Cvh ticking, sounding like a scooby
I have recently built a cvh 1.9efi and has run ok for few hundred miles so far. However it started to make a noise like a lifter had failed, ticking, got louder and more repetitive with revs and engine sounded rough. Running round town at low speeds not to bad, get on motorway at 70 and after 10 Minster allmity noise as if no oil to top end. Stop engine, leave a few minutes restart and ok until you get up to speed again. So changed lifters and seemed ok for 300 miles but has started again. Checked oil pressure tonight and fine at nearly 60 psi around 3000rpm. Checked cam lifts and whilst not to book figures its not too bad. Piut in an old set of lifters and still the same. Beginning to think it's bad luck coming to haunt me and could be broken piston ring.
Anyone got a view on where to look, what to try?
Dave