Mick's 70 Lowlight

Discovered that DPR have counterweighted cranks on promotion for $US125. Now I'm debating on whether to get one. Price is so cheap it's rude not to and I guess if I'm going to try and see what I can get from a 1600 I might as well start with a fighting chance. The cam I have revs out to about 6-6.5k which is pushing the friendship a little on a stock crank as they have a tendency to flex which results in increased bearing wear if running it for extended periods. Not that it will see 6.5k too often with the new gearbox.

Emailed a few people with 1.5 ratio lifters for sale as the custom cam I've got in works with 1.4. / 1.5 lifters. My plan is to run with single HD springs. I would imagine that for 99.9% of the time I'm not going to see anywhere near 6.5k rpm so there is no need for duals, plus the lower spring pressure will help take some load off of the valve train.

Matching spring pressures is a bit of a balancing act - you want enough to avoid float at the higher rpm's but not any more. Reducing the reciprocating mass of the valve train components will allow you to reduce the needed spring pressure, as the springs will not have as much work to do. For this reason I will stick with standard aluminium push rods. Titanium valves and retainers would be nice but a little outside of the budget for this build so I'll be using stainless valves when I rebuild the heads. I'm pretty confident that with the right choice singles will work really well in this application and the stainless valves are a necessity given the head temps that a blown engine can get to.