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Author Topic:   Lock it out or not???
posted June 27, 2003 10:41 AM
I just wanted to get everyones opinion on locking the mech advance on an HEI distrib. I have locked out the vacume advance. What are the advantages and disadvantages of doing this.

posted June 27, 2003 01:21 PM
One less thing to go wrong. I haven't run a non locked out distributor in over 10 years.
Only con I can think of is they can be hard to start hot depending on how much advance, but I just spin mine over then flip the switch, no worries.

posted June 27, 2003 02:07 PM
agree, lock it out and forget about it. Nothing really to gain by leaving it functional.

posted June 27, 2003 09:29 PM
I run mine welded, with distributor on seperate switch too, does help with starting. If you're running slow enough for the advance to come into play on the track, you're getting passed....lock it out.

posted June 27, 2003 11:35 PM
all you have to do is get one of those wieght kits. use the heavy weights and only 1 light spring. thats how mine is set up. when its cranking it has 22 degrees advance and as soon as it hits 1000rpm its at a full 38 degrees. much easier on the starter.

posted June 28, 2003 09:07 AM
I agree 05, when you get involved in a scuffle on the track, it is very, very important to get back rolling again. If the distributor is locked out and you probably have some extra fuel in the engine from a spin, hit, etc...then you probably just shot yourself in the foot. If they push start you, you are going to the back....if you get started and get going before the flag comes out, sometimes you can get your spot back. I use one of the weight kits as well with the light springs to get it fully advanced as soon as possible...the only difference is, when timing it, you have to bring the motor up to where it is fully advanced to get your timing set...nothin to it.


[This message has been edited by jammin (edited June 28, 2003).]

posted June 28, 2003 10:37 AM
me too. i use the mechanical advance for the same reasons already mentioned. it's never given me a problem. it doesn't really matter when all the advance comes in. as long as it's all in at less rpm that you'll be seeing on the track under race conditions. mines all in(28 degrees) at 2400 rpm. easy on the starter and blasts off without a problem if it's parked sideways on the racetrack, lol.

posted June 28, 2003 11:01 AM
I've never had a problem with my mech advance either.

posted June 29, 2003 01:38 PM
no problem here

posted June 30, 2003 09:35 AM
If you are worried about getting it started then wire your ignition so you can turn the starter over without firing the ignition. hit the button to spin it over a couple times then hit the ignition switch to fire it. We have no problem starting a 13:1 alky motor anytime on or off the track.

posted July 02, 2003 06:06 PM
I have run both locked and unlocked distibutors about equally over the years.
now I run locked.
the reason being is that at times the centrifical force applied to the weights can bend the pins and allow more advance then you want and detonate the engine especially if you run the heavy weights as mentioned above.if you get a curve kit it actually comes with lighter weights so they should be used to help prevent bent pins.
also when the pins bend and allow more travel by the weights the weights can come in contact with the rotor and can hang up(causing locked advance,more than you bargined for)or even breaking the rotor and letting pieces fly around under the cap.
for my money locked is better for durability.
most guys use a bump button and seperate power switch which is easy to do and you can also wire in a bump button on each side of the firewall in the engine compartment for use when setting valves or even points for those using them still,heck compression testing is easier this way also.

posted July 03, 2003 12:06 AM
When I have used light springs from a weight kit I have detected flutter where the weights bounce. SLEEPY

posted July 04, 2003 12:45 AM
What about vacuum rules? How much difference does locked vs. unlocked make when your tryin to pull 15" at 1000 rpm?

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