part 2
crank. there are several options for a crank, many people spring for a chance of more cubes the most popular is a 347, the two most popular are from eagle and scat, i have used a scat crank and an eagle the main journal size is a bit on the tight side for bearing clearence and will probably require a polish you will know if you measure the installed bearings and mic the crank. the surface finish is not good on some eagle cranks. the same thing with the rods, check check and check again. above .002 and below .003 provided you have done your due diligence on the oiling system with a polished crank. then put the crank in and plastigauge. now turn the crank 180 deg. and check again if the middle bearings go tight the crank is not straight, some people can straighten a crank with a hammer enough to get by, likewise if the end bearings go tight. look at the radii of the journals and ensure that the bearing will not touch the radii and that there is a smooth transition from journal to web now check end float, stick cars tend to wear a crank due to the clutch being held dow at traffic lights add some light oil to the crank and see if you can spin it when torqued up, i don't mean turn it, spin it
i must add here that i bevel the corners of the main caps and block to reduce stress risers and likewise the bearings should be deburred with a small file on the mating edges and drilled for better oil flow.
if you are using the original cap bolts, try a die nut down them to see if the thread is deformed, if the die picks up thread throw them away. if you are using studs screw them in hand tight then back them off half a turn
end of part 2
_________________ this story shall the good man teach his son, and chrispin chrispian shall ne'er go by, from this day to the end of the world. but we in it shall be remembered.
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