Ol´Ron,Pete,Gosfast and other experts ....

[32phil]

Not looking to start a fight here. Just a suggestion.. in general.. if folks are having a problem/looking for info. they should use the search function....
As far as Studs VS. Bolts......This topic has been covered very well previously.
To get the complete picture and see the previous posts use the search feature and you will see the previous discussions.
If you search for posts by 32phil (me) you will find a discussion (March 2015) concerning studs vs bolts..... lots of knowledgeable folks replied ....some good info there.

[Ronnie]

This will keep the inquisitive mind going.

https://www.google.ca/search?hl=en-C...pe=&as_rights=

R

[GOSFAST]

I wanted to add some add'l input yesterday I just ran out of time!

Just about all factory head bolts, regardless of brand, have sort of "built-in" washer when mfd. The issue with this design is the fact the "washer" area is not large enough to last over time and use! Eventually they "dig-in" to the heads and actually lose some of the "stretch" when this happens. Not much but some! We feel this leads to future head gasket failures, not in itself, but along with other issues!

Below here are a few shots of what we find on disassembly, mostly the SBC's on resto's, but others also! In the one photo I show the "pieces" of the head casting where that washer section of the head bolts eventually causes the casting to "break-away" from the bolt hole and look like small washers instead of the original castings.

For years now we've been using ARP washers under ANY fastener, bolt OR stud. They already belong with the stud setup but we do them on the bolts also.

These washer's (they are actually an aircraft industry designed piece) are small enough to be almost entirely "invisible" when assembled BUT carry and spread-out more load than the washers built into the bolts!

They are NOT the same sizes supplied with the standard ARP kits, they are normally found on aluminum connecting rods! We do have access to various sizes through ARP!

Many of these fastener/gasket issues caused us a few years back to begin pinning the blocks, heads, and gasket together using the SBC as an example. One other reason for the pinning deal was the fact all the aluminum head mfr's decided to "enlarge" the head bolt holes due to "complaints". We had spoke to Edelbrock back then and told them this not a real good move since nothing was "locating" the heads or gaskets, it all fell on deaf ears!

Thanks, Gary in N.Y.

P.S. Here's a couple shots of the issues we encounter! On the SBC"s we machine the bolt holes down enough to get past the broken casting teh use some .125" thick washers. These are different from the ones I mention above here. The remnants stapled in the plastic is what we find on on most SB's. The Flatheads aren't as bad, but we make them "better" also! The top/left shot below here is an original Flathead bolt.

[Bored&Stroked]

I'm not sure if anybody mentioned it, but one reason that I prefer studs is due to the fact that you typically get better (more accurate) torque readings on fine threads with hardened washers and associated nuts. I use ARP studs on all my performance builds - for three reasons:

1) They have a hex allen wrench receiver in the top of the stud - so you can take them in/out one at a time (without a stud puller).
2) Due to the quality of the materials and heat treating, they don't stretch nearly as much as Ford's original studs - which means I don't have to re-torque them as much.
3) I use teflon sealer on the coarse threads in the block - have had very good luck with putting the studs in the block, letting them sit for a few days and then putting the heads on. I don't have any water 'weeping' issues past the coarse threads.

Lastly ARP sells a complete stud/washer/nut kit that has hardened stainless acorn nuts. Yes - it is very expensive . . . but dang, do they look good (and they cover up the hex-topped studs) as well as perform well!

Of course the engines I build are on the top-end of the performance/HP scale, so I like to have as consistent of a clamping force as I can get.

[Kube]

Originally Posted by 51 MERC-CT

Gee, I wonder if the studs were so much better, why from '48 on, to my knowledge did all flatheads as well as later OHV engines successfully use bolts?

Pretty simple ... cost. try to remember these companies shave fractions of a cent whenever possible. Seriously...

Within this thread and in my opinion, GOSFAST has pretty much "nailed it".

[Ronnie]

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Cost or not the bolts will work fine @ 50lbs. Spend the extra cash on a good ignition system that will get results studs won't get you anything. It'd your dime do as you like.

R

[Bluebell]

Surely the value in the stud is about the ramp angle of the UNF thread (nut end) which could not be used in the cast iron deck.
The UNC thread (deck end) has a much steeper ramp angle (partly) because of which a less consistent result is achieved with the torque wrench. Added to this, "torque by bolt" is not the same as "torque by nut"
The deck of the flathead motor is a known weak point and the use of studs will possibly help to protect and maybe lengthen the life of a particular block.
From an engineering and reliability point of view, the stud wins. The bolt is cheap to produce and very convenient when it comes to ease of clean up of the gasket face.
The introduction of the head bolt was an economy measure which if designed today, would have surely been "torque to yield" (as nearly every other head fastening system is of late)

I'm still waiting for Pete and Ol' Ron to chime in.