Timing Light

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John Vardanian
Posts: 1906
Joined: Wed Sep 04, 2002 12:13 am
Location: San Francisco Area

Timing Light

Post by John Vardanian »

I have been using a 1970's Sun light for timing and now am wondering if a new digital type with adjustments would make me do a better job of it. Do these help you with a more spot-on setting, or is it like the old saying that glasses don't make you any smarter? Thanks for your advice.

john
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Jimmyr
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Location: Scottsdale, AZ

Re: Timing Light

Post by Jimmyr »

John, yes they are better and brighter, knowing that we must view the marks thru a small hole in the bell housing it helps. Also, if you can only see the one TDC mark, the adjustable ability on the new lights make it easier to know the advance degrees without seeing any other marks. Jim
John Vardanian
Posts: 1906
Joined: Wed Sep 04, 2002 12:13 am
Location: San Francisco Area

Re: Timing Light

Post by John Vardanian »

Thanks Jim. With the old gun I get the revs up to 5000 and line up the pointer as best I can with the markers on the flywheel. Will the digital light tell you if what you see is spot on or a degree or two off, etc? What is the purpose of the up/down button (or the turn knob) on the gun?

john
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Jumprun
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Re: Timing Light

Post by Jumprun »

Asking what timing light is best is almost as controversial asking what kind of oil to use, but the following is my experience.

I used to use the dial type (craftsman) which allows you to adjust the dial to retard the flash so you only need to see the TDC mark to check the desired spark event. I bought this Craftsman late 70's but it got damaged so I replaced it with another one in the 90's which was total crap, it was cheaply made and the dial back feature was inaccurate. I lost confidence in it so I bought a very simple Snap-On that works on a "D" cell battery so it requires no hooking up leads to the battery. It has no dial or adjustments setting, it has very little to go wrong, of course this means you must mark the flywheel at the desired advance with bright paint.

The Ferrari 330 flywheel is nice because it has idle and final advance marks so to avoid confusion I applied white paint to "PM1/6" (TDC) and yellow to the spark event lines. I also used the ring gear teeth as a reference because the 330 flywheel has 100 teeth, each tooth can be used as a reference of 3.6 degrees.

The 330 Ferrari flywheel is very generous with flywheel marks, providing for both valve events and spark events, for both cylinder banks. At first all these lines and marks were confusing and slowed me down, but I came to appreciate them when I needed to move my cam timing.

Here's a tip to mitigate the shitty access and viewing angle of the flywheel viewing hole. I rigged up a stiff piece of sheet metal as a pointer for the crankshaft pulley and carefully transferred the flywheel marks to the pulley/harmonic balancer, this way I could rough-in my adjustments without having to break my back to peer into the little hole so many times. Of course my final adjustment are made by directly using the flywheel marks.

Someday I might go back to an adjustable light but I keep forgetting because my simple one works fine.
John Vardanian
Posts: 1906
Joined: Wed Sep 04, 2002 12:13 am
Location: San Francisco Area

Re: Timing Light

Post by John Vardanian »

I broke down and got a new digital light, even though my 1960's light was serving me just fine. I hooked it up today with high hopes and everything seem to be working fine until I went for the high RPM set. When the revs went above about 3800 the light turn off and stay off until I dropped the revs. Could it be that the no-resistor plugs are interfering with it? Does anyone have one of these or similar experience with these type of lights? Thanks.

https://www.innova.com/en-US/Product/De ... 2939300942

john
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Steve Meltzer
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Re: Timing Light

Post by Steve Meltzer »

I started with a basic timing light, but once i got a "dial back" analog Craftsman unit it was like night and day...a great, great feature. But most recently I bought an Innova #3568 on eBay for about $70 included shipping, and it's the cat's meow. (and I should know since we have 6 cats!!) The digital read, dial back feature and seeming accuracy is just excellent and having that digital tachometer beats my old swinging needle analog type...much easier to tell smaller differences. Also good is its detachable cord, so easier to do the timing when the timing marks are under the car. (like a Daytona or Ghibli). Have not used the light at the high RPMs John V was questioning, so no help on that one. I'd query the manufacturer on that one. Doesn't seem right to me. s
steve meltzer,
"I've spent all of my money on wine, a beautiful woman, and stunning cars. Then, squandered the rest."
John Vardanian
Posts: 1906
Joined: Wed Sep 04, 2002 12:13 am
Location: San Francisco Area

Re: Timing Light

Post by John Vardanian »

Steve, you might try it at full advance to see if it will still work. I Googled my issue. It took me to a Corvette forum where two people had the same problem with the same brand/model of light. So, there must be something with these lights. I called the manufacturer the next day and they told me to box it up and leave at the door. I am back to my trusty old Sun light.

john
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Steve Meltzer
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Re: Timing Light

Post by Steve Meltzer »

if i can remember, which is very questionable, i'll check it this week and report back. thanx. s
steve meltzer,
"I've spent all of my money on wine, a beautiful woman, and stunning cars. Then, squandered the rest."
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