H13 Tool Steel Head Stud Kit – Lamspeed Street Series – GR Yaris G16E-GTS Lamspeed

Lamspeed Cylinder Head Stud Kit – H13 Tool Steel – For the GR Yaris G16E-GTS Engine

For applications where you have turned the boost right up over 30psi and plan to keep the head from lifting. This is the first thing that occurs from testing when pushing the limits when Lamspeed set the World Drag Record in a GR Yaris running a 10.5 @ 131mph to then setting the GR Yaris record around Sydney Motorsport Park at the 2022 World Time Attack Challenge with a 1.36.8

Lamspeed are the first to develop and put into production an aftermarket head stud solution by taking their own measurements to ensure the studs are of the correct length so that they bottom out on the block, the factory bolts do not.

These H13 tool steel head studs are manufactured specifically for Lamspeed and are much stronger than the typical 8740 chromoly.

Conventional washers are only 23-24mm OD, whereas our new oversize washers are designed to encompass the entire head bolt boss. CNC machined from 4140 chrome moly bar stock, hardened to HRC 45 and blackened for appearance.

With the Street Series they have not included the hex broach to reduce cost and will suit majority of the market. This means you will need to either thread them in by hand or double nut them to thread them into the block.

What makes Lamspeed’s head studs better than the competition?

• The dogpoint feature seats the stud in the block and preloads the fastener for a more accurate and repeatable torque sequence. We also include the ARP ultra torque assembly lube with each set. When it comes to head stud performance properly torqueing the studs is paramount and we have made every effort to ensure torque precision and repeatability.
• Direct OEM replacement, no modifications.

What is H13 Tool Steel?

• 25% more clamping force than typical ARP 8740 head studs.
• H13 is a Hot work tool steel with 5% chromium. Its high impact strength protects against cracking and is easy to machine. This steel is designed to retain hardness at elevated temperatures and withstand the effects of alternate heating cooling.
• This material type will suit most customers looking for extra reliability on builds up to around 600bhp