Using TF 270 heads on a 470 build. HS 70015KE rockers-all good. Engine was built last winter after following a lot of Andy F reads. Spot on, thanks Andy. removed heads from box, checked valve seats and put back together. did install different springs to accommodate cam-280/655 roller. Push rods were measured for exact length needed. ARP stud kit for TF heads and rocker arms. Summit Valve covers-perfect fit. Put in car 3 weeks ago, got some 20+ hits on it, now tuning can begin. No dyno test, just track tuning. so far it appears to be at 750 range. They work nice.