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The following article is from the August 1954 issue of Hot Rod Magazine.
The Buick Division of General Motors never had it so good. After hammering at the door of the "Big Three" for 17 years, the door suddenly opened to find that their 1954 products were in a solid third spot in national sale, behind Ford (1st) and Chevrolet (2nd), a major reversal in itself. So what does this prove? First, it substantiates the predictions of experts who claimed that the new Buick styling would meet with a slight amount of consumer resistance before very wide and enthusiastic acceptance. Sales figures and current consumer demands show this to be true. Secondly, it point out that the majority of the American buying public is more concerned with styling, appearance and prestige than with mechanical functions and refinements. This, to the avid hotrodders of the nation, is a bitter pill indeed, but let's face facts: it's the sorry truth. What the average owner of a '54 Buick doesn't realize is that beneath all that crazy bodywork there is a completely new and superior chassis and steering
layout that puts previous Buicks, and for that matter most other General Motors products, in the "has been" class, as far as handling is concerned. Also, not being particularly performance minded, the average guy doesn't know that with the return of the "Century," Buick definitely shares the top rung of the performance ladder with Oldsmobile, a position the make hasn't enjoyed for many moon, since 1942 to be exact. Possibly, because the older Buick Straight eights lacked good performance in the stock condition has been the reason that they have been all but ignored in the past by hot rodders. "Too much iron!" they shouted. This was true. An unbelievably heavy and inflexible monster, the straight eights were hardly any
inspiration to those who demanded performance, unless they were guided be the engine's sole point of salvation; gobs of cubic inches. In the various fields of competition hot rodding, Buick successes were few and very far between and were brought about by a small but determined group, well versed in the many necessary modifications required to make a Buick get off teh dime.
Most of these straight eight doings are now in the past, what with more advanced engines available, plentiful and relatively cheap. But then, even the new Buick V8's have been almost totally forsaken be lovers of speed and performance. "What can you do with that thing?" they
ask, pointing with scorn to the pin-headed exhaust valve. In the opinion of some, my own included, this is a mistake. There appear to be several modification that can be made to the new Buick engines including "that thing" that will, in all probability, give very gratifying power and performance results. Here's a case in point, the engine shown on this month's cover. Walt Murray of South Gate, Calif. and his part-time partner, Roger Howie, of Bell, Calif., and each with years of pervious Buick competition experience, have arrived at their own solution to the problem. By using a completely stock '54 Buick "Roadmaster" V8 block and bottom end, these boys calculate that they
This shot show 45 degree log on which the Hilborn fuel injector throats are
mounted and the fabricated blower driveshaft housing.
Drawing shows "open" '53 Buick chamber at left, compared to '54 chamber at right.
Note "squish-quench" areas in '54 chamber. Compression is 8.5 to 1 in both cases.
Valve gear layout shows roller tappet, push rod, rocker, springs, intake valve.
Connecting rods are short, sturdy, were designed for high rpm. '53 piston shown.
Bottom view shows that five mains are recessed into stiff but lightweight block.
Hardened crank extension has sprocket pressed onto it for driving blower.
Lighter '54 piston at left, compared to '53 type. Brass pin plugs equalize weight.can raise the brake horsepower figure to above 450, with the aid of a 6-71 GMC Roots-type blower at about 6000 rpm. These figures may sound a bit optimistic but are entirely within the realm of reason, thanks to the basically sound design of teh Buick. This four inch bore, 3.2 inch stroke, 322 cubic inch engine uses stock pistons, connecting rods, piston pins, rings and crankshaft. All that was done to the block assembly was to increase the piston-to-cylinder wall clearance by .001 of an inch and re balance the crankshaft, rod and piston assemblies. The heads were modified only to the extent of slightly enlarging the intake port area nad polishing the surfaces. The exhaust passages were also cleaned out, but these present a problem in that it is quite difficult to cover the entire length of the port without special, long shank tools or extensions. The combustion chambers are fully machined at the factory, assuring a consistent shape, volume and consequent compression ratio between all cylinders.
