Reply
 
Thread Tools Search this Thread Display Modes
 
Old 10-05-2010, 09:38 PM   #1
3 Rivet Member
 
gmehal's Avatar
 
1965 30' Sovereign
1975 26' Argosy 26
beaverton , Oregon
Join Date: Feb 2008
Posts: 169
Setting timing on the 454 using vacuum gauge

Has anybody done this? if so what was your reading? Mine started at 15 and I raised it to 20. It went a little higher but I backed off a bit. Seems to run great but curious about others numbers.
__________________

__________________
1965 31ft Airstream Sovereign
1975 26ft Argosy Motorhome

Imagine the sight of them linked together!

gmehal is offline   Reply With Quote
Old 10-05-2010, 10:02 PM   #2
tpi
Rivet Master
 
2005 25' Safari
Trabuco Canyon , California
Join Date: Apr 2006
Posts: 866
Images: 2
I strongly don't recommend setting timing using vacuum.

This is likely to lead to excessive advance. When the engine is idling typically the vacuum advance is offline for emissions reasons. The engine would typically like much more advance at idle than the factory sets up. However off idle, the vacuum advance kicks in and the centrifugal advance adds more with additional engine speed. With this additional advance, any timing set by vacuum would quickly lead to too much spark advance.

Use a timing light and set to factory spec. Confirm centrifugal and vacuum advance are working properly. You may be able to go a couple degrees on either side of the spec for specific conditions, but always listen for pinging/detonation which indicates too much spark advance.
__________________

__________________
tpi is offline   Reply With Quote
Old 06-24-2012, 04:33 PM   #3
2 Rivet Member
 
1977 28' Argosy 28
dexter , New York
Join Date: May 2012
Posts: 46
vacuum works as a way to set timing on an older motor 20 in. is a little high , this is from memory 15-18 in. is the green aera of the gauge Iuse a light and a gauge because you need the gauge to set carb after timing ,the light will check advance cent.and vac. and 2degrees advance is better with the gas today.hope its helpful,
__________________
jonesy 1 is offline   Reply With Quote
Old 06-24-2012, 06:39 PM   #4
Rivet Master
 
1982 28' Airstream 280
Redwood City , California
Join Date: Mar 2008
Posts: 1,735
Well what ever anyone thinks, you can't properly set the timing via vacuum nor by feel. Proper instrumentation is your best friend. Besides, why would you not want to use a timing light...basic timing lights are cheap!

I set my '81 454 at 4 degrees advance for smog testing. I haven't changed it and there was no audible pinging on my last 1000 mile trip mostly over mountain between California and Oregon with many 6% grades lasting 8 to 10 miles each.

I would like to do some experimenting with the advance curve and jetting on the Quadra-crap, but I certainly wouldn't do this with out using a timing light. Now, my other issue is that I can't find any information nor anyone that knows how for a non-race car 454...sad!
__________________
http://projectupdraft.com/airstream

"We are free to go where we wish and to be what we are"
Richard Bach, Jonathan Livingston Seagall
dadstoy is offline   Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
454 Chevy timing Tom & Janet Salhus Mechanics Corner - Engines, Transmission & More... 40 11-20-2013 08:12 PM
454 engine timing joe gooch Classic Motorhomes 3 09-22-2010 12:17 PM
Setting up Victorialhq On The Road... 3 11-22-2009 02:07 PM
Need help with forum setting... Safari Tim Forum Admin, News and Member Account Info 4 07-07-2004 07:55 AM
Alignment setting Jim Foster Axles 5 06-10-2004 02:36 PM


Virginia Campgrounds

Reviews provided by




Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 01:19 PM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.

Airstream is a registered trademark of Airstream Inc. All rights reserved. Airstream trademark used under license to Social Knowledge LLC.