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- Nov 26, 2009
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I first started using triangular waisted head studs around 2010. Since then people have been asking for them so I decided to make them available for Maney cylinders. The triangular stud is the way to have a reduced shank stud that will stretch (instead of pulling out threads) yet still have 3 points that are a full 3/8" diameter so the head locates correctly on the cylinders. The photo below shows long 3/8" triangular high strength head studs for use with Maney cylinders (no one else makes these). 5/16” twin fluted waisted high strength studs are provided for the US threads near the pushrod tunnels. ARP high strength 12 pt nuts and Belleville spring washers.
The studs above need timserts - see instructional video here:
youtu.be/F0RnqPuT4VA
The photo below shows what can happen with regular non-waisted bolts that don't stretch. This motor stayed together for so many races that the cylinder through bolts loosened, the cylinders vibrated up and down and broke the bolts. Using bolts that stretch instead of loosening helps prevent this.
The solution for breaking cylinder through bolts is waisted shank bolts that can stretch. These ARP bolts are machined lengthwise to prevent stress risers. Since they are not used to locate they can be twin fluted instead of triangular to save machining costs.
For Maney cylinders you need head bolts with US threads. These are APP high strength head bolts with stretchable twin flute shanks. The stretch helps keep the studs tight throughout the aluminum expansion range and that in turn helps prevent head gasket oil leakage.
For Heads with stock iron cylinders there are high strength triangulated studs at the required shorter length (with ARP 12 pt nuts and Belleville spring washers and long SS nuts).
The studs above need timserts - see instructional video here:
youtu.be/F0RnqPuT4VA
The photo below shows what can happen with regular non-waisted bolts that don't stretch. This motor stayed together for so many races that the cylinder through bolts loosened, the cylinders vibrated up and down and broke the bolts. Using bolts that stretch instead of loosening helps prevent this.
The solution for breaking cylinder through bolts is waisted shank bolts that can stretch. These ARP bolts are machined lengthwise to prevent stress risers. Since they are not used to locate they can be twin fluted instead of triangular to save machining costs.
For Maney cylinders you need head bolts with US threads. These are APP high strength head bolts with stretchable twin flute shanks. The stretch helps keep the studs tight throughout the aluminum expansion range and that in turn helps prevent head gasket oil leakage.
For Heads with stock iron cylinders there are high strength triangulated studs at the required shorter length (with ARP 12 pt nuts and Belleville spring washers and long SS nuts).
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