What is the compression ratio of the engine going to be?
Iron or Aluminum Vortec heads?
Ok, since I didn't get a reply. I looked at your profile and see what you have listed for some engine specs.
(I snagged this info from another forum.)
After you have your carb and timing all set up correctly. Drive the car for a couple weeks. Then pull a plug out and see if it is light tan or dark brown. If its a light tan go one step colder. If it's tan, your good. If its dark brown go a step hotter.
Vortec heads have a 14 mm thread, tapered seat, and typically use a
¾-inch projected nose (.750) reach, small (5/8") spark plug socket.
Some suggestions:
AC/Delco
R42LTS - Stock and a good place to start.
R43LTS (colder)
R44LTS (coldest)
NGK
TR5 (stock equivalent )
TR55 (colder)
TR6 (coldest)
Autolite
103 (stock equivalent)
AR103 (Racing)
AR104 (Racing)
AP605 (Platinum)
APP605 (Double Platinum – kinda pricey)
XP605 (Xtreme Perf)
Bosch (0.69" reach)
HR9DC
HR8DPX
4305
4458
4205
Here’s a good (really complete) xref:
http://www.angelfire.com/extreme4/sk..._REFERENCE.htm
|UPDATED|10/21/2011 9:02:20 PM (AZT)|/UPDATED|
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GEN III 5.7L "LS6" Engine swap
TKO500 5 spd.
3.54 Dana 44