for the style of build you're doing
IMO, take it or leave it...
I'd do the Edelbrock E-Street Alum. cylinder heads
in either 75cc combustion chambers 'if you want more compression'
have a low compression combo
or the 84cc combustion chambers
'if you already have the desired 9.5:1-10:1 compression'
unlike some others, the Edelbrock is;
100% cast, assembled using 'Made in the USA' parts & labor
like appr. $1100-$1200 for a pair, form Jegs or Summit...
https://www.edelbrock.com/big-block-chrysler-e-street-cylinder-heads-75cc-5090.html
you can get them with specific spring & retainer combos for
the style of camshaft you have currently or choose for a latter date...
if you are inbetween in compression you can run a
thinner or thicker head gasket to make up some differences {to an extent}
with either the 75cc or 84cc, both have 2.14 in. & 1.81 ex. valves
the Edelbrock RPM or the E-Street flow better
than the Stealths std. port too
291cfm @ 0.600" gross valve lift Out of the Box, before any porting
than the Stealth's out of the box un-ported,
Stealth's out of the box are like 250cfm @ 0.600" gvl
cast in China & assembled in the USA
you can use OE style rockers & shafts if you want, same oiling system
or step up & get rollers, for an extra $$$$
just make sure you check pushrod lengths
& styles of pushrods to match your rockers etc.
there are better heads out there
IMO not really necessary for your build style, end use...
but they are 2-5 times the money also,
these E-Streets {or the RPM's}
'are really the best bang for the buck for a hot street car'
1500-5500rpm 400-500hp range,
a 40hp-70hp (or more) change, just by flow rates,
if done properly over the stock cast iron heads
or more easily, if you want to spend more $$$
hell the weight saving alone, off the nose, braking & handling etc.
IMO is worth the conversion to alum. heads
If you can't do it yourself, just have them gone thru/checked
& make sure everything is correct for your set up
you should do that with any assembled head package you buy from anyone
it's cheap insurance
Nothing wrong with the 850 QF DP, if it's tuned correctly either...
you need a hotter ignition, low ohm plug wires,
the proper, torque converter (or clutch)
& proper gearing also, to accommodate the changes too,
to get the most out of it
if $$$ or budget isn't an issue do the 'Trickflow 240' heads
for a 'really hot street bruiser' engine
