PDA

View Full Version : IGNITION TIMING HELP



INFINITEJJ
06-17-2001, 02:42 PM
I know that it's been talked about before,But please bear with me. I have a stock 460 ford in a 19' jet that turns around 4600 rpm. I've had it for over a year and never checked the timing until today. At idle it has 22 degrees advance and at 3000 rpm it has 46 degrees advance. These numbers seem a little extreme to me? The boat has always started right up and ran ran good, the idle might be a little rough but not too rough. So here are the questions.
1- At how many rpm's should I set timing at?
2- What should the timing be set at?
3- What is too much or too little?
Thanks for your help. JON

84Keaton
06-17-2001, 07:36 PM
Jon,
Factory specs for the Berkeley 460 Pack-A-Jet timing are 10' BTDC at 850 rpm idle and 40' total advance. I recently suspected false timing readings on my stock 460 and noticed that the harmonic balancer had slipped by about 18 degrees! Thus, an indicated 10' advance at idle was actually 28 degrees. Makes starting the engine a bit tough! Check the orientation of the timing marks relative to the keyway on your balancer against those of a brand new one. The rubber press fitting holding the inner and outer halves together can deteriorate, causing the slippage and could be disasterous if the two came apart at high rpm. Good luck.

froggystyle
06-17-2001, 07:38 PM
Seen that happen on my Uncle's 21' Eliminator with BBC. Nearly made my dad a soprano while he was stradling the engine timing it.

spectras only
06-17-2001, 09:09 PM
Infinitejj, 460 Fords by Harman or Hardin marine had a tag on the bellhousing stating 10 degrees adv at idle,but ignore that and set your timing max 36 degrees at 3000RPM. I never had a harmonic balancer coming apart or slip on a boat,except my 1980 Corvette with only 30000miles on it. Check for demage on the damper,if it's oil saturated or dried out[the isolator]if your engine is a 70's or 80's vintage.

INFINITEJJ
06-19-2001, 04:40 AM
Thanks for the help guys, I thought 46 degrees was a little radical. One more question. At 3000 rpm should the centrifical advance be maxed out?
[This message has been edited by INFINITEJJ (edited June 19, 2001).]