add pressure to line?

Hi. I recently put in a 3 valve manifold in back yard (3/4" sched. 40 PVC used). 4th pipe (w/o valve in pic) is for 2 hose bibs added at house exterior & yard. Main water line comes in from 1" pipe reduced to 3/4" for manifold and after. PSI at hose bib nearest water line from street reads at about 30. One valve controls drip line (inline 30 psi installed after value on this line). One valve runs 5 pop ups and several short stationary heads. These 2 valves/lines seem to water fine and adequate pressure to run ok. Also 2 new hose bibs work fine. My issue is... how to add more pressure to 3rd (closest to bottom valve/line in pic) to better allow Toro 4" popups x 10 in new back yard on same line to pop up better (currently weak and delayed popping up and not all the way. Water gurgles out pretty extensive at several head locations and then after 1 min. all heads/risers raise to about 2-2.5")? I want/need them to raise the full 4" and w/o the 'soaking' at the heads (delay in coming up). Line run from manifold to first head on this line is approx. 50-60 ft. The 10 heads on this line take up another 40’ feet and 40 feet (I split line in two different directions). Admittedly I had to do some odd ‘piping’ (e.g. elbows, turns, slight variances in depth and angle of buried PVC) to get things operable. I m confident w/more pressure it will work. (I had system running and adjusted 3 heads to off manually and other 7 popped & worked fine – so a bit more pressure and al 10 should pop fine – in theory I guess. Adding heads to diff. line in this case is not an option given my pvc lay out.) Any help/suggestions would be appreciated and as detailed as possible as this is all new to me but trying to save money by doing on my own. Thx. P.S. all Toro heads, risers etc. are new and operable - so not worn or needing replacing. I check filters, made sure rubber gaskets in valve and at heads are fine. Also, (sorry lots of questions!) in addition to or in lieu of how/where in manifold to perhaps add a pressure regulator(?) is there a 'grease' or lube I can use that would likely to be helpful to apply to risers to facilitate them popping up more efficiently? (trying to find a 'cheap fix!) Is there possibly a ‘leak’ in my line somewhere or would they not work at all then? If so, short of digging up all lines, how can I locate and repair? Please advise at the earliest convenience. Thx. again.