ARP bolts

There are few 100% applicable answers from the above posts - for all the situations and conditions related to stock, high performance and racing.

The same fasteners that work for 100 HP on the bottom end are probably not the same ones you want to use for 400+ HP. How many of us have retorqued the mains - through multiple heat cycles? (I never have). How many times have I torqued stock head studs and then had to come back multiple times before they ever held the previous torque value . . . ask yourself . . . Hmmmmm . . . why is that? Did the stud/bolt continue to stretch maybe? Did my main studs stretch as well - and truthfully, I never knew it? Maybe . . .

I use mostly ARP studs for a variety of reasons. #1: When I torque them to a specific value, they hold their torque to a very similar amount to what I started with. #2: Head Studs: Given the "concentric" post up above, I used to have to align/bend the studs with a brass hammer to get them to be straight and fit my heads. And I had to hope and pray that I could get the damn heads back off the thing without having to use all sorts of "pry bars" underneath them. I've pried all sorts of aluminum heads off of flatheads - in some cases having to surface the heads as a result of the abuse they were subject too on disassembly.

When I put ARP head studs in - I have the luxury of using the Allen head socket to remove the studs - before I pull the heads. This makes disassembly a WHOLE lot easier. Once you've used this approach, you'll probably never go back to screw drivers and pry bars.

So, does one need ARP fasteners for stock or mild performance engines - heck no. But, when you put a bunch of these engines together and take those same engines apart, you'll really appreciate that you spent a few extra hundreds of dollars on studs and hardware. What did you spend on the rest of the engine . . . was this the place to save money? (In my mind, "No" - but I build stuff on the higher end of the scale).

Lastly, I think we all know that there are many different types of builds and associated budgets. What works for a low-price build is not the same as a high-end build with thousands of dollars in it. If you're building a $10,000+ flathead, having a few extra hundred dollars of ARP fasteners in it - not really a big deal.

When you're rebuilding a stock engine on a very small budget - then by all means, use whatever you can that Henry supplied - he made really good fasteners and most are better than almost anything you can buy off the normal hardware store shelf. I'd probably use Henry's studs over any "stock replacement" aftermarket product.

Enough out of me . . . time for what Pete and I call a "Martoonie"! LOL
 
I always thought retorquing the heads was because of the gasket squish and taking a set. Never heard of a bolt needing to be checked for stretching.
 
IMHO, If you are getting bolt strech on flathead head bolt @ 45 - 55 ft # torque, you have a bad bolt. They should handle many, many #'s of more torque before they could strech. I would think that the threads in the block would let go before the head bolts would even think about streching. Just sayn.
 
Take some time to look up what clamping force and bolt/stud stretch is all about. Look into how companies like ARP (and pretty much all the high-end rod builders) recommend that instead of using a torque wrench to determine the proper tightening for rod bolts - you should really use a "rod bolt stretch gauge". These gauges are specifically designed to measure the amount of rod-bolt stretch - as a means to determine the correct amount to tighten the bolt.

Also, the materials used in ARP's 7/16 rod bolts are a heck of a lot stronger than the materials used in typical head studs - yet stretch is used to determine correct fastener load. Fasteners stretch - some a lot more than others . . .

When I switched over from stock studs to ARP studs, you can feel the difference on the torque wrench. Hard to explain unless you've done it - but I assure you it is true. The ARP studs tighten in a very firm manner - unlike the stock studs and nuts (even with the correct hardened washers on aluminum heads).

Here is a little article that you'll find interesting:

https://hotrodenginetech.com/how-to...al assembly is no longer an accepted practice.
 
Bored&Stroked said:
When I switched over from stock studs to ARP studs, you can feel the difference on the torque wrench. Hard to explain unless you've done it - but I assure you it is true. The ARP studs tighten in a very firm manner - unlike the stock studs and nuts (even with the correct hardened washers on aluminum heads).
Click to expand...

Yup, it is commonly called "overkill". Absolutely essential in race engines.
 
Well using anti seize will change the bolt torque. It's been discussed here. I like anti seize. For the average joe a set of studs used or other will be fine. Watching these kids on media putting turbos and whatever on them. Ya whatever. You need to do more. Not that bolts will save the motor.
 
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Tinker said:
Well using anti seize will change the bolt torque. It's been discussed here. I like anti seize. For the average joe a set of studs used or other will be fine. Watching these kids on media putting turbos and whatever on them. Ya whatever. You need to do more. Not that bolts will save the motor.
Click to expand...

