GMCforum
For enthusiast of the Classic GMC Motorhome built from 1973 to 1978. A web-based mirror of the GMCnet mailing list.

Home » Public Forums » GMCnet » Fuel
Fuel [message #302614] Sat, 25 June 2016 17:27 Go to previous message
jor is currently offline  jor   United States
Messages: 43
Registered: June 2016
Location: Tucson
Karma:
Member

1. OCTANE: I'm reading the manual and it indicates that the 455 uses "87 average octane." I was advised by the PO to run 91 (rebuilt engine with 5,000 miles). What is the consensus here on appropriate octane for a stock 455 with stock ignition timing?

2. TANKS: I was under the impression that the GMC has two 25 gallon fuel tanks but the manual states, "...auxiliary tank normally contains seven to nine gallons." Not sure what that means. Also, I was told that fuel is drawn from tanks and that it is not necessary to switch from one to the other with the fuel tanks rocker switch on the dash. Is that the case?
Thanks.
jor


John O'Reilly 76 Eleganza II (quad bags, disc brakes w/ reaction arm. 3.70 gears, manny trans, headers, Patterson dist.) Tucson, AZ
 
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Previous Topic: [GMCnet] 7000 mile report
Next Topic: Lug Nut Torque
Goto Forum:
  


Current Time: Mon Nov 18 03:39:52 CST 2024

Total time taken to generate the page: 0.01828 seconds