Timing advance, funny story

[DoubleV]

When my guy built my engine, I gave him my carb and distributor so he could run the engine on the stand. When I got the engine from him he told me to run the total timing at 35. Since I have 20* of mechanical advance that means I'd be running 15* base timing. My vacuum advance puts out 14* too and I run manifold vacuum so I should have plenty of advance at idle.

Well dispite that I've been plagued with tuning issues. Idle rougher than what it should be, power doesn't seem to be where I think it should be ( though I've only had a couple of short wot runs ), popping through the carb at wot, forced to tune the carb rich or it would run even worse when in gear, lack luster milage etc.

So just for the hell of it, I checked the timing. Perhaps it got bumped when I installed the engine? I'm out of ideas so what the hell. So I checked it with the vac advance still connected. 14* advance at idle. Uh what? Unplugged the advance and checked again. 0* timing at idle. D'oh! I think I found my problem! I assumed when the guy ran the engine on the stand he set the timing at 35 ( he even put a mark on the balancer at 35 ). He did not in fact do this and just installed the distributor at exactly TDC.

So I'm pretty happy I found the issue. This things going to be a monster now! Having more than 20* total timing at WOT is going to make things a liitle more fun I believe. :wink:

Moral of the story; don't assume your timing is set correctly. Takes just a couple of minutes to check.

 

[GuysMonteSS]

It pays to check with a timing light,I've seen people using the "time it by ear" method,and they have no frigging idea where there timing is.
Guy

 

[DoubleV]

I've seen people using the "time it by ear" method,

Those kind of guys are idiots IMO.

 

[jacobdavis1979]

The only time i time a motor by ear is if my timing light suddenly dissapears or if the motors wore out and i just dont care. That timing light is your friend lol

 

[Bonnewagon]

I agree, never *ss-ume anything. Guy with the gutless Vette I'm helping claimed the timing was "perfect". OK, as I'm staring at the missing vacuum advance hose. Lemme just check. Aftermarket chrome timing tab totally obscured the damper, so I had to use dayglo orange marker just to see the damn timing mark and set it at 12º. Found the ported vacuum (plugged) and hooked that to the vacuum advance. Grabbed the timing light and showed him the timing at idle and when I opened the throttle. Then I said to go for a ride. WOW! And he gets paid to fix cars. Sheesh.

 

[GuysMonteSS]

I've seen people using the "time it by ear" method,

Those kind of guys are idiots IMO.

I agree 100 % :!:
Guy

 

[olds307 and 403]

It takes a whole 5 mins to check timing, some people are ridiculous. I can hardly wait to see what it runs at the track.

 

[truracer20]

While you were plagued by issues did you consult with the builder? You did say he told you to run 35* total. He may run engine with his own fuel and ignition components so he doesn't have to worry about bad parts killing a new build. Actual tuning can't be done on a stand, only a dyno/load cell or in car.
Checking timing is always an automatic for me when installing an engine. Especially since I always pull the distributor in order to pre lube the engine. I do know that working with Olds engines can spoil a guy since it isn't mandatory to remove the distributor in order to pull or install them but it is good practice since it isn't hard to bend the housing. A bent housing can cause an uneven gap on the trigger and cause you to chase your tail while tuning.