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Tested a couple timing lights today...

22096 Views 22 Replies 18 Participants Last post by  Highway Star, 
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After hours of searching on timing light accuracy, msd box scatter, dial back light issues, timing light brands etc....I decided to test out a couple today.

The baseline:

1)My car is running locked out timing(no vacuum or centrifugal advance) so its really simple to check.

2)The timing light I have always used is a Sunpro(Actron #7519) dial back style. I have had this thing 15yrs and its always worked well, but the reason I was questioning this is now my car has a MSD 6AL and everyone says the dial back lights are not accurate, especially on a MSD ignitions. I really had no idea where I was at. On the dyno, we set the timing at 31* with a Snap On digital light. Upon installation in the car after stabbing the distributor, I set the timing at 32* with my Sunpro light and thats where I have been running it.


So today I go to Sears to buy a Craftsman non advance light, only to find out they are not selling them anymore...All they had was a Craftsman dial back style and the Craftsman Professional series (digital) with the tach and other stuff. Well since I already have a regular dial back, I decided to roll the dice on the digital model.


My balancer is already degreed so I figured the standard style light would be easy to test against the dial back method but....since I couldnt find the non dial back light, I will just have to hope the dial back method is accurate.

I came home tested both at idle, 1500 rpms and at 3000 rpms(since MSDs are supposed to only fire single sparks after 3000).

Both lights read IDENTICAL at all engine speeds and degrees.....Both light lights had about the same about of reading fluctionation at idle(I attribute this to the MSD multiple sparks but this was minimal) at 1500 rpms, both lights were reading the same smoothness at "0"(using the dial back set at 33*) and at 3000rpms, the line was rock steady at "0".

So for me, I consider two timing lights that are reading IDENTICAL to be pretty accurate, eventhough neither one I am supposed to be using due to their dial back feature and the MSD interference. I will say the digital light is pretty bad ass, the strobe is much brighter then the old Sunpro light and the digital action makes it idiot proof to add a degree or two with great accuracy. Lastly the tach feature is nice when you are laying over the fan revving the piss out of the motor thinking your are "up there pretty good" only to find out you are at 2k or less....LOL

I will keep both and continue to benchmark them against each other but, I guess this is close enough for me. As long as they are consistant, the absolute numbers shouldn't normally matter TOO much, but my motor is on the edge of detonation so I need to keep the timing in check at all times.

Sorry for the long post, just thought I would throw my experience out there.
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A
Alan have you considered trying MSD 8680 timing control. I tried to get the link but it was taking awhile loading.
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S
aukai said:
Alan have you considered trying MSD 8680 timing control. I tried to get the link but it was taking awhile loading.
Click to expand...
No I am not familar with it honestly. Currently I keep the timing conservative(31-32* on pump gas and 33* on a 12% VP110 mix). I am just running the MSD 6Al with the Pro billet distributor and Blaster II coil. An adjustable knob style controller would be nice to pull a couple degrees out of it on the fly for when I am on straight pump gas and don't have my light with me. Not sure I would trust them though.
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A
I'm going to have to at 11.5:1:D
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W
Whats that digital craftsman unit run? I have an older craftsman timing light but its been dropped a few times :) and I am starting to suspect its accuracy.
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Jebchevelle
my actron looks just like that snapon one only chrome lol works great never had a problem with it it matches the marks on my balancer dead on.
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davewho1
webfoot said:
Whats that digital craftsman unit run? I have an older craftsman timing light but its been dropped a few times :) and I am starting to suspect its accuracy.
Click to expand...
http://www.sears.com/shc/s/p_10153_12605_00914066000P?keyword=automotive+timing+light

;)
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Jebchevelle
I paid half that for my actron at advance auto.
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M
Thanks for posting your findings. These are the posts I like to see. Thanks again.
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B
Jebchevelle said:
I paid half that for my actron at advance auto.
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I have tried one of those and they wouldn't work. Maybe I had a bad one, but it didn't work worth $.02 for me. Would cut in and out all the time as rpms were brought up.
Using a craftsman manual dial back for quite a while now with good luck.
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G
I bought a conventional Craftsman Timing light about 3 months ago. Basic unit (no dial back). Accurate, simple.
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B
I have an OLD Sears Craftsman dial back timing light that is EXACTLY like the Sunpro model pictured above.
I found it to be very accurate with running locked timing, a MSD crank trigger and MSD 6AL box.
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H
This is a neat thread. Thanks for posting, it is a good topic, and well presented.

