[Anton]

I'm unsure what to set my ignition timing at on my 305 (early 80s), it has an edelbrock 1406 carb, 2101 performer intake and performer cam (summit but equilivant) and factory HEI dist,. I searched and cant find any information on factory timing specs.

I currently have it set at 14* BTDC base with the vacuum advance disconnected.. Cruising down the highway i can hear a ticking sound coming from the engine, is this pinging?

Looking for reccomendations for what to set it at for best fuel economy (factory specs im assuming?).

Also, should I be able to crank the engine over by hand with all the valves fully closed (pushrods removed)? I did this while changing my cam and could hear the air bleeding out.

thanks

[97Z28]

try dropping the timing to around 10 - 12*. and make sure you hook the vacuum advance back up. then test drive it and see if that helps.

were the spark plugs in the heads? if they were then you may have blowby issues. i'd do a compression test and leakdown test and see what you come up with. you will hear a certain amount of air rushing past. but it shouldnt be so easy to turn by hand.

hope this helped!

-Matt

[docvette]

Doc here,

Early 80's 305, with CCC or CCCC Computer (or not), 8 Degrees static . Hook the advance unit back up , Manifold source for power, ported source for economy and smog..

Detonation sounds like marbles being shaken in a can..occurs usually under throttle load, and uphill pulls..Being that far advanced will probably make it run a bit hotter than normal.

After you set it for 8 degrees , take it on to the freeway, going up the ramp..Hammer it..If it pings / Rattles.. retard it. If it barks like a dog, advance it a bit..

Don't know what to tell ya about turning the engine over by hand with no valve action..but that doesn't sound right..maybe with a socket and breaker bar..Do a Vacuum Check .. 17 to 21 In Hg and STEADY, Bouncing Rapid Needle indicates burned/Leaky Valves, Guides, or seals..

Do a Compression, 125 to 150 PSI + / - 10% all the way around is good..much lower think rings/ rebuild.

Did you break in the cam properly ? 2000 RPM for 5 to 20 minutes?

Doc