installing any ignition into a racing engine that has had the cylinder
heads milled and block deck milled, or even an intake manifold change, you
should install the magneto or distributor into the engine without any
gaskets to make sure the ignition unit doesn’t bottom out on the oil pump
drive and cause a bind. On some big blocks the bottom of the gear will hit
inside the engine block if allowed to go down too far and either one of
these problems can bind the magneto or distributor up and cause damage to
the mags thrust washer and more than likely cause the magneto to retard
out of time. If you run into this situation we have low cost shim kits to
raise the ignition unit up a small amount or magsarus can install a fully
adjustable slip collar on the vertex mag so the mag will fit into any
chevy v8 engine from s.b.c.to b.b.c., standard cam location to raised
cams, low deck blocks or high deck blocks.
The next thing that is important is to check the mag gear to the cam gear position. For this you need to get some machinist blue dye, or some white grease works or a magic marker. Paint the mag gear, Reinstall the mag into the engine, Rotate the engine over a couple of times, Remove the ignition and look for the mesh marks on the gear and just shim or adjust the slip collar up or down as needed so the cam gear will be driving the ignition gear in the center.
The number one cause of premature wear on the drive gear brass or steel, magneto or distributor is excessive resistance from driving the oil pump Every time you start the engine up with cold 50W oil these engines can produce as much as 80 to100 psi at idle. It is very important to keep the RPM’s low until you get the proper oil temperature, or the proper thing to do is to preheat the oil, early in the year when the outside temperature is down to 50 degrees it takes a lot longer to get to 200 degrees. The biggest selling oil for steel block engines with minimum bearing clearances is a 10/30 synthetic. This oil is easy on the oil pumps and distributor gears and will make more H.P. .
Now with engines that use external oil pumps you won’t get any wear on the magneto drive gear and you can expect to get a good 10,000 laps on a circle track engine on one gear, where as with an internal oil pump engine you usually can expect to replace it every 1200 laps, a noticeable difference. and there is also some low cost cam cores that have a poor machine finish on the cam shaft gear that is eating up distributor / mag gears in dry sump engines. you can tell if you have one of these cams as the rough machined finish will show up in the ignition gear where it is wearing the ignition gear out.
Ignition wires are a subject that a lot of racers ask about, for instance, what brand, spiral core, copper core, stainless steel core, armiad core, carbon core etc. Well I like to keep things as simple as possible so my suggestion is to use 8mm solid copper core wires for a perfectly simple reason and that is when you go out and purchase a new ignition that is putting out more voltage and more amperage, why would you ever want to put a resistor between the ignition and the spark plug, and that is just what all of those wires do except for the copper core or the stainless steel core. These spiral core wires suck up the amperage before it reaches the spark plug and in turn makes a weak ignition. 10 mm wires are not going to perform any better than 8mm wires.
The one thing to remember, copper is the number one electrical conductor. It is used everywhere for everything in conducting electricity. Resistant spark plug wire like the spiral core absorbs lots of amperage before it reaches the spark plug. Some ignition systems have to use these wires because the electrical magnetic field produced around the wires is strong enough to send bad signals to the electronic boxes. With Magnetos and our racing HEI distributors, there isn't any problems in the performance, it is better. And I have not seen any problem with these wires affecting the msd rev limiters that some of the sportsman classes have to use in our area.
Problems can a cure when you have high voltages being induced and removed from a conductor. when you feed a spark plug wire with high voltages it creates a magnetic field around each spark plug wire , when the voltage passes through #5 spark plug wire on a Chevy engine as the electrical magnetic field collapses it will collapse into the wire that is closest and parallel to. If it happens to be the #7 wire, it could possibly fire #7 cylinder under perfect conditions and at that point in time #7 piston is way down in the cylinder, and if it happened to ignite this cylinder, it would try to push the piston backwards and creating a problem. Just remember to space your #5 and # 7 wires or on the c fireing order cams you need to space #1 and # 3 wires the rest of the wires I like to just let them hang or criss cross them so they are not parrellel to each other.
