|
|
|
|
Joined: Nov 2008
Posts: 408 Likes: 10
Backyard Mechanic
|
OP
Backyard Mechanic
Joined: Nov 2008
Posts: 408 Likes: 10 |
I was explaining to a friend the procedure for setting the timing on a 216 yesterday while reviewing a shop manual with him. In his case, a 1946 1/2 ton pickup, but my question is more general. He asked me where to set the octane selector after the clamp on the distributor was tightened and I gave him some guidance. He then asked me where it says that in the shop manual? After reviewing the 1941 and 1942-1948 shop manuals and a couple owners manuals I could not find any text describing the setting. My question is not what to set it at today with modern gasoline but where can I find the original Chevrolet guidance? Various Service Bulletins maybe?
|
|
|
|
|
Joined: Jan 2006
Posts: 7,046 Likes: 107
Hall Monitor ChatMaster - 7,000
|
|
Hall Monitor ChatMaster - 7,000
Joined: Jan 2006
Posts: 7,046 Likes: 107 |
VCCA Member 43216
Save a life, adopt a senior shelter pet.
1938 HB Business Coupe
1953 210 Sedan
|
|
|
|
|
Joined: Nov 2008
Posts: 408 Likes: 10
Backyard Mechanic
|
|
OP
Backyard Mechanic
Joined: Nov 2008
Posts: 408 Likes: 10 |
Tiny, I now see it in the owners manual. I would have thought there would have been a paragraph #4 in the shop manual saying the same thing. I appreciate you finding it and will pass it on to my friend. Thanks again, Mike
|
|
|
|
|
Joined: Jan 2002
Posts: 30,701 Likes: 141
ChatMaster - 25,000
|
|
ChatMaster - 25,000
Joined: Jan 2002
Posts: 30,701 Likes: 141 |
The original way no longer works with tudays high octane gas. t is impossible to get the engine to ping underload
Set octane selector to zero. Set timing as manual says. then advance the octane slector 6 to 8 drgrees advanced,. This is where you get the best overal performance......and use the lowest octane gas you can find.
A higher octane gas means the gas burns slower and nothing more.
Gene Schneider
|
|
|
|
|
Joined: Jan 2006
Posts: 7,046 Likes: 107
Hall Monitor ChatMaster - 7,000
|
|
Hall Monitor ChatMaster - 7,000
Joined: Jan 2006
Posts: 7,046 Likes: 107 |
The Octane Selector is nothing more than a conversation piece these days. Since vehicles of that era were made to run on low (by today's standards) octane fuel I don't even use a timing light. Once started and warmed up I set the timing to the fastest/smoothest idle then lock it down with the OS on 0. If necessary I can retard it a degree or two using the Octane Selector. It hasn't been necessary yet.
VCCA Member 43216
Save a life, adopt a senior shelter pet.
1938 HB Business Coupe
1953 210 Sedan
|
|
1 member likes this:
Clement |
|
|
|
|
Joined: Dec 2007
Posts: 4,024 Likes: 99
ChatMaster - 4,000
|
|
ChatMaster - 4,000
Joined: Dec 2007
Posts: 4,024 Likes: 99 |
I agree that the octane selector is just an interesting relic of a bygone era.
I also agree with Gene that it is almost impossible to make one of these classic engines knock under under load. due to highly advanced timing.
The limitation I determined was that with any more than about 13 degrees BTDC static timing the engine was hard to start due to "kick-back". This was especially noticeable when it was at operating temperature.
Rusty
VCCA #44680
|
|
|
|
|
Joined: Jan 2002
Posts: 30,701 Likes: 141
ChatMaster - 25,000
|
|
ChatMaster - 25,000
Joined: Jan 2002
Posts: 30,701 Likes: 141 |
Years ago the octane selector allowed the owner to set the timing (advance or retaed) the tiing for the best performance for the gas he wa using due to the fact the octane varied from brand to brand Also we had no way of knowing what the actual octane was .
Gene Schneider
|
|
|
|
|
Joined: Nov 2008
Posts: 408 Likes: 10
Backyard Mechanic
|
|
OP
Backyard Mechanic
Joined: Nov 2008
Posts: 408 Likes: 10 |
Thanks for everyone’s feedback. When my friend asked me what did Chevrolet recommend at the time I was at a loss to find it. Mike
|
|
|
|
|
|
|
