Re: Intial timing setting needed, can I use the setting from the orginal engine
These crate engines are very likely fitted with full dished pistons.
Originally Posted by paw2000
What this means in a Marine application, is that your TA # becomes even more critical, since marine load ignition induced Detonation becomes more of a potential (apposed to a Q/E built sbc marine engine).
A TA of 26* BTDC @ 4k rpm appears to be a good TA (for an engine w/ this piston type), but the 4k rpm portion would appear to be high! IOW, what's it doing @ 3.5k rpm?
Are you sure that this is the correct spec?
Which ignition systems do you have? Example: EST or Mechanical Advance?
What are your limitations as to adjust TA w/out causing an issue with BASE?
NOTE: when correctly setting/checking TA, you'll want to have the harmonic balancer marked off to approx 35* BTDC.
You will then strobe this and plot this out on paper @ 1k, 1.5k, 2k, 2.5k, 3k, 3.5k and perhaps 4k rpm.
See how this jives with your correct OEM advance curve.
(yes, I'll take some crap from the Digitally Advaning Timing Light guys! )
However, this allows you to view the progressive advance in Real Time/Real Degrees.
Be sure that you DO NOT use a TA spec for a Q/E built engine if these are fitted with full dished pistons.
TA spec for a Q/E engine will usually be greater than what these can safely use.
Rick ... aka Ricardo
28' SDN F/B w/ twin Volvo Penta 5.7L DP's