Arizona republican., 1917-10-07
BEST KNOWN WAYS TO CONVERT AUTO
 INTO SPEEDSTER

The ordinary stock touring car or [ roadster has certain very definite vir- [ tues and certain limitations. It is built f to give reasonable economy of opera ! tion. to last long under careful hand ling and to develop a moderate turn of l speed; in short, it is adapted to what | we might call general family service. i This is absolutely right, for the aver age owner of such vehicle desires a combination of virtues rather than single outstanding characteristic de- veloped at the expense of the others
 But there are certain conditions where it becomes desirable to increase the speed of a car. The old family ark may have descended to the eldest son, who desires to turn it into a speedster, fitting a Snappy bucket t-seated body in place of the former carry all" The changes may be made largely by the owner himself, though he may have to call in machinist help for certain alter >ations
 The engine is the. first point of at tack in the attempt to inject more speed into the car. As a general thing 1t is desirable to raise the compression. If the engine has a removable head, this part should be machined a few thousandths of an inch to make the tOliipA CoclOH opdCt SIiielttl, UT lIlt cyl finder block may be chained at the bot tom to bring it down slightly: Another method is to use pistons with higher crowns, or pistons of the same type as before but with the pins just a bit lower down.
 In the search for speed it is neces- sary to use lighter reciprocating parts than those generally fitted. Accur- ately fitted aluminium pistons are great help. though cast iron ones are fair. if they are frightened by drilling In drilling an iron piston put the hole in the skirt and not too near the piston pin. Two piston rings are enough for this construction and the clearances for aluminium pistons are twice those allowed for iron parts.
 New connecting rods of tubular steel or in the form of machined I-beam alloy steel are advisable, though it is possible to lessen the weight of this part by drilling the one already in use, but this process weakens the rod The crankshaft is not usually bothered with, though it is possible to have it drilled so that oil from the main bearings will feed the connecting rod lower bearing. Unless it is purposed to run the en- zine for more than half an hour at maximum speed changes in the oiling system by drilling the crankshaft are not essential
 In the process of getting speed in the car the valve timing and lift are vital and both must be altered. The general procedure is to change the valve lift 1-32 of an inch or 1-16 if there is room This latter alteration will require a new camshaft which is too expensive to be generally followed. In the case of a Ford which is being spoeded m a new camshaft to increase the valve lift is not particularly expensive anu is recommended. 1t is a good plar t~ install larger valves than the regular service parts and to do tii,s 1t is
 sary to counter. bore the valve seats This is not an expensive job or the owner may do it himself if he has the tools Using valves 1-32 of an incl larger is about all that can be done safely. The tension of the old springs may be slightly increased by stretch.