Temporary Studs for Cylinder Head Installation

...That's a Great Idea! I use the Short Tube Locating 'Dowels', two per head. I don't see them in the photo. I also use ARP Head Studs, for a 40% Greater Clamping Force (Fine Treads on the Nuts).

MJ

Marlin, I took the photo before installing the dowels.  They are in place now.

...There They Are!

MJ

Steve,

Why use studs as guides only? Why not just use head studs to bolt the heads to the block?

Hi David,

It's a little tight in there and at first I could not determine if studs would allow installation of the heads.  Now it looks like they could work.

Also, none of this is cheap.  I already own ARP head bolts that cost $93.  A set of ARP studs is $171.  And there might be complications with the studs.  I am going to take the low road and just stay with what I have.

Make sure you cut a groove in the center on the end so you can get a screw driver on it to help you back them out

...I am here to testify that the Iron heads can be installed, OVER All 10 Head Studs and onto the Engine, while the Engine is still in the car! I can Lean Way-IN over the fender to lift the Iron Head. It WILL clear the Studs...the Coolant 'pressure/serge' Tank must be removed, out of the way. FWIW

...And don't forget, Fender Blankets, NO Belt Buckles, Zippers and NO Denim Rivets!!

MJ

On the passenger side you might be able to leave the surge tank in place and use shorter temporary studs.

Marlin, I just noticed that the permanent ARP studs are fine thread at the top.  That is a definite advantage over the coarse thread bolts in the stock configuration.  It seems like the coarse thread bolts complain a lot when torqued 105 pounds.

Steve,

That's because, as torque increases, the bolt still needs to turn in the threads. It's hard on the bolt and hard on the threads in the block. With studs, the coarse threads are being tightened but they don't need to turn at the same time. The torque value is more accurate with studs too.

You would never use head bolts in an aluminum block.

Fasteners, like head bolts/studs and con rod bolts work by being stretched to a specification for a given assembly. That's how they keep the parts together in the very dynamic and highly stressed environment they live in. Some race engine shops use bolt stretch gauges for con rod bolts. Torqued to a spec approximates the required stretch for that bolt. In most cases the engineering has been done so you know the correct torque spec for your application.

Using a little lubricant under the head of head bolts is a good idea unless your application calls out for a dry assembly. We used Cosworth rods in some of our race engines. The rods were supplied with a pouch of lubricant. I think it was a moly lube of some kind but they would never disclose what it was. Their instructions were very explicit: MUST use the Cosworth lube under the head and NEVER get any of it on the threads, use light engine oil on threads. Lube helps achieve the correct clamping force for the spec torque applied. A dry assembly can have enough friction so that the torque wrench reading is to spec but the needed clamping force (stretch) isn't.

Steve, You said, "It seems like the coarse thread bolts complain a lot when torqued 105 pounds". Do you use lube under the heads? The threads shouldn't be dry either. Make sure the bolt head seats are not gouged or distorted. Before installing the cylinder heads confirm the head bolts easily screw into their respective hole and to sufficient depth.

Bolts vs studs is a long discussion.

Thanks Mike.

The head bolts and washers look like new and there is no gouging or distortion on the head bolts or the cylinder head itself.  Prior to cylinder head installation I clean out the threads in the block to remove old lubricant and crud.  Next I dip the top of the head bolt and its washer into a cup of engine oil as its lubricant as well as the threads and then remove the excess oil on the threads in an effort to not contaminant the head gasket.  Even after doing all the above there is just a bit of a creak on some of the bolts when final toque is applied.  It is not a substantial feel or sound but it certainly happens on some of the bolts.

Head bolts do not have an infinite amount of reuse. They should be replaced with new ones after three or four uses. In this case, use means re-installation, not mileage.

You really don't need head studs on a stock spec engine. The 105 comes from the use of an original Boss 351 assembly and the combination of the specific head gasket originally used on them.

That engine had an advertised static compression ratio of 11.5:1 and the 105 torque is for race use with a high  compression application and the specific head gasket recommended. Typically a CJ assembly spec engine is fine with a 90-95 lb-ft spec and a current Fel-Pro.

Essentially, the 105 lb-ft spec is now obsolete.

Use the dowels to locate the head on the block as you install the heads.

I agree with Doug. Stressed fasteners don't last forever.

