This is the short head bolt (1-15/16" long) for 1916-1928 Chevrolet cars & trucks. See also AF-215 for a full set of both long and short bolts.
CAUTION: these are the original 1/2"-12 bolt thread (NOT 1/2-13). This thread is a British standard thread and NOT the same as USA. It is not a common bolt. BEFORE INSTALLATION, IT IS ABSOLUTELY NECESSARY TO CLEAN THE THREADS IN THE BLOCK WITH A PROPER 1/2-12 TAP. Order FS-360 Tap for 1/2"-12 thread to clean block threads.
AF-215 SET INCLUDES:
4 EACH 1/2"-12 X 5-3/16" LONG HEAD BOLTS;
4 EACH 1/2"-12 X 1-15/16" SHORT HEAD BOLTS.
TORQUE SPECIFICATIONS FOR EARLY VEHICLES
Prior to the late 1940ís there were no torque specifications.
When working on early cars & trucks there is nothing in the shop manual to show you how much to tighten down vital components such as head bolts, main bearing bolts, flywheel bolts, etc.
Years ago we found a universal chart of TorqueValues.
This chart shows torque values in foot pounds based upon the type of bolt and the diameter of the bolt.
It has been extremely helpful when working on vehicles prior to 1949.
Of course, it is recommended that bolt threads be cleaned with a wire brush and oiled before being torqued (do not oil wheel lug bolts).
Running a tap to clean out the bore is also recommended along with a good blast of compressed air for final cleaning.
Add a few drops of oil and you will be ready to torque your bolts.
"Technically there is a difference between the torque given to a fine thread bolt and that given to a coarse thread bolt.
But taking the entire chart shown here, the variation will not exceed 1%.
So for increased convenience the chart has been simplified and practical shop values given.
Actually automobile manufacturers give a tolerance.
For example, when 75 foot pounds is desired, the value will be given as, perhaps, 70-80 foot pounds.
And this is so much more accurate than even the most skilled mechanic can manage with the old rod type torque wrench."
Original bolts on early Chevys are plain steel ñ no hardened bolts or alloys.
For your old Chevy, use ONLY the plain steel torque value.
TORQUE VALUES for Fine or Coarse Thread Bolts
(Torque figures are in foot pounds)
Bolt Diameter Plain
When bolts are torqued, it stretches the bolt. Occasionally the original bolts need to be replaced.
We offer new head bolts for 1916-1928 Chevy 4-Cylinder engines and also 1929-1932 Chevy 6-Cylinder engines.
This part fits most 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926 1927 1928 Chevrolet Cars; exceptions may apply. Please read the complete description to see if this part fits your specific vehicle and application.
This product can expose you to a chemical, which is known to the State of California to cause cancer or reproductive harm.
For more information go to www.P65Warnings.ca.gov