All spark plug wires will burn when placed on 1,200 degree headers, so make sure boots grip the spark plugs well, otherwise they will fall off during the race; that is really all on ignition wires. if you install or put new boots on spark plug wires you should use a silicone dielectric grease. And on my engines I will run my number one wire across the top of the engine and down the front of the head and up to the spark plug . this does two things the first is it gives you easy access for timing the engine and it gets the wire away from all other plug wires for a good accurate timing light signal.
Ignition unit maintenance. they should be inspected once a year for wear and tear just like the rest of the engine components. proper timing, bushing wear, primary and secondary output, drive gear condition, cleanliness, etc. There really isn’t much the average racer can do other than to check the point gap on a magneto and pull the ignition out throughout the year and check the drive gear for wear and the bottom shaft bushing for excessive wear blow the distributor cap out and wipe it clean. Check for cracks and chafing spark plug wires.
I would also like to note: HEI distributors like voltage 16 volts seems to to be the ideal set up with out a alternator. The Magsarus Racing Distributor will run perfectly with only 12 volts input and pull power up to 8,000 RPMs. If you were to install an alternator, you would gain more output voltage and consistency from one event to the next. You could drain the battery and bring it back and still your input would be 14 volts and your performance wouldn’t be affected by a weak battery. I have been asked many times if the voltage converter boxes work and I did some test and they do work very well.
Also when timing a racing engine you always want to time the engine at 3000 to 4000 rpms that is so you get all of the moving parts that are related to the ignition timing headed in the same direction and the timing marks will be steady. Some engines at low rpms can be fuel rich and cause the engine to run a little ruff and that causes the timing marks to move around. and the first thing you think is there is something wrong with the ignition. It is very important to keep your carb as lean as possible at idle to keep the cylinders clean, that means the idle mixture screws need to be in as much as the engine will let you with the butterflies closed as much as possible so the transfer slots are not exposed from the intake side of the carb. If the engine wont idle like that you can drill a .098 to .120" holes in the butterflies to allow air to enter into the engine with the butterflies nearly closed on both primaries and secondary. If that doesn't keep the engine clean it will need some expert help. Always do your carb adjustments at the engines running temperature. The 602 crate engines are noted for being very rich at low engine rpms. the carb needs to be modified and the distributor needs to be modified, and the problem will be fixed.
Another thing to be aware of there are a lot of new designed high velocity headers being used in racing and there soul purpose is to pull more air and fuel thru the carb and into the eng. that is all good when you are accelerating up but in circle track racing you have two off or mid throttle corners and these headers off throttle will pull unwanted fuel into the engine they act just like a vacuum cleaner and when you go to accelerate off the corner the eng can be rich with fuel and create a hesitation or blubbering. Just remember that in the off or part throttle carb positions are very critical in circle track racing and just because a carb works perfectly on the dyno it may not work so good on the race track. learn to read your spark plugs and don't be afraid to change them as the engine will always perform better with new spark plugs. If you have this problem of blubbering off the corner let your carburetor guy know that you are using high velocity headers so he can tailor the lower blade angles of the carb to pull less fuel these days you need a carb tailored for each individual eng. to be perfect. Every carb guy seems to think differently on how a carb is supposed to work and if you get hooked up with a carb guy that thinks the dyno is the holy grail of tuning you could be in for some problems with your circle track engine.he mother figure of a family, with babies and young children joining the female models.
