how do the mags work at low speed? are they bad for loading up? and for a low sped engine something with a 4500 redline. and how about cruising. hummmmmmmmmmmmmmmmmmmmm thoughts????
i ran one on my model T, 2200 rpm tops...no problem at all, mags work great at any speed, but if you are buying a used one, might want to have it gone through just to be on the safe side...
I'm runnin a Vertex in my coupe...390 Caddy that redlines at about 5500,,,no problems at all! It is a brand new one though...listen to Fur Biskit if you get a used one...
I run one on a small block in my 32 pu. Lota street driving and blowing the doors off every now and then, with a 4 speed what else do you do. No problems in two yrs.--TV
I was wondering the same thing. I just got one myself. From what Ive been putting together is that a good sound mag will work great at slow RPMS and will get a hotter spark when spinning faster. Ive been told to run NON resistor plugs and wires and reduce the gap on the plugs. Should help out....I HAVE NOT RUN IT YET...so this is all "hear say" But it ALL make sense.
If you buy a used one, plan on sending it to someone like Don Zig and have it serviced. The magnets need to be charged, the points and condenser replaced. The magnets are easy to break so dis***embly isn't for amateurs.
I guess its time to discuss mags again.They have always been considered a mysterious device by users but really are very reliable and durable if given just a little consideration. The advantage mainly for mags is they are a 1 piece self contained ign system so in aircraft or small or industrial engine we only need to spin the engine to start, no bat, light weight,usually sealed so weatherproof, unitized so easily exchanged for service, etc. Many different design over the years.When a good spark plug cost 2 hours wages, a small engine coud be bought with or without a mag and the extra cost could be 1/3 the cost of the engine. Speed is more important to the mag than bat and coil ign mainly because there is a low rotational speed at which the mag can't make a strong enough spark to overcome the total resistance of the spark plug circuit.The bat/coil only needs switching on and off(points) to make max voltage. Resistance to high voltage flow in the spark plug circuit is a combination of wire resistance, ground connections,and air gaps(rotor/cap and plug),and now they throw in a resistor in the plug.By the way higher compression PRESSURE can increase the voltage required to jump the plug gap--so now we are talking about something sacred to the performance engineer.Some engine designs are even more sensitive to spark plug gap(resistance) than others.I have found Hemi chambers (alfa & Jag & Triumph)especially sensitive to increased gap.Even proper mixture can affect the voltage required to jump the plug gap.An especialy lean mixture needs higher voltage-that is why in recent years high energy systems and wider gaps have been utilized to get them lit. Modern mags are not as likely to lose magnitism of the magnets as older ones because of design and improved magnets.Cleanliness is crital to the point system because there is not the battery voltage being switched like in bat/coil and because of this the points dont burn as badly.The gap is critical not just because of dwell but the proper timing of point opening in relation to magnet and coil pole position.The points are usually the only adjustable part in this relationship but cam follower wear will change it. Lots more we could discuss but lets let sombody else add. The vertex mags are a highly developed device from a Swiss company(originally Scintilla) and I believe are highly utilized by people making airplane engines from auto engines.That speaks pretty well for reliability I think. It seems those aircraft people throw away a lot of good parts and engines just because they cant get out and work on them.????
Keep the plug gap between .018-.022 or it'll act like it has too much timing and try to eat starter drives and things. Another helpful hint is to start the motor by turning it over with the starter and switching the mag on after the engine is turning over well. T.OUT
A few of things I don't see mentioned are: A vertex mag can be set-up with an internal centrifugal advance. You can tell your mag rebuilder what you want. How many degrees and what rpm you want full advance to cut in. This aids in initial starting and low rpm performance. Remember, mag RPM is 1/2 of crankshaft RPM. A lot of mags for racing are set-up with a locked out advance. I don't use this in my race car, it's too hard to start. For a push start sprint car it's OK. ALSO, Here's my response to a post about tachometers and mags. It was originally posted in the suggestion portion of this forum, so, few folks ever saw it. Quote: Originally Posted by ragtop49 The mag has no direct drive to run a cable . It has one terminal on the base and that is for a ground . Thanks Ya' have a few options. 1) Buy a tachometer that is specifically made to run with a magneto. Not cheap. 2) Purchase a magneto signal converter from AutoMeter that converts the mag signal so you can use a standard ignition system tachometer. With the converter you have to run radio suppression plug wires. If you use solid core wires the needle will bounce around. 3) Send the mag out to a rebuilder and have them install a tach gear drive base. Not cheap. I have one of those converters for sale if you're interested. Used it once with my solid core Blue Max wires. Called AutoMeter and they explained the above. So, instead of changing wires I bought a used mag tach. Think this little box cost me $65. I'll take $45 and that includes shipping. FINALLY: My magman is MAGSARUS in Albany, NY. I highly recommend him for any Vertex mag work. He's not cheap, but who is . His turn around time is fast, and he does what ya' tell him to do and what it needs. Nothing more, so there's no surprizes. http://www.magsarus.com/
The locked advance is used for blown race cars such as blown fuel or alky. If you watch ebay or national dragster you can find a tach drive base to swap to your mag. The vertex has better points than a mallory. The vertex magnets stay charged longer than a mallory but the vertex isn't as hot. On a naturally aspirated engine, this isn't important. If the nostalgic look is what you're after, the vertex is it. They used to use these on 413 chrysler industrial engines around here. For continuos duty, they were poor. I had a large box of that stuff that I sold to a new racer in the early 80's for $20.
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