| [GMCnet] 403 and 455 Good power plants [message #204600] |
Sun, 14 April 2013 00:20  |
BobDunahugh
Messages: 2465
Registered: October 2010
Location: Cedar Rapids, IA
Karma:
|
Senior Member |
|
|
Both power plants are good units. I personally like shorter stroked engines. As I have said before. What makes the 455, and the 403 come to life is Jim K's 3:70, and 4:11 final drives when your pulling a load or not. The 3.21 is a help. I pull my enclosed car hauler with one of my Yenko Stinger to road course track events each summer. My gross is in the 19,000 to 22,000 lbs range. My 403 that's in our 78 Royale performs fine. I have absolutely no extra cooling modifications at all. On steep grades. I'll run it up to 4,500 RPM's, and leave it there. One of my Chevy Yenko Stingers has an idle of 2,200 RPMs. I run 3 of my 4 Stingers in the 6 to 8,000 RPM range all the time. My 403 runs so sweet above 3,000. Love it. Bottom line. Leave in your coach, what ever it came with. And enjoy. But DO change your final drive. Changing your chain ratio in your trans. DOES NOT take ANY load off the trans. Pure Physics. Bob Dunahugh.
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
|
|
|
|
GMCforum
Search
Help
Register
Login
Home
