SKU: 44455937608

ARP Head Stud/Bolt Kits

Sale price$142.14 Regular price$157.93
Save 10%

Pay in installments of $39.48 with ShopPay, AfterPay and Klarna

Shipping Estimate
USA
  • USA
  • CAN

Ships within 48 hours · Estimated delivery Jul 30 - Aug 4

Promo Codes Available:

For Your Every Summer RSVP, with Code: SUMMER15

Description

ARP Head Stud/Bolt KitsIt is for good reason that virtually every top professional engine builder relies on ARP Pro Series head studs for their all out competition powerplants. Simply stated, theres not a better stud setup on the market today. For openers, ARP uses a premium grade 8740 alloy that is rated far superior to aircraft quality. Each stud is placed vertically in special racks and precisely heat treated to 200,000 psi. This procedure ensures complete heat

It is for good reason that virtually every top professional engine builder relies on ARP Pro Series head studs for their all-out competition powerplants. Simply stated, there’s not a better stud setup on the market today.

For openers, ARP uses a premium grade 8740 alloy that is rated far superior to “aircraft” quality. Each stud is placed vertically in special racks and precisely heat-treated to 200,000 psi. This procedure ensures complete heat penetration and the results are far superior to those lesser quality studs from other manufacturers who just dump pieces in a basket and hope for the best.

Following heat-treat, each stud is centerless ground to make it as close to perfectly concentric as possible. This procedure involves about ten very slight cuts and results in an exceptionally straight part. It’s important to note that lesser quality studs are not even centerless ground – the material is thread rolled in bar stock form (mostly before heat-treat, when the material is easier to machine). Because ARP studs are manufactured to such exacting tolerances, you will note that gaskets and cylinder heads literally glide into position and are perfectly aligned – something that won’t happen with inferior quality head studs.

ARP studs are thread rolled after heat-treat, which gives them about 1000% (that’s ten times) better fatigue strength than those studs that are threaded prior to heat-treat (a very common industry practice). It costs a lot more to do it this way, because it’s tough on tooling, but the results are well worth the extra effort.

You will also note that ARP offers specially undercut studs for several engines. This procedure (done only to the shorter studs) more equalizes the “stretch” of both studs, which makes for a more consistent clamping force – and one that compensates for head gasket compression when the cylinder heads are installed. This helps prevent blown head gaskets, and assures optimum engine sealing!

Premium quality heat-treated 8740 chrome moly steel head stud kits are available for most every domestic and import applications.

You won’t find a better quality stud on the market from any other source. Look for ARP stamped on each stud as your assurance of quality.

Clearly, ARP Head Stud/Bolt Kits are the best on the market today, and the favorite of leading professional engine builders in all forms of racing.

HIGH PERFORMANCE SERIES
High Performance head bolts are available with a reduced wrenching hex or 12-point and wide area flanged head that eliminates the need for valve train removal to facilitate cylinder head retorquing. All High Performance Series bolts are 180,000 psi (which is 15% stronger than Grade 8) and kits come complete with hardened parallel-ground washers.

PRO SERIES
All Pro Series bolts are cold-forged to ensure molecular integrity, heat-treated prior to thread rolling and machining, and are rated nominally at 200,000 psi. ARP Pro Series head bolt kits are application specific – designed for use with typically competition only components. These fasteners deliver superior strength and meet the ARP “ZERO defect – ZERO failure” quality standard. Hardened and parallel-ground washers are included with each kit to ensure even load distribution and accurate torque readings. All Pro Series head bolts have a reduced wrenching hex or 12-point head and wide area flange to eliminate the need for valve train removal for cylinder head retorquing and permits the use of larger diameter valve springs. Most applications have undercut short bolts that can help eliminate head gasket failures through providing more “stretch” to compensate for the additional compression of gaskets.

CUSTOM AGE 625 PLUS®

This newly formulated super-alloy demonstrates superior fatigue cycle life, tensile strength and toughness – with complete resistance to atmospheric corrosion and oxidation. ARP is the first to develop manufacturing and testing processes for fasteners with Custom Age 625+. Best of all it is less expensive and expected to soon replace MP-35 as the material of choice in the high strength, super-alloy field. Typical tensile strength is 260,000-280,000 psi.

