We are seeing upper 90`s to low 100`s here now . I see about 190 at a stoplight and it drops to 180 to just under 190 when moving . I`ve got a Ponds 482 engine . I`m surprised your timing is that low .... my engine wants and needs 38 degrees for a max and about 20 degrees when idling ( 800 to 900 rpm ) . When I retarded my timing , it ran slightly hotter .... but then everyone`s engine and location is different .
The location of those two coolers may be dirtying up the air through the radiator .... try a smoke test and see how the airflow is . I have nothing in front of my radiator .
On my race car some years ago , we ran a consistent 200 degrees and
oil as high as 230 degrees . One of my friends who is involved with NASCAR said his team ran some tests and found best power and life with a water temp of 195 to 200 and
oil temp about 200 to 210 degrees ... but that was for their specific engine combination . They also wouldn`t hesitate to run 210 degrees on water during a race .... and they ran water ... NOT
antifreeze/water mixture .