I recently swapped to a 351W Ho in my 84 Bird. It runs excellent, but it just doesnt sound right. It sounds like it is missing out in the higher rpms. I think that maybe that the hydraulic lifters are getting worn out and losing pressure.
Now onto the questions:
1. What is required to change my hydraulic lifters over to solid lifters?
2. What else could be causing it to run like that? (valves, ignition, compression, etc)
Thank You, Robert
Lifter problems are usually most noticabe at idle(clatter). Your problem sounds more like valve float, probably due to weak valve springs...
You can't swap to solid lifters unless, the cam is changed and the heads will have to be modified to accept adustable rocker arms...