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Part number: 300-8243
Product Details
ARP 300-8243 Perma-Loc Rocker Arm Adjuster - Pack of 16
Products specifications
For Use with Stud Girdle No
Minimum Rocker Slot Width (in) 0.550 in.
Outside Diameter (in) 0.550 in.
Overall Height (in) 1.200 in.
Quantity Sold as a set of 16.
Rocker Arm Nut Style Polylock
Rocker Arm Style Full roller
Rocker Stud Thread Diameter 3/8-24 in.
Size 1.2 x 0.55
Thread 3/8-24

One of the more aggravating things found in many high performance engines is constantly having to re-adjust rocker arms. Until ARP introduced the patented Perma-Loc rocker arm adjuster, there wasn't a "poly lock" on the market that you didn't have to continually tighten. There are several important reasons why ARP's exclusive Perma-Loc rocker arm adjusters won't loosen like others. First, the adjuster body is heat treated all the way through (not simply case hardened), which eliminates the thread "movement" common to others. Secondly, the threads are machined exactly perpendicular to he bottom of the adjuster, so it seats evenly and applies pressure on a full 360 degree circle. Lastly, the set screw is machined flush on the bottom, not pointed, so it will have optimum contact on the rocker arm stud. Perma-Loc adjusters are also easy to use, because the compact 12-point head is designed to hold your wrench in position while you lock the set screw with an Allen wrench.

  • Designed for aluminum rockers, and features an overall length of 1.200, a thread size of 3/8 - 24, and a body diameter of .550; sixteen adjusters per package
  • Bottom is flush-ground perpendicular to the threads, so it seats evenly, and the set screw has flush-machined tip for optimum contact and seating on stud
  • Threads are precision CNC-machined exactly perpendicular to the bottom of adjuster to ensure an optimum seat, even pressure, and maximum engagement
  • Forged in-house from grade A 8740 alloy chrome moly steel and heat-treated throughout for a 190,000 psi tensile strength, not simply case hardened like others are
  • Exclusive 12-point head, with special shouldered "stop" to hold the wrench, eliminates the need for special adjusting tools
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Parts were actually in-stock unlike every other retailer I tried. Quick shipping too.
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Recent purchased new Hawk HPS brakes for my 2010 Hyundai Genesis Coupe 3.8 Track.

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Not only did I experiece great customer service and quick shipping/processing, Autoplicity also had the LOWEST price of any vendors for these parts I could find online.

Great service + Great pricing = Match made in heaven!
The best price I could find and it arrived in 2 days! I'll be doing business again.
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