 

Head Studs vs Bolts
On many street-driven vehicles, where master cylinders and other items protrude into the engine compartment, it’s probably necessary to use head bolts so that the cylinder heads can be removed with the engine in the car.

For most applications, however, studs are recommended. And for good reason. Using studs will make it much easier to assemble an engine (especially a racing powerplant which must be serviced frequently and quickly!) with the cylinder head and gasket assured of proper alignment.

Studs also provide more accurate and consistent torque loading. Here’s why. When you use bolts to secure the head, the fastener is actually being “twisted” while it’s being torqued to the proper reading. Accordingly, the bolt is reacting to two different forces simultaneously. A stud should be installed in a “relaxed” mode – never crank it in tightly using a jammed nut.

If everything is right, the stud should be installed finger tight. Then, when applying torque to the nut, the stud will stretch only on the vertical axis. Remember, an undercut shorter stud will have a rate similar to a longer, standard shank stud. This provides a more even clamping force on the head. Because the head gasket will compress upon initial torquing, make sure studs and bolts are re-torqued after the engine has been run.

Shipping Notes
  • Free Standard Shipping on $100+ Orders to the USA.
  • Except Preorder products are shipped in 48 hours.
  • Delivery to the USA:
  1. Standard Shipping : 3-10 business days
  • If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
  • We offer a 30-day return/exchange service after receiving.
  • Final sale items are not eligible for returns or exchanges.
  • To process your return/exchange, please contact us at [email protected]
  • Please click here for more details>>> Return & Exchange Policy
SKU: 44455937608

Discover Niche Categories That Outsell

Top-Converting Item to Boost Your Average Order

4.4 ★★★★★
Based on 6 reviews
Sort
Highest Rating
Newest First
Oldest First
Product Reviews
H
Verified Purchase
Heather W
Lake Worth, US
★★★★★ 5
Great toys
Pattern Name: Cow Chew Toy Set
Overall these toys are great. My puppy has many toys, but the rope toy included in this set is by far his favorite toy. He does enjoy the other toys as well. The only one I did not like was the one with the bell in it. That seemed like a terrible choking hazard for a puppy. I gave that toy to a friend who owns a cat. Other than that, I would recommend these toys. They have held up great for 3 weeks so far.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on November 11, 2024
K
Verified Purchase
Kathryn
Cuba, US
★★★★★ 5
Best chew toy ever!
Size: Small, Color: Textured Ring, Size: Small, Color: Textured Ring
This bone is indestructible. Finally a toy that doesn't get chewed up to pieces.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 5, 2026
L
Verified Purchase
Laurel
Natrona Heights, US
★★★★★ 5
Heavy duty, excellent quality
Size: Small, Color: Textured Ring, Size: Small, Color: Textured Ring
I trust the Nylabone brand and would not buy a cheap substitute to save a few bucks. This ring is heavy duty. I got it for our 9-week-old puppy and it keeps her interested and entertained with all the little nubs. She uses it more as a toy than something to chew on, tossing it around and mouthing it. It's very hard so I'm not worried about her being able to chew off any little pieces at this point. This satisfies her for now and helps to keep her busy and reigns in some of her puppy energy. Recommend!
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on March 9, 2026
N
Verified Purchase
Nunya B
Phoenix, US
★★★★★ 5
Strong
Size: Small, Color: Textured Ring
My French Bulldogs have really strong jaws and are aggressive chewers. These really are sturdy and last a good amount of time. I replace every couple of months and they are one of my dogs favorites and easy for them to hold onto.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on April 25, 2026
M
Verified Purchase
Marie Phillips
Grantham, US
★★★★★ 4
Durable Chew Toy That Actually Holds Up to Strong Jaws
Size: Large, Color: Bundle
This is a reliable option for a heavy chewer, especially for a large breed with a strong bite. The material feels tough and well-made, and it stands up well to consistent chewing without immediately breaking down like softer toys tend to do. It also gives a bit of dental benefit by helping reduce plaque and tartar buildup during play, which is a nice bonus since brushing isn’t always realistic. The textured surface keeps it interesting enough to hold attention for a while, and it doesn’t splinter or create a mess. Overall, it’s a solid, durable chew toy that works well for strong chewers who tend to destroy most standard toys quickly.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 6, 2026

recommand products