You seem to have missed the point entirely here, as NOBODY mentioned anything about "anti-seize"! ARP's "Fastener Assembly Lube" has nothing to do with "BOLT TORQUE". In fact, measuring 'bolt stretch' really has nothing to do with torque. BOLT STRETCH is a pre-determined characteristic engineered into a specialty rod bolt (for instance) that translates into a previously-stipulated, or acceptable 'CLAMPING force'. In other words, it's the force created by stretching the bolt (think stretching a RUBBER BAND) that creates the force.....NOT the torque. Torque (in THIS case) don't mean squat! The "Fastener Assy Lube" merely allows the fastener to stretch with as little undue, outside encumbrance as can reasonably be achieved. DD
 
I didn't miss anything. Even ARP has conditions for anti seize and torque settings. Guess lube is lube. I'm not making a big deal about it. A bolt sitting on the bench has very little torque and don't think it'll grow.


https://arp-bolts.com/p/arpultratorque.php


The old thought was about 5lbs on studs with anti seize. Oh course re torque the heads. Well what is old is no longer new. 99% of us can't say their torque wrench is within 5lbs accuracy anyways.



.
 
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The torque wrench was not even invented until 1924 and I'm sure a lot of garages did not have them in the 30s and maybe 40s.
A threaded bolt is the equivalent of an inclined ramp. Thread pitch determines the ramp angle. Finer threads generate the torque with less effort but over a longer distance.
Someone mentioned measuring bolt stretch and that is a definitive measurement. It does not matter about thread or lubricant, you're measuring the distortion of the bolt caused by the clamping force.
Another definitive measurement is angular movement. It might not be quite as accurate as stretch but if you turn a wrench 90 degrees on all the bolts then you are uniformly applying clamping force. Some may turn harder or easier but you are pushing on all the studs/bolts with equal force. That is given they are all starting at the same point and some manufacturers say to establish 20 ft lbs and then so many degrees to reach final torque.
Now when you are doing strictly force the use of lubricants makes a big difference. A well oiled main bolt to 95 ft lbs will exert more force than a dry bolt at the same setting. It only makes sense. Also a running torque is different than a static one. Some recommended loosening a head bolt before retorquing. You have to overcome the initial friction to get it moving. A moving bolt has less friction.
Take it for what it is worth but this is from Snap On's website about their history.
Precision Torque
In the late 1930s, Snap-on responded to the need of taking the guesswork out of applying torque. Snap-on reached an agreement with Precision Instruments, Inc. to manufacture “Torqometers.” The torqometer is a wrench and gauge combination that ensures accurate and uniform nut tightening, providing proper clamp loads and durability. Snap-on was one of the first companies to offer a complete range of torqometers, which were essential in automotive, aerospace and industry, and enjoyed a patented position in the market for many years.
 
V8COOPMAN said:
Y In fact, measuring 'bolt stretch' really has nothing to do with torque.DD
Click to expand...

A bolt or stud is in tension (stretch) when you torque the nut or bolt head. The torque is descending the "ramps" of the threaded connection and tensions or stretches the fastener.

BTW, when a stud or bolt shears straight across the diameter, it failed in tension. If it fails at 45° across, it is a torsion failure.

This is a good site for various tightening methods.

https://www.boltscience.com/pages/tighten.htm
 
I really find this discussion very interesting. If you search you will find numerous post with guys complaining about the cost of building an engine and how things cost way too much today.

It could just be me and I'll admit that, but do you really want to put faith in bolts and fasteners, that in some cases, are close to 80-60 years old? You truly don't know what has happened to these bolts prior to you reusing them.

I agree with Ronnie Roadster, Pete & Bored & Stroked, when you've got $6K-$10K in a hi-po street engine, what's another $300? In the grand scheme of things, it's nothing.

I know everyone is in a different place and some folks have a very tight budget for this hobby, but for $300 (not $500 like Speedway's price), why would you not use the best that you can get?

Is it worth fighting studs to get heads on? Is it worth the hassle of trying to get them out without the hex head? Is worth fighting leaks and other issues that inferior studs can cause?

In the end, you do need to ask yourself, how much is your time worth?

I'm seriously asking and maybe I'm wrong in my view point.
 
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I never thought this thread would be as educational as it has been. I have learned allot. In all the years I've been building engines, I've never thought of using an aftermarket fastener., back in the day ARP didn't exist so the SBC, Big Olds and those nasty Hemis got putt together with what ever the factory provided. Never lost an engine. Two e of my flatheads lost the 1,5 rod bearing, I fixed one and Walt fixed the other. He said it was from oil failure. In future builds I drilled out the supply hole in the front main bearing to the next size. The small 258 Hydro engine was the scary one, spent most of it's life between 5/6 grand and pushed the boat (Baby Ruth) over 60 mph on many ocasions. It was replaced by a 284 that couldn't go quit as ast. It was dynoed at 175 HP @ 4800. I think the major reason for this was the wrong Prop I still can't justify the cost of some of thes bolts. I use stock head bolts, Main bolts. I use SBC nuts on the stock rods. Which brings up a point. IN all my flathead race motor I use floating bearings on 21A, 91A, 29A rods and when you look at them, you wonder how they can stand the power they can produce. At present, I've designed a new intake port for the flathead. Not as complicated as it sounds. The Key to this is the chevy Vortec cylinder head which increased the power of the SBC 40HP with SMALER VALVES. Later the LS engines were born. The only thing that makes horsepower is the air we breathe. course, Nitro helps.
Gramps
 
SPS Tecnologies existed. They've been manufacturing "hi zoot" fasteners since 1903 as Standard Pressed Steel Company. They are (& were) an OE automotive supplier.
ARP just got started in the fastener business yesterday, in comparison. They are purely
an aftermarket concern in the automotive business.
 
