New Design race crank, forged Nitrided, 81.33mm stroke, cross drilled, 1.625" "S" big end journal for 1275 S block with extra strong keyway and key for timing wheel.
Race crankshaft as fitted on historic and other motorsport cars.
BEWARE-you will need to make clearances on the gearbox case of 3 and early 4 synchro cases but this is a great upgrade for making smoother running engines on std engines.
The primary gear clip needs to be fettled or replaced with C-22A318.
Forged-YES forged- EN40B steel nitrided cranks are considered the ultimate in specification, even over the "billet" type. This is mainly because the grain pattern of a forging follows the shape of the webs and bearings whereas the billet type is machined across the grain. Heat treated for maximum durability, these are machined to fit mains width of the Cooper S block only.
All cranks have been re drawn to benefit from latest technology by having the larger crank webs designed to reduce whip and resistance at high revs giving smoother running and easier balancing, plus being mass centre balanced.
The bored holes for the big ends reduces weight of the crank and does not require drilling through the large counter balance C shape webs. Always check gearbox for clearance with these large webs.