on spark plugs always use a plug hot enough that it wont foul out at low
rpms and a plug that wont discourage you from changing them every few
races because of cost . Don't buy into the latest design racing plugs
with v cut ground straps or center electrodes these plugs do nothing but
skip and misfire. I like to
see just a plain design non resistor non protruding cheap plug autolite,
champion, NGK ,in that order. The autolites and the champions with the short
ground straps are the best to use in most racing so as to not get pre
ignition do to the ground strap getting so hot that it glows.. Spark plugs
in a high cylinder press engine for racing don't last like they do in
street vehicles they are subject to extreme pressures and fuel with
extreme amounts of lead to suppress detonation and the spark plugs have to
fire under these conditions all of the time. After just one night of
racing on a brand new spark plug it will require an additional 6000 more
volts to fire that spark plug under the same load. That is why some plugs
will run a little longer than others before they start to misfire and have
intermittent skips. Have you ever heard a car go
out on the
race track for the first time of the night for warm ups and the engine is
popping out the exhaust, And after about 1 to 2 laps the car is sounding
normal, 99% of the time That is from a fuel fouled spark plug, or the engine / spark plugs
not up to temperature, what is happening is that the lead in the
fuel is acting as a conductor for the electricity to flow down the side of
the porcelain insulator and the electricity goes to ground instead of
jumping the gap when the cylinder is under a load and is more subject to
happen with colder number spark plugs with wide plug gaps. note that this problem
only happens with leaded gas and will never happen with alcohol.
When ever you have a problem with
the engine skipping and misfiring always check the spark plugs 1st for
color, make sure the porcelains are clean and not real dark the first race
on new plugs they should show a flat white and the next race they should
be a slight tan color. Check for possible broken porcelains do to
detonation, to much timing ,or the ground strap closed up from a piston
hitting it. if the ground strap is bent then the spark plugs need to be
indexed and the next time the engine is overhauled have the engine builder
notch the pistons for spark plug clearance which will also make the engine
perform better, if the engine is really breaking up so bad that it wont
take any throttle but will idle normal and run partial throttle check for
water in the fuel. when you get water into the carb it will make the
engine sound like the rotor broke off and the ignition is out of control.
3rd if you experience a slight little pop or mis towards or at the end of
the straight 99% of the time the engine is leaning out and needs more jet
in the carb. if you have one cylinder that is skipping . check the plug,
check the valves, check the plug wire, check for a cracked cap, injected
motors check the nozzle for that cyl..
Another tip for everybody who thinks that a ignition rev limiter will save or stop your engine from revving to the moon when the drive line breaks. wrong! I have tested on my ignition machine all kinds of ignition rev limiters and they all do what they are intended to do. you can run the machine up to the rev limit and it will stop the ignition. But I can tell you from my own experience that a ignition rev limiter will not stop a engine from over revving when the gas pedal is down and the drive shaft breaks or when the rear end jack shaft breaks, even if the ignition is shut off the engine will rev so quick that it will run right thru and there is nothing that will stop the engine but time. So save your money kids. I don't sell or promote ignition rev limiters any more after two times that I broke the drive line and after several discussions with other car owners and engine builders. what I found to be the only cure for me was the light weight titanium ex valve train with a lot of piston to valve Clearance. Sprint car engines are very hard to tell if you have an ignition or fuel problem they both will sound the same. as long as i have been in the mag business, 32 years,. 70% of the supposed problems with mags come from alcohol fuel injected engines, not gas carbureted engines. and 90% of those fuel injected mags with out question didn't have any problems, but it is still worth having the mag inspected and serviced, but what aim saying is these fuel injection systems have many areas to go bad along with the alcohol and weather changes, far more than any mag could have a problem. a magneto doesn't care what the weather is but the alcohol sure does. the cars running on gas and a carburetor run week to week all year long with out any problems. alcohol fuel injected engines are constantly having to adjust the fuel system to keep the engines from being to rich or to lean. A rich engine will sound loud a lean engine will sound quiet and will have an exhaust pop sound. and when the weather is humid the engines will be flat. there is many components to a fuel injection that can go away and change from race to race. the worst thing that can happen with fuel injection is have it sit and not be run do to corrosion from the fuel. if the engine is not going to be used after the last run for three days the entire system needs to be cleaned and lubricated.