Tim Ayers said:
.......

In the end, you do need to ask yourself, how much is your time worth?

I'm seriously asking and maybe I'm wrong in my view point.
Click to expand...

You're not wrong, but it depends on who you are. If you're a professional engine builder (who also has a reputation to protect), it's a completely different situation from the average hobbyist. I count myself as one of the latter, and like nothing better than puttering around with my stuff, taking all of the time I want. For myself, I would never consider a set of ARP studs mainly because of cost, but also because I believe they are unnecessary. I'm an "8BA guy", which makes me inclined to use bolts, but I might consider them if building an earlier engine. I've never had a problem with heads sealing and, BTW, have never had a problem removing any heads.

Any of you who have been around here long enough might remember my thread on positioning the heads using lengths of aluminum tube, the one on angle milling a head to match an incorrectly decked block, and my constant concern about properly fitting the heads to obtain optimum quench. I believe that attention to detail in such matters is a lot more important than a set of $300 fasteners. It should be known that over the years I have built up a sizeable supply of 8BA head bolts all carefully inspected and prepared, so I have a reasonable alternative.

I go into this as I believe that this is primarily a forum for hobbyists, many of whom are looking for help and information. I'd hate to have them come away from here with the impression that installing their heads is mainly a matter of purchasing a set of expensive fasteners when there are a lot of other factors involved.

I know there are many reputable professional builders on this forum as well who have their own reasons for what they use, but they already know what they need and don't need any additional assistance. What's sauce for the goose might not be suited to the gander.
 
Like has been said,,,it all depends on the application .
High horsepower or race engines deserve and require the best,,,,no way around that .

Where stock or warmed over engines can probably get away with standard parts .
I don’t blame anyone either way .

I see on Reds Headers he has some very well priced stud sets that I think are listed as ARP .
Migh5 not be the ultra top racing stuff ,,,I’m not sure .
But,,,I might give them a try .

I wish there was a register where you could see how many of these old engines are still in service,,,,,and how many cores are available for future service builds .
Im Certain there is a large number still around .

Tommy
 
The good part of this thread is that we all discussed a LOT in reference to fasteners, technology, torque/clamping force, costs, etc.. And given the application, HP levels, budgets, perspectives/beliefs - there are options to consider.

In the end, we all have to live within our (or our customer's) budgets. We decide where to spend money, where not too - in the never ending attempt to get the best we can afford - spending money how we best see fit.

Thanks to all the contributors to this thread . . . has been fun. :D
 
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glennpm ......You CORRECTLY noted my statement above (QUOTED directly below) as utter BS when taken at face value....and that is MY FAULT!

My original BS quote: "In fact, measuring 'bolt stretch' really has nothing to do with torque."

OF COURSE torque must be applied to fasteners to generate the clamping force that culminates in the event which we call "bolt stretch". And most of us realize that measuring bolt stretch of (for instance) an "ARP" fastener to see if the fastener has met a pre-determined (by ARP Engineering) 'length', is a generally-accepted, precision method of assuring a pre-determined clamping force. ARP's own site mentions "repeatability" as an important factor in using this method. Through their own manufacturing standards involving fasteners, as well as through the EXCLUSIVE use of ARP's own proprietary thread lubricant ("ARP Ultra Torque"), generally assures 95-100% of recommended preload on the first cycle. THEN.....you measure the stretch!

I had taken issue with a previous poster arbitrarily, straight out of left field, throwing "anti seize" into this picture. You might as well say that a bent nail is every bit as good as a proper cotter pin. His subsequent justification was..."Guess lube is lube." As we can see below in one of ARP's graphs, there is no "GUESSING" to it.....Lube obviously AIN'T all the same! Using ARP's prescribed product(s) essentially guarantees that a repeatable degree of torque applied....will result in the predetermined length measurements one would expect to find. And I'm really sorry for any confusion that I probably caused here, guys. DD


UT_ARP8pp.004.jpg






........
 
V8COOPMAN you have once again taken the time to illustrate actual facts I Thank You for that. ARP Ultra Torque is by far the best product for those of us who prefer accuracy where Torque is required.
Of course there's going to be individuals who would never consider spending money for such a product. The main reason COST I can hear it now can be done for less using such and such instead.
Ronnieroadster
 
That is an excellent chart and graph .
What is Detroit #2,,,,,,and I see where the graph converged at torque cycle 8 ,,,on oil and ARP ultra torque .
Good reading .
Tommy
 
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