ARP bolts

Hey my comments are not a dig on ARP bolts. They are a very good bolt. When I was swapping out a yblock on my 57 I took an idea of using grade 8 bolts from the hardware store to put in the clutchplate. I shortly came to my senses and bought some ARP shouldered flywheel bolts. No I'm not concerned about using ford bolts or other suppliers, within reason.


But to say you can always torque within 5lbs is interesting. My last tourque wrench was 300$ 100-300# Changed out my brothers new truck wheel bearings.
 
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Didn't answer how you calibrate your torque wrenches. Last I recall torque settings are units of foot-pounds. It doesn't matter. I was just asking as I don't know and hoped you can help.
 
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Torque is correctly expressed in units of pound-feet. foot pounds is the measurement used for work. I know they are both the same but the scientific community did it that way for some reason.
 
Frank Miller said:
Torque is correctly expressed in units of pound-feet. foot pounds is the measurement used for work. I know they are both the same but the scientific community did it that way for some reason.
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Too pull teeth or to put a foot in a pound of mouth. Always best too not take the time to educate. Okay that makes sense, frank. thanks, i wonder if I use old bolts and they can take it, granted my flathead is not going down a runway... have I made a mistake.

https://www.enginelabs.com/news/torque-talk-pound-feet-foot-pounds-one/

I'm still asking about calibration of torque wrenches also.


.
 
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That is an excellent article. Even as a mech eng I learned something. A Gr 8 bolt is a Gr 8 bolt no matter who makes it. This of course assumes manufacturers abide by recognized standards and quality control procedures. As such, an ARP Gr 8 bolt is no better than anyone else’s Gr 8 bolt although they may look prettier.
 
No article included on your post. I'm not sure that is true. also grade 8 bolts are brittle and don't give to sheer. Just saying.
 
Ziggster said:
That is an excellent article. Even as a mech eng I learned something. A Gr 8 bolt is a Gr 8 bolt no matter who makes it. This of course assumes manufacturers abide by recognized standards and quality control procedures. As such, an ARP Gr 8 bolt is no better than anyone else’s Gr 8 bolt although they may look prettier.
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I don’t agree. As an experiment, go buy a grade 8 bolt from Home Depot and then buy the same sized grade 8 bolt from ARP bolt from a place like Allen’s Fastners. Once you do and compare, tell us which one was better. Thread and bolt quality and consistency. How accurately the head of the bolt is sized and machined.

This of course assumes manufacturers abide by recognized standards and quality control procedures.

This can be a big assumption. There are a number of articles that test hardware store grade 8 bolts have been proven to really be around grade 5 or less. Just because it’s gold in color, doesn’t mean it’s an accurate grade 8 bolt.
 
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ARP head and main studs are not Grade 8 - lets start there. Their tensile strength is roughly 190,000 PSI (depending on the application and material) - Grade 8 is around 150,000. But, there is a lot more to it than just the grade - consider material, material sources, manufacturing processes, thread design, heat treating, etc.. ARP studs have rolled threads - you won't find those when you go to Tractor Supply and buy Grade 8 bolts.

By no means am I saying that every flathead needs ARP hardware (I am not in Sales!), but there are many differences between regular Grade 8 bolts (and who knows where they are manufactured, what type of materials, what processes, etc), vs ARP hardware.

Here are a couple links in case you're bored:

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

https://www.hotrod.com/articles/why-use-arp-bolts/
 
Taken from the article B&S's posted.

Simply stated it comes down to quality, both of the materials used and the process of making the various fasteners. Everything is made in the United States, and ARP always uses top-shelf materials. For example, take the ever-popular 8740 chrome moly steel. It comes from the mill in four different grades. The lowest grade is commercial, followed by aircraft-quality. ARP, however, only uses the top two grades (SDF and CHQ). These grades cost twice as much, but it's why they have a reputation for "zero defect" quality. In short, not all 8740 steel is the same, and this is why an 8740 fastener from ARP will cost you more than a Brand X fastener even if it also states it's 8740.

