Come out of thefog;Here's your recipe;
For a dual purpose machine that is more than occasionally going to hit the hiway;
5.9 roller, cleaned up heads,223/230MAXIMUM cam(050s), 8.6 Dcr,Oiling mods to live at 6800, springs to go there,HO mechanical fuel pump with 3/8 supply line, electronic ignition upgrades to support the occasional stomp to 6800.
HD-904 with semi-auto kit and 2800TC, Narrowed 8.75 with tapered bearings and 3.23s and LSD.
73 up V-8 A-body;Front K-member, UCAs, Disc fronts and 10x2" rear brakes. sway-bar,.
Relocated with the offset perches HD rear springs,1.03 T-bars,and HD shocks all around,
Minimum tire sizes of 235fronts/275rears. 295s will be better.
Optional P/S,P/B,tilt steering,frame connectors
3.23s?! Yes 3.23s will get you 60mph@6200rpm, in first, with 5% slip, a one gear run
3.55s will get you 60@6800 in first.Quite a bit out of the cams happy place.
3.73s will be 7150, just doable with the oiling mods, but you are waaaay off the peak power
If you do not care about hiway rpm,nor about ET,or Trapspeed; then consider a two-gear run to 65/70mph, and choose a smaller cam, cuz your average power during the run will be higher, and a shorter TC, cuz you are gonna have plenty of starter gear.With this combo you will not have to do the oiling mods, just try to keep the Rs down to 1000rpm over the cams peak,say 6200. And you can run this on a 5/16 fuel line, if your fuel volume test supports your horsepower level.
I suggest 4.30s minimum, and the A999. These will get you 60@5200 in second gear.This woll leave you some headroom, to redline. The starter gear is 11.78 so a stockish 2200 TC will be fine. You only need a little cam now, say between 215 and 223.This combo will make tons of torque down low, try to keep the smile off your face; people will think there's something wrong with you.You will need a traction aider. Below 60 mph the engine will not have to buck much wind, so all the power can be used to propel the vehicle, instead of using some or a lot of it to overcome wind resistance.
Use a spreadbore carb and anyold manifold (like the 71 TQ stuff).I would order a small custom cam. maybe on a 108LSA; counter-intuitive I know but;We need to shed some low-speed torque, and we need some power up top, cuz the Rs are gonna be down. This cam will run well with headers. I suggest as much lift as the heads can support and the grinder is willing to supply.
Honestly,before you hit the key, take a few breaths,mellow out. Repeat 7 times; I will not smile, I will not smile, I will not smile,I will not smile, I will not smile, I will not smile, I will not smile.
I guarantee you can't make it through first gear without smiling.
The only way to cure that, is with a smaller engine. Perhaps a 273.
The downside of course is the 3500@65 cruise rpm. I solved that with a GVOD.The Rs will drop to 2700ish.