factory L-banger.(were sold factory just not with the twincam head)
was faster than the gtrs and z cars too.
the LZ twin cam survived in racing into the 80's (touring cars, formula atlantic, even WRC. check out the 600hp tomica R30 skyline jtgc car no FJ's there!!)
PB series are cool i'd love to own one.(or put the front on a ute)