Take from article to support my point regarding overall machining quality:

For example, when ARP makes 12-point hex nuts, its process with the automated threading equipment turns out a nut with an accuracy of 0.001 inch! That's five times higher than the aerospace standard. It also means there'll be a perfect fit between the bolt/stud and the nut.
 
It's kind of like running a nut up and down a 10-32 screw. It seems to fit pretty good and will do the job. Now screw a micrometer - 40 threads per inch - and feel the difference in a precision machined screw.
The question is how much is really needed? The answer depends on what margin of safety you want to run.
 
Bored&Stroked said:
ARP head and main studs are not Grade 8 - lets start there. Their tensile strength is roughly 190,000 PSI (depending on the application and material) - Grade 8 is around 150,000. But, there is a lot more to it than just the grade - consider material, material sources, manufacturing processes, thread design, heat treating, etc.. ARP studs have rolled threads - you won't find those when you go to Tractor Supply and buy Grade 8 bolts.

By no means am I saying that every flathead needs ARP hardware (I am not in Sales!), but there are many differences between regular Grade 8 bolts (and who knows where they are manufactured, what type of materials, what processes, etc), vs ARP hardware.

Here are a couple links in case you're bored:

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

https://www.hotrod.com/articles/why-use-arp-bolts/
Click to expand...

We are speaking the same language but from two ends of the spectrum. I’m going from the perspective of a standard(s) that categorize specifications for bolts to which manufactures must abide by, and you are assuming some or most don’t. For example, you infer hardware sold at places like TSC or HomeDepot are not what they claim to be. Maybe, maybe not. For example, Hillman sells to both, and they are not some flight-by-night operation. I will say, back in the day though working at General Motors Diesel Division there was a huge issue NA wide with sub-standard offshore hardware. I recall barrels of bolts etc, being discarded rather than taking a chance that it might be “ok”.
 
JM2 cents! I gotta go with Ol’ Ron on this! He’s built a boat load of engines so while it is his opinion it’s VERY EXPERIENCED opinion! I have only had & worked on 1 Ford Flathead (1949) 8BA), I have built or torn down for repair probably 100 mixed Mfgr engines, all overhead valve type. To say ARP are the best probably true. If ur building a sponsored race car or got the green w/o a sponsor & racing every weekend where the costs are secondary to safety & breakdown due to very over top extreme repetitive conditions, then absolutely buy ARP! To say a bit more expensive is a misnomer! I’ve never used ARP as I could buy a good running used engine for the price of a set of ARP head bolts. I always used new OE hardware where strength mattered from reputable Auto Parts stores @ 20% of the cost of ARP’s hardware. Also never had a Hardware failure on any I worked on. OK, that is just opinion from me. a nobody but I can’t think of any auto mfgr’s who use ARP in their vehicles (I may be wrong on special order Perf cars like Shelby Mustangs for obvious (race car) reasons! Hey it’s a free country so far so if cost isn’t a factor go for it:eek::D
 
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There is no better feeling than being able to buy beer for the crew after you win and you don't win with second hand oats.
 
Everyone is basing price on the Speedway catalog. They do not cost $550. I will try to find my receipt from Allen’s fasteners
 
The head stud kits that cost $550 include their high-strength stainless alloy solid acorn nuts. These are made from very expensive material. There are the parts that drive the price way up.

If you want real acorns that don't rust - these are the ones to have . . . but you'll pay for them. They're a real nice product - but not necessary in the least - unless you're looking for the 'bling' factor.

B&S
 
What do you torque these $550 studs to? Are you aware of the facte that the block is only 1/4-3/8 thick in some places. The reason I torque the heads to 45 ft/lbs is to prevent warping the block. I do this for several heat cycles to normalize the the clamping force over the intire area of the block/head combination. Even in a blown engine, the studs/bolts are not the issue, and the stock studs/bolts will work just fine. However, I could be wrong!! so buy them, you'll feel better,
 
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