers had 'spurs' on the underside, to lock them to the head and inhibit rotation while torquing.
Note: Scuffing the washer on one side with coarse sandpaper will also reduce the chance of washer rotation, when torquing.

Enjoy

[turbovanman²]

Shouldn't the shoulders on the studs make contact with the block?
Should the studs be trimmed a bit?

I guess it matters little if you are fine with simply backing them out a bit.

This only applies to the TIII. 8 valve are the correct application so you don't need to back them off.

[iTurbo]

I got the head installed with the Cometic gasket and ARP studs today. I decided to install the studs finger tight, then back off just a tiny bit. I only used the ARP moly lube on the upper threads, bottoms of the nuts, and tops of the washers. I used Permatex copper gasket spray on both sides of the gasket. Everything went great, thanks for the help all!

44964

[trannybuster]

^^Awesome...

[iTurbo]

So I'm wondering about how I'm going to go about engine break-in..

Do I warm up the engine until the radiator fan cycles on/off, let cool overnight, and retorque the head studs......or do I warm up the engine and hit the highway in order to seat the new piston rings and THEN bring the car back to the shop, let it cool, and retorque the head studs? Chicken or the egg?

[GLHNSLHT2]

Guess in my original post I didn't think about it being a cometic gasket. Do you need to retorque a cometic? I would lean towards maybe not needed too since there isn't the compression of a fiber gasket. Thoughts??

[zin]

Re-torque after a heat cycle, then break-in. It would truly suck to have the gasket let go while breaking in a new engine.

The break-in shouldn't be too harsh, but the short time it will take to heat cycle it shouldn't take any toll on the engine, and you'll have peace of mind that the gasket is ok.

I'm a bit "particular", so I'd check the torque a while later too, just cause I'm paranoid like that.

Mike

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Re-torque after a heat cycle, then break-in. It would truly suck to have the gasket let go while breaking in a new engine.

The break-in shouldn't be too harsh, but the short time it will take to heat cycle it shouldn't take any toll on the engine, and you'll have peace of mind that the gasket is ok.

I'm a bit "particular", so I'd check the torque a while later too, just cause I'm paranoid like that.

Mike

[86Shelby]

I did it the opposite of Mike. I started it, kept the RPMs around 2k to get it up to temp quickly to ensure oil reached everywhere it needed to and also to verify no runs, drips or errors. Once it was getting warm 160-170 or so on the scanner we took it out on the road. No more than 300-400 yards into the drive it was repeatedly seeing 17psi and engine braking to seat the rings. On the off-chance the HG leaks a little it can be replaced or resealed much easier than ill-seated rings can be replaced. I double checked the torque of the studs a day or two later after it cooled down. It was spinning the tires at 75mph in 4th that cold December night so something was done right.

Everything worked out nicely aside from finding out the buttmunch who welded the head managed to warp it, so the HG only stayed sealed until the head came off a few weeks later.

[zin]

Why did you remove the head if it wasn't leaking? My experience with warped heads resulted in leaks in one case and a broken cam in another, curious about yours.

Mike

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Why did you remove the head if it wasn't leaking? My experience with warped heads resulted in leaks in one case and a broken cam in another, curious about yours.

Mike

[86Shelby]

I was trying to diagnose a noise that seemed to be coming from the exhaust cam. Turns out it was the cam gear; it loosened, slipped to the end of adjustment and rattled. While I was trying to figure it out I pushed the cam out a bit and noticed the center journals on the cam and corresponding bores in the head were torn up fierce. The cams had just been ground and made like new by Lonewolf and the bores were smooth when it was assembled. The guy who did the welding didn't use the aluminum plug I gave him when he welded the crack, so he welded the entire hole shut. I was too naive to realize what was going on when I picked it up; he was using emery cloth on the cam journals so that they would spin freely in the head. So he knew flat out that he warped the heck out of the casting but played it off. The jackhole was out of business by the time I assembled & fired the engine so all I can do is let people know since he still does machine and welding work on the side these days. The guy down in Topeka KS that Lonewolf uses was able to get the bores and the journals straightened out for me last year; so far everything looks good after a thousand miles or so.

I wasn't about to just run the head knowing about the torn up journals and hope for the best. It was all nicely rebuilt & ported by Lonewolf and I had just spent decent money on the cams as well. Too much of a financial risk to replace everything if everything went south. So I put a stock head and cams on it and enjoyed for several years.