Correct timing for 351w

" I have a '80 Nautique wi

" I have a '80 Nautique with a 351w. I just converted to electronic ingnition and need to time the engine. I have advanced the timeing to where the engine runs smooth and doesn't backfire. Is there any harm to timing by feel and sound as opposed to using the timing light? Also, can an engine be damaged by running the timing too advanced? Thanks in advance. "

"Absolutely, Frank. Too advan

"Absolutely, Frank. Too advanced and you risk damaging the pistons, plugs and cylinders from pre-ignition. Too retarded and burnt exhaust valves & overheated exhaust manifolds result. Timing "by ear" is risky - use a timing light.

"

Thanks for the reply. Do you

Thanks for the reply. Do you know the correct timing numbers for the '80 351w? Thanks again.

If I recall correctly it is 1

If I recall correctly it is 10 degrees BTDC. I'll check later.

" If you have the timing advan

" If you have the timing advanced too far, then you will produce a ping, which is a state of Pre-Ignition meaning that you are applying spark before the pistion hits top dead center. You want your timing to be such that the spark arrive exactly when the piston hits TDC which is the point at which the fuel is compressed to the maximum. By applying spark at that exact time you will produce the maximum explosion in the cylendar, produce the maximum power, burn the fuel at near perfection, get the most running time for your fuel dollar, and have almost the best possible top end speed. Further advance can improve top end performance because at higher RPM's .... the time it takes for the spark to travel through your primary is the same, and your pistons are now moving faster, which is why a spark advance is built into the system.

If you are pinging your going to hear what sounds like a rattle especially when you increase throttle rapidly. This rattle is the process of those 1000's of an inch clearance on the valves, rod, main, and wrist pin bearings being slamed back together because the flow is not smooth.

I am pretty sure tha 10 degrees BTDC is the mark, going ahead with 11 or maybe 12 .... can offer just a tad of performance but you will give up just a shade of economy. 11 or 12 will not destroy your motor mind you, but at 10 you will probably get just a few more minutes out of a tank.

Go with a timing light .... and at the most deviate ..... just maybe a degree maybe two ..three is pushing it. "