After years of engineering around the M156/M159 engine platform, we have finally released many of our upgraded engine products. We have also witnessed many AMG owners dealing with dreadful coolant leak/head gasket issues. This is finally the solution for those looking to make big power, or just simply maintain their engine by using the best hardware in the industry.

We at Weistec have partnered with ARP to design and create the strongest and most durable hardware for the M159/M159 heads. These are a 625+ material and also include 12 point fasteners.





Pricing is $899.95

Please call or email us for further information. Thank you all.

http://weistec.com/m156studs.html

Weistec Engineering

What are these bolts made out of?

The material name is Custom Age 625 Plus which is a type of bolt that ARP manufactures for high strength. It is a mixture of Stainless Steel, Nickel, chrome moly, and other proprietary materials that ARP uses in their hardware. It is among the the best bolts for these types of applications. Thanks!

Weistec Engineering

Ive actually heard of custom age 625 alloy, very strong and very corrosive resistant. if I'm not mistaken they have a working heat capacity of around 2000°F.
Good stuff Weistec. Would definitely get these (for extra security and peace of mind) if I were running forced induction.

Jesus that is expensive for ARP's.

Glad the option is available though.

How many hours does it take to R&R the headgaskets and install the bolts?

About 15 hours

Like Weistec, ARP is another California firm that knows its business.

http://arp-bolts.com/pages/technical_metallurgy.shtml

When my heads come off, this will be getting done.

This is a great add on when you get your Race ported heads

As a retired engineering Liaison , I was involved in many new developments of engine platforms. Where we would use an existing Crank-shaft ( Engineering & Tooling was already expensed out) Saved Money. But would run into issues of holding a newly developed heavier Flywheel with a built in Harmonic balance in place at 5000 rpm. ( Second order issues ) at 5150 rpm & higher or lower it was OK. But if was left at 5000 rpm there it would shear , bolts or studs , over a 3 hour dyno endurance run. We did not have time to retool the Crank to get the motor into production. So we went with ARP 625 studs & their matching washer & Nuts. This got us 3 more years down the road . to the annual retooling time. ARP has a wide variety of solutions that work well. It was expensive , but we made the introduction date.
Cheers _PTEngineering

Thank you guys for the interest and comments, and thank you James for helping answer some questions. James is correct about install time. They have performed most, if not all modifications we offer on customer cars.

The Custom Age 625 Plus head stud is extremely strong and one of the best bolts for changing temperatures, and this is why it is commonly seen on forced induction and diesel applications. It's expansion under high heat is minimal compared to other materials.

The price of a Custom Age 625 Plus ARP is typically much higher than say an ARP2000 because of the material, technology involved, and design and machine time. The pricing is actually very competitive to say a Nissan GT-R head stud package which has two less cylinders.

Heads do have to be romoved on some chassis models to install our head studs. (CLK might be one of them.) There is not enough room to slide the stud into the whole near the apron area.

Thanks again guys!

Weistec Engineering

Thanks for answering, James.

No wonder MBenz doesn't want to send out a TSB...200 bucks in bolts and 15 hours of tech time. Cheaper for them to deal with a couple failures

Weistec,
Do you have a set of Main and head studs for M157 Engines?