**How to Lock out Mechanical Advance**

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Mad Dart

Mad Dart

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I have a Fresh Rebuilt Mopar Performance Distributor that I will be using for my TT SBM build. I am going to take off the Vacuum Canister and Lock the Mechanical Advance out by welding it. I am using Direct Port EFI and a Megasquirt2. It requires the timing to be locked and all advance duties will be taken place in the tuning of the Megasquirt2.

1) Anybody got any pictures of where/how they did theirs?
2) Know Where to get a Vacuum block off plate?
 
well for the vacuum lock out... i know that stocker dizzy's have the locating tab for the cap on them...
 
Couldn't you just remove the counterweights to do away with the mechanical advance? No welding required.
 
wish4hemi said:
Couldn't you just remove the counterweights to do away with the mechanical advance? No welding required.
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Possibly, I dont know. I have done most everything to a car except lock out a distributor. I usually send them out and have them custom curved for my builds. This one will not need that.
 
805moparkid said:
well for the vacuum lock out... i know that stocker dizzy's have the locating tab for the cap on them...
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Yeah that is why I am asking for the block off plate. It has the locating tab on it. I am sure I could fabricate one if I can't find it.
 
Here's a pic of the guts. I suppose you could just put a tack weld on the slot where the pin on the counterweight comes through, but it shouldn't be that much of a problem to remove them all together.
 

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Mad Dart said:
Yeah that is why I am asking for the block off plate. It has the locating tab on it. I am sure I could fabricate one if I can't find it.
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i know the lean burn dizzy's have them but other than that i couldn't tell you...
 
I guess I just need to tear into it and take a peek. Maybe Don at 4secondsflat.com has the block off plates.
 
Just found an Advance limiter plate on 4secondsflat.com

Advance Limiter Plates 10-14-18 & Lock at 0 Mopar $12.00
 
Seems would be less expensive and easy to convert the one I got. Am I not making any sense? I know the dizzy I have is good.
 
You gonna get credit for that 10hp spacer? :)

Yeah you have to lock the plate plate because of the vacuum advance and the weights. I'd tack the plate so the weights won't do anything. You can weld the vac advance plate up top or use nut/bolts to secure it.
 
crackedback said:
You gonna get credit for that 10hp spacer? :)

Yeah you have to lock the plate plate because of the vacuum advance and the weights. I'd tack the plate so the weights won't do anything. You can weld the vac advance plate up top or use nut/bolts to secure it.
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That's a low blow Rob! That's only on an Indy headed big block! And it was 12HP!! haaaaaaaaa
 
As others have said you can use a lean burn disributor however if your close to a yard you can find a lean burn distributor and just grab the block off plate from it. Shouldnt cost more than a buck. Oh and the block off plate on a /6 lean burn disty is identical tab and all I just checked. I'm sure I could just mail one to ya... the postage would likely be more than whats the parts worth though.
 
Kernel Sanders said:
As others have said you can use a lean burn disributor however if your close to a yard you can find a lean burn distributor and just grab the block off plate from it. Shouldnt cost more than a buck. Oh and the block off plate on a /6 lean burn disty is identical tab and all I just checked. I'm sure I could just mail one to ya... the postage would likely be more than whats the parts worth though.
Click to expand...

Yeah, I mean, come ON. Why tear up a working distributor when you can just about get paid for taking these things?
 
wish4hemi said:
Here's a pic of the guts. I suppose you could just put a tack weld on the slot where the pin on the counterweight comes through, but it shouldn't be that much of a problem to remove them all together.
Click to expand...

you're exactly right, you pull off the springs, tack weld the weights into the full advanced position, via filling the slots with weld. then your mechanical advance is locked.

now for the vaccum advance, unscrew the vac advance diaphram and pull it off, you'll note that the mag pickup will now slide freely. now take a drill/tap a small hole through both plates, run a small machine screw through both. and there ya go. racers have been using this trick forever to just set at 32-34 degrees at all times. starts a little harder, but not too bad with a good bat and starter. plus i imagine the mega squirt will put your timing where ever you want it including a retarded setting during the starter cycle... did it last summer, drive it to the track every weekend and have noticed no street problems with the full lock out
 
johnnymac2k6 said:
you're exactly right, you pull off the springs, tack weld the weights into the full advanced position, via filling the slots with weld. then your mechanical advance is locked.

now for the vaccum advance, unscrew the vac advance diaphram and pull it off, you'll note that the mag pickup will now slide freely. now take a drill/tap a small hole through both plates, run a small machine screw through both. and there ya go. racers have been using this trick forever to just set at 32-34 degrees at all times. starts a little harder, but not too bad with a good bat and starter. plus i imagine the mega squirt will put your timing where ever you want it including a retarded setting during the starter cycle... did it last summer, drive it to the track every weekend and have noticed no street problems with the full lock out
Click to expand...

That's what I am talking about right there! Get it done and NEVER even leave the premises!

This is for a TT Direct Port EFI, SBM application. Initial Timing will be set at 20-23* Locked I am figuring.

The Megasquirt2 will control all Advance and Retarding of the timing.
 
worked for me.lol...i suppse you could just leave the diaphram on it to hold the plate from moving...and just not run a line to it..problem with that is when you pull it apart (as you did already) to investigate the weights..you most likely pulled the diaphram off anyways..and they are a B@tch to get back on...so out comes the tap set...and you're golden...alot of my past motors ran better with the vac advance unplugged anyways...had a 318 that'd spit and sputter and barely cruise with the vac line on...then would run great without it..so it got plugged and no more problems.

also a word to the wiser..depending on your distributor type, there may be several ways the dist guts will go back into the housing...do yourself a favor and throw a pen mark on the housing so you know where you started and it lines up properly...mine conveniently had one alignment pin...with two alignment slots...took several tries to get it back together correctly
 
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