2023 ARP Catalog

36 Head Fastener Measurement Sheet The illustration below shows the variables that come into play when determining the proper fastener for a particular application. Some cylinder heads have different column heights and additional variables come into play when using aftermarket engine blocks. It is therefore critical that you determine exactly how many different bolt/hole combinations exist for the cylinder head installation. Cylinder Head Engine Block Head Counterbore Depth ARP Head Stud Measurement Sheet - rev 07/2019 RECOMMENDED TOOLS 1) a properly calibrated caliper that will measure internal and external diameters, as well as depth 2) Some modern heads have recessed spot faces and may require extended tip internal calipers for B and D 3) an SAE or metric thread gage HINTS At least one head should be removed from the engine and placed on a flat surface Repeat to ensure accurate measurements All holes should be checked to determine if all are the same Use separate copies of this sheet as needed List all inch measurements to 3 decimal places (X XXX) and all mm measurements to 1 decimal place (YYY Y) Take a photo of completed form and attach to this email of fax completed form to 805 650 0742 Name_ ___________________________________________ Email_ ___________________________________________ Phone/Fax_________________________________________ Date_ _________________ ARP Question #_ _____________ Engine Specs_______________________________________ Block Mfr./Model_ ___________________________________ Year_ ________ ❏ cast iron ❏ aluminum Head Mfr./Model_____________________________________ Year_ ________ ❏ cast iron ❏ aluminum Stud/Bolt Hole Diameter Head Gasket Thickness Stud/Bolt Hole Depth Thread Start Depth Thread Size & Pitch Calculated Thread Length Block Hole Depth from deck to bottom of hole Thread Stop Depth Head Counterbore/Spot Face Width C A B D E F G H I J use an internal or extended tip internal calipers measure the thickness of the gasket from deck to bottom of threads - use the depth bar to extend to the bottom of the threads clean any debris from bottom of hole, use the depth rod to extend to the bottom of the hole, take several measurements use an SAE or metric thread gauge on the bolt threads if you do not have extended thread gauges subtract F from G from deck to start of threads - use the depth rod to measure to the top of threads from bottom of counterbore to bottom of head - use depth gauge with head on a flat, solid surface use depth gauge Sheet _____ of _____ for this engine Holes with these dims _____ Total Hole Count _____ Original Bolt Info optional Underhead Length Head Height Collar Diameter Are there any clearance issues around the bolt head? (use another sheet to explain or sketch) FASTENER TECH