Best Timing Light

[johnl]

I've got an old simple light which does not have the "advance" feature and I'm thinking I'm missing something. Then, at Kragen, where I was looking at them, they have three lights - basic with just an advance dial, next upscale with an LCD screen that shows voltage, advance, and a third that adds a dwell and RPM reading with a 4th wire that clips to the coil.

So -
(1) am I really missing anything?

(2) If so, should I get the basic "advance" light with just a dial where you set the degrees of advance, or pay more and get a LCD screen that adds voltage?

(3) The next step upscale "advance" light has the LCD display but also shows RPM and ignition dwell; I can see how it is useful to see degrees of advance at any given engine speed but in neutral with no load the cal is not going to see any of the stuff that comes with load - boost, coolant temp rise, charge air temp rise, knock, and so on and therefore I presume no significant changes in timing will be generated by the cal - right?; so is this simultaneous display of RPM/Advance feature useful? I know a dwell reading is useful when tuning a points ignition but is it meaningful with electronic ignition?

[Turbodave]

I think the basic light with the dial advance is probably fine. I've been using an old light without the advance feature for a long time and it does ok as long as your not trying to determine the total timing or anything like that.

Shouldn't be any need for the tach or dwell features on our cars.

[johnl]

Dave - by total timing, you mean when the cal adds timing just because of engine speed or when the coolant sensor is plugged in? Thanks.

[turbovanman²]

For TM's, all you really need is a basic timing light but if you going to be messing with older carb cars/trucks, then you need the advance feature. Also, the actual timing can vary between brands, I seem to remember a test years ago and Sears/Snap-On/Mac came out on top.

[johnl]

I thought of a use for it -

Suppose you want to confirm check cam timing with it - check to confirm that cam is at zero at TDC. I guess you would twist the dial back the amount of your base timing to zero and then put the light on the cam and thereby be able to see whether it is at zero or not. On an 8 valve, the light then would show whether the two big holes are on the part line or not.

Other uses?

[Mike M]

I've been a fan of using a timing light with a tach, but it isn't really needed on TMs.

You could check cam timing with a light if you clip the pickup onto the coil wire and when it fires #1 the small hole in the cam gear will be pointed at the top. No playing with advance at all. If you simply leave it on the #1 wire it will of course be ~12* off. Or you can do like me and simply check cam timing with wrench/timing marks - 2 minutes to check, 10 mins to reset a t-belt