The valve gear is actuated by a Chet Herbert roller tappet cam with 280 degrees of duration and a lift of .515 of and inch at the valves. Adjustable tubular push rods, made from 5/16 of and inch outside diameter steel tubing are used, which necessitated enlarging the push rod clearance holes in the heads from 3/8 of an inch
to 1/2 inch to prevent binding of the push rods in the sides of the holes. The rocker arms are stock Buick having a lift ration fo 1.5 to 1 and have the push rod seats ground shallower for push rod clearance. The valves are also stock, but were under-cut to reduce their wight and improve gas flow through the ports. The intake valves have a head diameter of 1 3/4 inches while the exhaust valve head diameter is 1 1/4 inches. Both intakes and exhausts seat directly on the heads, no valve seat inserts being used, at a seat angle of 45 degrees. The valve seat width is 1/16 of an inch on the intakes and 3/32 of an inch on the exhausts and in both cases the valve seats are spaced at the outer diameters of the valve faces. Special inner and outer valve springs are used with a combined total of 160 pounds of pressure with the valves closed. The compression ratio is an even 8 to 1, obtained by using the thick (.050 of an inch) head gasket that is standard equipment in cares with convectional transmissions. Dynaflow equipped cars use a head gasket that is .015 of an inch thick, which increases the compression ratio to 8.5 to 1.
Perhaps the most interesting part of this particular engine is the blower. This unit was originally designed for use on 6-71 series 426 cubic inch GMC diesel two-stroke engines. The supercharge pressure, or boost, is between six and seven psi on the GMC engine and maximum blower
speed is about 3200 rpm, being geared to rotate twice the speed of the engine. For the Buick engine, the blower was overhauled by local GMC field engineers, using all new gears, bearings, shafts and seals. The clearance between the outside of the blower rotors and the inside of the case was increased from .006 of an inch to .010 of an inch to allow sufficient rotor to case clearance at blower speeds of 7000 rpm. The blower is driven from the end of the crankshaft by a special extension crank, replacing the crank nut. A timing chain sprocket was pressed onto the shaft and keyed into position. The splined blower driveshaft extension was made for this installation, as was the driveshaft extension housing. A timing chain sprocket, identical to the one used on the crank extension, is pressed and keyed to the blower driveshaft, giving the blower a 1 to 1 ratio in relation to engine speed. The two sprockets are connected by a one inch wide timing chain, specially made for the occasion. With this size blower an engine and the 1 to 1 gearing, boost pressure should be in the order of eight to nine psi, gauge. A slight loss of boost pressure is almost certain at low and moderate engine speeds., due to the increased rotor-to-case clearance, but this should be nullified above 4000 rpm. The manifold beneath the blower resembles a shallow cake pan, with openings cut into the sides that coincide with the intake ports in the heads. This
was fabricated from steel sheet and plate and is screwed to an aluminum plate to which the blower is bolted. On the bottom of the manifold there is a spring-loaded pressure relief valve, set to release at 25 psi, which prevents damage to the blower in case of backfiring through the intake system. Carburetion problems are handled by a Hilborn fuel injection system. This injector represents the only usable remains from Chet Herbert's ill-fated four-cylinder two-stroke engine that demolished itself during a dyno run last year. The two pairs fo injector throats are mounted to a 45 degree adapter, which in turn is mounted on top of the blower.
Original plans called for the injector pump to be belt driven at the front of the engine, but this was scrapped in preference to a combination fuel pump, tachometer and ignition driving unit with a vertical shaft and a pair of bevel gears used to drive a cross shaft. This gearbox is now
Owner-builder Walt Murray poses beside his pride and joy. Expected brake horsepower output is 450 on straight methanol.under construction and when completed will be placed at the back of the engine in the original distributor location. With this arrangement, the Scintilla Vertex magneto that is shown will not be used because of interference with the body of the car. Instead, a dual coil, dual point battery ignition is to be built by Roger Howie, who specializes in such things. Positive lubrication is assured the main, connecting rod and camshaft bearing by the stock Buick oil pump. Low pressure oil is metered to the "thrust" sides of the cylinder walls and valve gear in the heads, which drains back to the pan through the front timing cover, lubricating the timing chain and sprockets in the process. Additional low pressure oil is routed to the supercharger drive gears and any excess oil passes through a drain line connected to the ignition, fuel pump, tachometer drive unit.
