ok good deal....since your a centrifugal and not a roots type supercharger your boost is dependent on rpm... a traditional "blower cam" usually has a wide LSA (check out the "stock LS9 cam" they are designed to kill power down low because of the low end torque that roots type superchargers create...… Cam motion has a great mild centrifugal supercharger cam https://cammotion.com/camshafts/cs-2...r-centrifugal/ pair that with a good beehive like Pac's 1219 and I think you will be very happy with the results... dual springs are not necessary plus the natural tendency's of a good beehive outweigh the dual springs... I always found it weird to control a spring …. with another spring... unless you were going well past 7,500 which you shouldn't on the stock gen 3 connecting rods.... haha! beehives cam from GM originally… GM spent 8 million to develop them for LS engines... the shape of the spring lends its self to many advantages... the "beehive" shape creates a nature dampening effect it keep the spring out of resonance….. metals vibrate at different frequency's and just like glass... if you hit the correct frequency and keep it there for a bit of time.... it can break the spring like glass the Beehive shape also allows the spring retainer to be smaller at the top... and therefore saved weight by allowing a light weight retainer to be used...the steel tool metal for your valve train should work just fine... because again your running a stock bottom end.. so RPM is not necessary…. titanium is actually a harder metal than steel..its also more brittle and prone to failure... although with that said....I haven't seen too many failure on retainers,,,,,, but again you are not carrying a lot of rpm so titanium retainers aren't really necessary.. the wire its self is "ovate" meaning .. if you cut the spring and look at the profile of the wire used it is oval... this allows more spring rate but less of a chance for coil bind... when designing a proper valvetrain.... you want as much spring as needed but no more.. high spring pressure are tough on parts... they pound the valves and seats.. they can "pump down" hydraulic lifters especially stock GM lifters.... they can also cause pushrods to deflect under pressure. the rule of thumb on valvetrain stability on high RPM engines is light on the spring side of the rocker and its ok to be heavy on the pushrod side …. meaning they will use bigger diameter pushrods to control that deflection... 3/8 even 11/32 pushrods are used by LS engine builders over the stock 5/16.....so all of that to say...

1. you don't use high rpm so a simple set up of pack 1219 springs with a steel retainer(a little more seat pressure than the 1218's because boost pressure does push on the valve.) but it keeps open pressure in a nice range to keep from beating up your other parts.... 2. harden stock diameter 5/16 pushrods...again your not high rpm but the stockers are really soft just check out all the threads on LStech on how many stock pushrods have been bent with higher spring pressures... 3. since the car has 79 k new lifter trays are cheap insurance... 4. a quality hydraulic lifter like Johnson 2110's are going to keep from pumping down with your elevated spring pressure...…

I think you will be very happy with that setup its pretty much maintenance free... because while this set up is more stout than stock, it will be easier on the parts... high rpm. high lift, and high spring pressure require ALOT of maintenance especially above .650 lift. and 400lbs of seat pressure ….. springs like that need to be checked yearly or every "season" as well as wear and tear on valve seats …….valves and the rest of the valvetrain.

Sorry for the long rant haha... I used to be an engine building instructor at the Michigan institute of aviation and technology for both recip and turbine engines….. so I tend be long winded to try and educate. the day job now is building "green build" (brand new) jet engine for general electric...…
anyways let us knw what you decide on...…