Supercharged L67 rebuild, part two – Carnage

Part two of our rebuild of the L67 for our ‘Supermang’ VN Commodore


THIS episode of Carnage sees the work continue on the home-job rebuild of the new L67 for our VN Berlina dubbed ‘Supermang’.

Last time, Scotty was having a bunch of issues getting both the crank and rods to fit back into the L67 block with fresh bearings, with the newfound super-tight clearances causing a whole bunch of headaches.

This time around, things are looking a bit more positive, and Scotty gets to drop the crank in for the final time. It took a few sets of bearings to get the clearances right, and full credit to Top Torque, who sorted us out with some extra clearance bearings to get us out of strife.

After lots of time spent measuring, re-measuring, swearing and brow-furrowing, Scotty got the clearances he was chasing, which needed to be roughly between two- and three-thou to stop metal meeting metal in a very bad way.

The freshly machined crank from Top Torque was then slotted in with some assembly lube, and it was time to torque up the main caps with some upgraded ARP studs.

Now, normally this’d be a fairly straightforward process, but in the case of the L67, our Haynes manual stipulated that 10 – yes, 10 – steps of tightening, loosening and re-tightening had to be followed for it to be done by the book. Who would’ve thought an outdated, pushrod V6 from GM could be so damn complex to put together?

Scott simplified the process and torqued the crank up, but because we’re also having issues with rod bearing clearance, the rods aren’t going into the engine this episode.

Instead, Scotty decided to spend some time getting the ring gaps sorted so we can slap them on the pistons as soon as they’re ready. The idea was to open the gaps slightly on the new rings so they can cop a decent amount of boost.

A quick trip to Speed Pro and Scotty had a purpose-made ring filer in hand, which is much easier to use for this job than your grandpa’s old worn-out hand files.

With the rings now sorted, the rods have been sent off to Top Torque to get resized, and then we can throw them in, along with the camshaft, and finally get the bottom end of this L67 done.