Unfortunately, there is no information concerning the power output of this engine, the dynamometer runs being scheduled some time after this magazine goes to press. However, when the power figures are available, they will be published in the "Shop Talk" column of a future issue. And they should be pretty impressive.
All of the special parts of this engine were designed and built during off-hours by the owner, Walt Murray, an architectural and mechanical designer. The present design project, along with several others, is a set of magnesium rocker arms for the Buick that would not only increase the engine speed but would also eliminate the tedious chore of adjusting the hard-to-reach push rods to obtain the proper valve clearances. Roger helped out when he could be spared from the duties of his own shop in Bell, Calif.,
where he is the leading exponent of Buick (what else?) tune-up and go-fast conversions. Both boys are currently putting in as many hours as possible to get the engine and lakester chassis finished in time for this year's Bonneville Nationals. But don't go away! The Buick V8 engine holds many virtues that are unbeknownst to most hot rodders. For big bore, short stroke lovers, the Buick the the most. The four inch bore, used in all models except the 1954 "Special" (which is 3 5/8 inches), is the biggest in the industry. The 3.2 inch stroke is the shortest of any V8 with the exception of Ford and Mercury (3.1 inches), giving the Buick a stroke/bore ration of .8 to 1. With this design, engine torque is not only increased over a comparable long stroke engine, but is spread out over a wider rpm range, adding to the engine's flexibility. The torque produced by the 322 cubic inch 1954 engines varies between 295 pounds/feet at 2000 rpm to 309 pounds/feet at 2400 rpm, depending upon compression ratio and type of carburation. The advertised brake horsepower also varies, falling between 177 and 200 at 4100 rpm.In the Buick V8's produced for the "Super" and "Roadmaster" series in 1953, severe detonation was encountered after an engine had been in use for several thousand miles. This was caused in part by the relatively high compression ratios of 8.0 and 8.5 to 1, for standard and "Dynaflow" transmission types, respectively. The shapes of the combustion chambers and pistons were, however, perhaps the major contributors to the detonation problem. The combustion chamber was wide open, no provisions having been made for surfaces on the piston or combustion chamber itself to act as "quench" and "squish" areas as the piston neared top center.
In any engine, the piston is traveling at its slowest rate on either side of top and bottom centers. The period of slow piston speed at the end of the compression stroke and start of the pwoer stroke is, of course, the time when the combustion process starts and finishes. At this time, the turbulence, or agitation of the fuel/air mixture, must be of such a degree that there can be no danger of the mixture losing its velocity and becoming stagnant within the confines of the chamber. Needless to say, this stagnant or motionless condition of the fuel/air mixture not only invites detonation but smoothness of engine operation goes down the chute. Which is just what happened in the 1953 Buick V8's. This condition prompted Buick engineers to redesign the combustion chamber and piston for the 1954 engines. As can be seen in the accompanying cut-away drawings, the width of the '54 chamber was narrowed by about 25%, leaving two flat spots at the outer edges. The pistons were made with corresponding flats. At top center, these flat areas come within .035 to .070 of an inch of each other, depending on the type of head gasket used. Thus, they form two "squish" areas that squirt the fuel/air mixture into the main combustion chamber cavity, maintaining a high degree of turbulence at a time when the engine needs it most. These same flat surfaces form two very effective "quench" areas that quickly cool the trapped mixture before it has a chance to overheat and detonate. With this arrangement, the combustion chamber cavity is even more compact than before, still offering all the advantages of the "pent roof" design, plus increased turbulence and cooling areas. Incidentally, the 1954 Buick cylinder head assemblies on all but the "Special" series are completely interchangeable with the '53 heads, provided that '54 pistons are also used. However, the '54 pistons are 1.85 ounces (52.447 grams)
lighter in weight than the earlier pistons and the crankshaft must be re balanced for use with the lighter pistons in '53 engines. The size and shape of the Buick V8 combustion chamber, in conjunction with the valves being placed vertically and in a straight line in the cylinder heads, offers something of a restriction in the size of the valves that can be used. This has been the cause of the objections voiced by hot rodders, who sometimes examine an engine and see only the obvious improvements that can be made. But there's more than one way to skin a cat.