@stevebuchanan posted:

Marlin, I just noticed that the permanent ARP studs are fine thread at the top.  That is a definite advantage over the coarse thread bolts in the stock configuration.  It seems like the coarse thread bolts complain a lot when torqued 105 pounds.

...The Fine threads of the Nuts account for a 40% Increase in 'Clamping Force'.

NO! You do Not 'Need' Head Studs. Unless you want More Treads with-in the Block Full Depth, More Rigidity, more security from 'Walking', the increase in Clamping, and a Stronger Fastener, greater Insurance against Blown Head Gaskets. Or, You are working with a Aluminum Block, it's a must do.

Torquing the Nuts to 90-95 Ft/Lbs Will Allow the Head Gasket to Blow-Out, some time, while at a WOT. It happened to Me Twice!! I called up ARP to get a confirmation on the Required Torque Setting. The Technician replies...Studs for Iron Heads on a Iron Block 130 Ft/Lbs. That was ten Years ago, No Problems Since. Yes! This is right on the threshold of Ripping the Threads out of the Block.

The Gentleman is Right...Never use Head BOLTS on a Aluminum Block!! You Will rip out the Threads! With the Studs, I imagine, then, the torque would be at your 105 Ft/Lb.

A WARNING!! When you feel the need to 'Clean' the Threads in the Block, Never Use a 'Thread Cutting' TAP! No 2 Taps, cut the same thread Clearances. Running a 'New' Tap down an Existing threaded Bore will cut the Threads, Again! Metal will be removed, the result is a 'Looser' fitting fastener (Bolt or Stud), that is permanent and not fixable! To properly clean threads in a bore, take a Head bolt, grind a slight 'Cutting edge' on the first few threads, and run that Bolt down to clean out all debris, and 're-dress' the threads, With-Out Removing additional Metal.

All the Best

MJ

P.S. Imagine leaning into the Engine Bay and Torquing Head 'Nuts' to 130 Ft/Lbs. I proved it can be Done! And I did Not remove the Decklid!!

...there is one more Warning I must add, concerning Head Studs installed in the Cleveland IRON block. The 'Instructions' recommend screwing the studs into the Block 'Finger Tight'. I did not like this as when torquing the Nut onto the Head and stud, there is nothing to prevent the stud from screwing in further as one is trying to obtain a final torque. I chose to screw them in and with a rachet (using the jam-nut method) , tighten the stud up, 'Snug'.

The warning here is...if the stud were to be installed and Torqued beyond this limit, there is a great chance of breaking the Bottom of the Bore Into the Water Jacket of the Block! This would Not be a Problem when using Head BOLTS. Some of you may have already found after removing the head Bolts and Head, one or more Bolt Holes, have leaked Coolant! The Major reason Studs (and possibly Bolts) should have the Threads coated with a massive amount of Sealant before installing into the Cleveland Block. Note, Teflon Tape Won't do the Job.

...I Would Change Over to ARP Head Studs Again without Hesitation! A Stud is just More Rigid, Stronger set-up, with More Threads inserted into the Block, than a 'Bolt'!

MJ

The amount of clamping force needed is related to the specific needs of the head gasket.

The head literally floats on the head gasket. Sealing is not attained by crushing the gasket.

This is seen more clearly in using an aluminum head on an iron block where the two do not have the same rate (coefficient) of expansion.

Aluminum heads for instance, do not require more clamping force. In fact they will show more deformation then iron heads will, but at some point you no longer are just crushing the gasket, you are crushing the head.

If say you choose to use a Fel Pro head gasket, the torque numbers are given in the installation instructions. They will not benefit from more clamping. In fact that is detrimental to their function.

In the case of head studs, they are a different steel alloy then the head bolts are. You need greater torque on them simply because you are stretching the studs. It is not applying more compression to the gasket then the bolts are.

You can use studs on iron heads if you want to but their benefit is largely to the aluminum heads to reduce distortion to the head itself.

Because of the normal heat/expansion cycles the gasket sees in its lifetime, you have to presume that at some point the gasket wears out. That number is not given but personally I would not still rely on an original 50 year old gasket especially with old gasket technology.

If you show signs of water leakage on the end fasteners check the head for straightness and change the head gasket and put in NEW head bolts. The head gaskets wear out. The bolts do also.

Forget about the 105 torque. It is long gone. It was specifically for the "special" Reintz gasket of the early 70's. That's old tech.

I WOULDNT USE Perma toque blue head gaskets i would recommend Graphite or the more expensive. Cometic