The Bridgeport times and evening farmer., 1919-07-29


 1 and road conditions, both considered, have taught that a weak spark fails l not only to completly consume a lean | mixture when certain speeds have | been reached, but also that 1t fails | completely to consume a lean and | variable mixture or give off the same | power that fat, hot spark does | under similar circumstances 1 The Tnagneto spark is much greater ! in volume and when observed under | pressure it can be seen to throw off | heat particles. or ions, which are not l observed, under the same conditions with the battery spark.
 This proves that the more heat and intensity the spark has, the quick CT complete combustion occurs, with increased power resulting from the impulse; it also proves there is a point where efficiency ceases to be i beneffcially controlled, and over-rap- | i'd combustion could become a. dan gefous explosion
 The 100 per cent. efficiency mark, formance and not by "block test'' for all-'round purposes, Is considered to be best proved by actual road per where adjustments of temperature, carburetor, spark, etc., may be set to exact and varying conditions. The amount of advance required
 
 than with battery ignition, which con- clusively proves that the rate of flame propagation in the case of the bat 1 tery spark is not nearly as rapid as , with the magneto spark.
 Racing and long distance road runs, under changeable conditions of road and weather, with fixed ignf- ton, show conc1usively that the mag neto spark, because of it's heat and i,,tn will ;eI r.; percentage of combustion and reduce more power than weak battery spark under similar conditions, and even when the latter is constantly mani pulated by experts. under changing road conditions, it's power does not equal that of the magneto-equipped engine.
 It is very true that with ideal mixture for a given speed the same power can be obtained from an en- zine whether the spark Is weak or very strong. This condition holds good, however, only when the mixture is ideal. As soon this condition is changed either by throttlins the en- zine changing the level at which the engine operates a difference can be noted. No carburetor constructed up to date has an ideal characteristic curve under all openings of the but l. E. With a given spark the mixture there- fore must be set sufficiently rich to ignite at the leanest point or the curve.
 It has been definitely proved that the hotter the spark is, the leaner mixture it will ignite, especially in cases where the mixture is raw. that is, where the mixture is full of glob- ules in liquid form. A spark contain 1J, crate such globules and cause an ex- plosion where a weak spark would not ignite the mixture at all.
 That is the reason why a hot mag neto spark will fire a leaner mixture, which in turn will mean more power, as most engines, today, under cer- tain conditions, work with a richer mixture than the one that would grve the maximum power, in order to ob tain proper performance on cold days and starting of cola engine.
 Another factor that causes increas- ed power with the magneto ignition is that the magneto for all normal speeds fires at the correct point of timing. The magneto has no lag. It is absolutely impossible to obtain prop CT timing of the battery system by moving the timing lever by hand. This would mean that the lever must be moved continually up and down while | the engine speed increases or de- | creases in proportion.
 It has been attempted to obtain | proper timing with automatic gover- 1 nor. It must be remembered here, | however, that the governor will not 1 advance until the engine speed picks | up and the engine will not pick up | speed until the governor has advanc- | ed. This is therfore 8 circular motion | which in all cases will cause lag 1 and sluggish performance.
 Probably the biggest single reason | for increased power and efficiency, | Is the fact that the magneto spark Ignites the mixture so much more 1 quickly that a considerable less num- ber of degrees advance Is required | Chan would be the case with battery ignition or with weaker spark. Whenever it is necessary to advance the spark ahead of the dead center, there Is negative work" done and whatever burning takes place up to the time the piston starts down, Is dead loss and also has a tendency to reverse the engine and cut down the power AS to the proof of this last contention, you have only to note that on all battery-eQu1pped engines. the battery Ignition system Is given a maximum advance or 40 to 46 de- grees or over whereas the majority of the magneto systems are given an advance of only 80 degrees and never more than S5 degrees. This actual demonstration just mentioned, Is one that cannot possibly be- explained In amy manner except the correct one in which the magneto gets the credit.
 This is a subject that could be dis cussed over hundreds of pages and
 | cal points of view. but tho hard, everyday oommon-sense proof is that in actual use in the hands of the average owner, a magneto spark will produce more power from a lean mix ture. and consequently more miles per gallon of fuel.
 c. W. MORRISON.