Take the Buick camshaft, for example. It is ground from a steel forging, which is unique in the fact that it is the only overhead valve V8 that makes use of anything but cast iron for ta cam. It is certain that Buicks are not bothered by the wearing of cam lobes, a trouble that has plagued every other manufacturer of overhead valve V8 engines. A squint at the valve timing figures shows that the Buick cams for '53 and '54 are by far the wildest stock cam in use in a V8. In fact, from the standpoint of valve timing alone only the most radical "super race" cams can compare with it. The intake opens at 25 degrees after bottom canter, lift at the valve is .378 of an inch. The exhaust opens at 70 degrees before bottom center, closes 42 degrees after top center, lift at the valve is .350 of an inch. This results in a cam with 282 degrees of intake valve duration, 292 degrees of exhaust valve duration and an overlap of 67 degrees. The stock Buick valve gear is good for at least 550 rpm before the hydraulic lifters "pump up." With light weight solid lifters, otherwise stock Buick valve trains have been buzzed in excess of 7000 rpm,
a whopping amount, considering the displacement of the engine. Howerver, the actual points of valve opening and closing are, by themselves, relatively unimportant and no particular indication of the effectiveness of a given cam. More important is the rate of valve lift, or acceleration; in other words, the number of degrees of camshaft rotation between the point where the valve starts to open and the point where the full lift position is reached. Naturally, for best power and efficiency at high engine speed, the faster the valve reaches its full lift position, the longer it stays there and the faster it closes, the better. Passenger car cams are strictly items of compromise between reasonable power, efficiency, and low speed torque, long life of valve gear components and smooth and quiet engine operation. In this respect, the Buick cam is no different, the rate of valve acceleration being comparatively mild to prevent roughness at idle and low speeds, caused by frantic valve timing. In any event, the Buick valve timing specifications show why the small exhaust valve works so well. The valve start to lift early, closes late and is lifted to a height equal to 28% of its head diameter, practically unheard of in this day and age.
Furthermore, theory and past experience inform us that the velocity of gases through the intake system should be close to 200 feet per second for best power, with a safe maximum limit of 250 feet per second before any restrictive effects are noticed. We are also told that the velocity of exhaust gases may safely exceed the velocity of intake gases by 60%, or between 320 and 400 feet per second before the power starts to fall off. Consequently,
it's certain that these limits are not being exceeded in the Buick engine up to engine speeds of 5500 or 6000 rpm. Also that there could be no serious restriction in either the intake or exhaust ports, regardless of the relatively modest valve sizes, in view of the extreme rpms that have been turned with semi-competition engines. The foregoing merely points out that the valves and ports in the Buick engine appear to be a handicap at first glance, but in reality there is no handicap at all, the whole problem having been worked out by some intelligent engineering in a slightly different direction, but giving the same results as larger valves with a lower lift and milder valve timing.
The Buick also scores in the matter of engine weight, always of interest to hot rodders. Previously, the lightest engine for the amount of piston displacement was the Cadillac, which weighed in at about 650 pounds, without the transmission. The Buick, with close to the same displacement, weighs about 625 pounds without the transmission. Actually, the Buick weighs about the same as the '54 For V8 and Mercury engines, which certainly is a factor to consider when compared to an 860 pound Chrysler or a 780 pound Lincoln V8.
We have tried to point out the most attractive features of this engine without overlooking its shortcomings. In my own opinion, the '54 Buick V8 is definitely worthy of serious consideration for competition purposes or as a slightly modified passenger car engine. While the present supply of special equipment is restricted to camshafts, one or two dual four-throat intake manifolds and exhaust headers, there really isn't much more that's necessary to build a good piece of performance equipment. So there it is, hot rodders, take it from here.
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