Should I connect my vacuum advance?

[David B.]

Re: Should I connect my vacuum advance?

Hey, Dan. Just to muddy the waters here, I did a search for dial-back timing lights and found this rather strong comment on a Chevy discussion forum:

>>Just what is so hard to understand about dial back timing lights?

THEY AREN'T FOR USE WITH A SYSTEM THAT USES A DISTRIBUTOR, THEY ARE FOR LATER MODEL COMPUTERIZED DISTRIBUTORLESS SYSTEMS ONLY.

They have a computer lag time built into the dial back feature, so they will read correctly for, of all things, COMPUTERIZED ignition systems.

Now, you want to use a dial back timing light on a distributor type system, leave the dial back feature off, deactivated, set to ZERO, and read a timing tape.

It's just that simple<<

If this is correct, then why spend the extra money for a dial back when our C1s have distributors? Comments from others here?

Dave

[Joe R.]

Re: Should I connect my vacuum advance?

If you find a good source for a dial back timing light, please post it if you would. I'm having somewhat of a hard time finding one here in good-ole upstate NY. But I admit, I hare not tried NAPA yet. All other local sources come up negative. -Dan-

Dan,

I believe this one from Sears is a dial back timing light. I'm sure others will correct me if it isn't!

http://www.sears.com/shc/s/p_10153_1...kType=G1#specs

Joe

[Joe R.]

Re: Should I connect my vacuum advance?

Hey, Dan. Just to muddy the waters here, I did a search for dial-back timing lights and found this rather strong comment on a Chevy discussion forum:

>>Just what is so hard to understand about dial back timing lights?

THEY AREN'T FOR USE WITH A SYSTEM THAT USES A DISTRIBUTOR, THEY ARE FOR LATER MODEL COMPUTERIZED DISTRIBUTORLESS SYSTEMS ONLY.

They have a computer lag time built into the dial back feature, so they will read correctly for, of all things, COMPUTERIZED ignition systems.

Now, you want to use a dial back timing light on a distributor type system, leave the dial back feature off, deactivated, set to ZERO, and read a timing tape.

It's just that simple<<

If this is correct, then why spend the extra money for a dial back when our C1s have distributors? Comments from others here?

Dave

Dave,

I suspect that's garbage you saw on the internet. The dial back timing light is often recommended on this board and these folks seem pretty sharp to me.

Joe

[Dan D.]

Re: Should I connect my vacuum advance?

Hi Joe. Thanks for the Sears link.

I looked at the link, and also at a cheaper but similar model. I guess I have mixed feelings right now. On one model, it talked briefly about distributor and computer settings, but I don't know how it reads advance. Digital I guess. The other model has a dial, but it doesn't look very accurate.

The reviews were not all that hot overall either. Made in China, one failed after a few minutes of use, another said the advance was reading way too high.

So right now I think there may be some truth to the computer ignition argument, but some models may be able to do both distributor and computer. We need to be able to talk to someone technical, if possible, and get the straight scoop. The website is written for a moron to use. Its useless. Then again, maybe we should just buy a balancer tape, and not have to worry about accuracy. -Dan-

[Christopher R.]

Re: Should I connect my vacuum advance?

Sears has a good reputation in general for auto tools. They sell a unit made by Actron that has a good reputation. There's a 10% off offer on their website now. Expires 7/16/2011.

[John H.]

Re: Should I connect my vacuum advance?

Hey, Dan. Just to muddy the waters here, I did a search for dial-back timing lights and found this rather strong comment on a Chevy discussion forum:

>>Just what is so hard to understand about dial back timing lights?

THEY AREN'T FOR USE WITH A SYSTEM THAT USES A DISTRIBUTOR, THEY ARE FOR LATER MODEL COMPUTERIZED DISTRIBUTORLESS SYSTEMS ONLY.

They have a computer lag time built into the dial back feature, so they will read correctly for, of all things, COMPUTERIZED ignition systems.

Now, you want to use a dial back timing light on a distributor type system, leave the dial back feature off, deactivated, set to ZERO, and read a timing tape.

It's just that simple<<

If this is correct, then why spend the extra money for a dial back when our C1s have distributors? Comments from others here?

Dave

The guy who posted that comment obviously doesn't have a clue - not unusual on open forums with people crying for attention.

i've used an Actron CP-7519 dial-back light for many years, and it's just as accurate as my neighbor's Snap-On light, at 1/4 the price; you can map your advance systems in minutes with a dial-back light - terrific diagnostic and tuning tool.