Compared to a common camshaft inside the block, PRV camshafts are definitely up top SOMEWHERE! Speaking of which: hydraulic lifters in a traditional cam in block design never need to be adjusted -- who says later engine designs are necessarily superior to earlier ones? Do not confuse the mere forward progression of time with actual progress. Hollow pushrods from hydraulic lifters also seem to do the best job of lubricating a valve train -- each valve has its own guaranteed oil supply. Bill Robertson #5939 >--- In dmcnews@xxxxxxxxxxxxxxx, "Steve Abbott" <abbotts@xxxx> wrote: > Bill > > You'll no doubt want to pelt me with rocks or something for being a > total nit-picking smart ass after this :) > Because it uses rockers the PRV is (strictly speaking) a "cam in > head" design. A true OHC should operate directly on the valves, via > bucket tappets or somesuch. > > Cheers > Steve Abbott > > --- In dmcnews@xxxxxxxxxxxxxxx, "content22207" <brobertson@xxxx> > wrote: > > One correction after re-reading the original post: > > > >PRV heads are conventional construction, albeit overhead cam rather > > than overhead valve. > > > > Bill Robertson > > #5939 > >