To add my $0.02, my buddy has an analog dial back chrome craftsman light. I have a harbor freight $15 special...

Mine timed my car at 19° initial/36° total and his timed it at 18° initial/35° total. I guess mine is pretty close. I at least know that I'm within a degree or two of accurate.
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F
whats a timing light, i use the laptop to set mine, lol
years ago, a mag. did a test, they found the old Sears dial back to be one of the best-not sure who makes it, prob a lot come from the same place, just built to diff specs-of course, its only as good as the timing marks on the balancer/pointer
i did add a pointer on my LS engine, dialed in at true TDC, used the timing light to cross ref the computer, they read the same, verified the boost retard, so i assume the old Sears is accurate
i use an MSD 6010 to fire my engine, one thing i noticed , which follows along with the MSD only single firing above 3K, when i put the inductive clamp on the plug wire, and look at my laptop, i notice the dial with the timing jumps all over the place (the view on the laptop can have 3 large dials, RPM, timing, and i forget the other) untill 3K, which seems to prove out that theory maybe, not sure what the timing light is actually doing to the timing graph, but must be related to spark scatter
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S
BillsCamino said:
I have an OLD Sears Craftsman dial back timing light that is EXACTLY like the Sunpro model pictured above.
I found it to be very accurate with running locked timing, a MSD crank trigger and MSD 6AL box.
Click to expand...

Yeah I noticed that.... I am thinking Actron used to make the old steel/chrome timing lights for everyone....(Sunpro, Sears etc)...


I had never questioned the accuracy of my old Sunpro, never crossed my mind that they could be anything but accurate... After searching here at TC and some of the other boards, I became concerned about the accuracy with the MSD ignition. But since my new Sears digital light and Sunpro read identical...(I mean 33* and 33*) I am gonna save myself some stress and assume they are accurate and move on...:beers:
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7
i bought an Actron digital at searsabout 3 months ago

looks identical in back panel/controls & readout to the craftsman professional
case color is typical actron orange

dont have an msd box xo cant attest to accuracy with abox but it is a real nice piece with digital rpm readout
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B
I have a Sears dial-back light I bought 20+ years ago; I had to stop using it on my MSD equipped car because it was all over the place. I'd check the timing, make a pass, come back and the timing would be 10-12° different. Reset the timing, make another pass, all different again!
Bought a Flaming River cheapo self-powered unit and it NEVER differs once it's set. The Sears unit works well on my other cars, so all I can attribute it to is the MSD.
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M
Bought one of these last winter. Equus 3568. Still figuring it all out.
http://www.equus.com/product_info.php?product_id=3568&category_id=1_20
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I have a Snap On Digital light i bought about 12 years ago. It was crazy $$$, something like $350. But i have to say i have had zero issues with it other than the fact i laid the inductive clip on a header tube and melted it. It still worked but you had to be gingerly about hooking it up. I just sent it out a week ago to get fixed--that one is going to cost me another $100.

Anyhow, enough of my own stupidity, its a digital dial back, has a tach on it too---heck it may do other things i never knew about. But i have to say, it is by far the nicest light i have ever seen or used--and i am sure it has to be made by one of the above mentioned companies for Snap On--in fact it looks similar to the equus unit above, without the swivel head.

Bottom line is, i paid through the nose for it--probably just for the name, but it seems to be super accurate, has been used with points, electronic, MSD 6AL, 7AL2 ignitions and has never let me down and no sign of spark scatter ever---unless it had to do with the timing slack in chain driven engines.
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C
I have seen problems with the Snap on lights and performance engines as they seem to show about 6 dgrees more timing then the lights I use and we use the one wire lites from Flaming River.

We had a circle track customer burn up a piston because his Snap On light was not accurate beleive it or not he did this twice!!!

Here are some good links to look over on lites.

http://www.dragracingonline.com/technical/vii_10-lights-1.html

http://www.chevytalk.org/fusionbb/showtopic.php?tid/173877/
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