I would not go with 1.65 rockers just to get needed open pressure .
The added acceleration rate of a 1.65 rocker may need more spring to control it then the added .040” or so of lift can provide, at least in terms of a intake valve that size.
You may be ok on the exh with a 1.65 and the added pressure, and if so then the question becomes will the added duration and lift on the exh side make you more Torque and HP, or less.
A dyno or a drag test is of course a way to tell unless someone with near the darn same motor combo as you has gone Thru the motions to find out and tell you the results .
Sometimes you can bring a motor up to 5500 rpm out of gear and with a thermal gun shoot each header tube and look for a drop in temp which would mean that the motor does not want higher ratio rockers on the exh side.
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Wernher Von Braun warned before his retirement from NASA back in 1972, that the next world war would be against the ETs!
And he was not talking about 1/8 or 1/4 mile ETs!
1) 1940s 100% silver 4 cup tea server set.
Two dry rotted 14 x 10 Micky Thompson slicks.
1) un-mailed in gift coupon from a 1972 box of corn flakes.
Two pairs of brown leather flip flops, never seen more then 2 mph.
Education is what your left with once you forget things!
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