These head studs and rocker arms work exactly as advertised. The build quality is top-notch, and you can tell these parts are engineered to handle serious pressure. Everything was individually protected and arrived neatly packaged, which really shows the attention to detail. The installation was straightforward, and the milled rocker pedestals fit perfectly. Highly recommended for anyone looking to upgrade their 12V Cummins build.

They are holding 70 psi of boost with no issues. Everything came neatly packaged and every thread was individually protected. The milled rocker pedestals looked nicer than oem and work perfectly. For the price of the kit and what you get I highly recommend it.

The install was easy! The performance is much better than stock!

These are made with great quality and have been performing well within the forst month of installation.

Great fasteners going to install these once the motor is out .. same quality as arp thanks xotic performance!!

Exhaust manifold stud kit was great!!! Installed so easy.

This M12 x 1.75 thread chaser worked perfectly for cleaning up damaged and dirty threads on my 24V Cummins. It threaded smoothly, removed the buildup, and restored the threads without cutting away unnecessary material. The tool feels well-made and saved me from having to replace the part. Definitely worth keeping in the toolbox.

This M12 x 1.75 thread chaser worked perfectly for cleaning up damaged and dirty threads in my 24V cummins. It threaded smoothly, removed the buildup, and restored the threads without cutting away unnecessary material. The tool feels well-made and saved me from having to replace the part. Definitely worth keeping in the toolbox, will probably use on other projects as well.

Just want to say how impressed I am with the bolt … arp quality if not better … this will go great with my 6.2 cam build … and ati balancer… should be a great fit!! Thanks XOTIC PERFORMANCE!!!!

I ordered a set for my service truck because my hired hand swears by these over the competition. I took his advice and man, I am so glad I did. We run a diesel shop and going forward, I won't buy anything other than these. Great construction, thorough instructions and actually include the tools necessary for the job. Keep up the great work guys! I will be ordering again.

Great product!! Everything came as pictured with tools and instructions I will be using this on my 6.2 ls motor that I’m rebuilding so this will be a nice piece to add thanks xotic performance!!

Great bolts came as pictured with instructions and help thanks xotic you rock

Good quality

Middle head studs dont fit for the non vtec ones. They need 2 slightly longer head studs.

These studs are the next best thing compared to the big name!!! Way nicer than all the other more budget friendly studs out there!. We will see how they do with 30lbs of boost!

Great product very straightforward and easy to install

My order arrived only a few days after arrival. At half the price of the other “brand”, this was a no-brainer. My stock OEM head bolts were stretched so these will be a big upgrade.

Work great so far

Straightforward and easy installation is definitely holding up to what I’m using the truck for great product so far!

2006 Ford f350 4x4 cab and chassis, worked great. Just what the truck needed. The stand pipes are hard to separate but with some muscle they are able to come apart. The green o-ring was the only part I had no idea on where it went.

I haven't installed them yet, have to replace the camshafts. bad rockers arm deep grooved the lobes

I've been running these in my truck for almost a year without an issue.I had just done a bunch of performance work to my truck (injectors, turbo, CP3, tune, etc) and blew a head gasket. @truckmaster07 recommended this brand and I see why. Obviously well made. Comes with sockets, an extra long Alan wrench, grease, and VERY clear installation instructions. And the packaging is an experience by itself. So much attention to detail. Not to mention the fasteners have probably the best finish I've ever seen on bolts, nuts, and washers (I'm a quality Engineer with machining background).

Easy to install first time using them like how everything came in box and prepared nicely packaged

I used this on a big block setup, and the hardware felt right for the job. The weight is what I would expect from real engine fasteners, and the material feels strong and properly machined rather than lightweight or questionable. The 12-point heads are clean, and the fit was solid during installation.This is not the kind of part where I want to gamble on poor quality, and these felt consistent from bolt to bolt. The versatility is good across the listed older big block applications, but I still checked fitment carefully before using them because engine parts are not something to guess on. Installation was straightforward, and the instructions/spec information were clear enough to follow with normal engine assembly procedures.The durability is the main reason I like them. They feel like they are made to hold torque properly, and the finish looked clean out of the package. The value is good compared with piecing together questionable hardware, especially when doing a repair or build where dependable fasteners matter. I would use them again.

The intercooler pipe is fantastic and a huge upgrade over the stock pipe. Had a small hiccup and the service department was on it, took care of everything, and made sure it was all taken care of. Will definitely buy more products from them!