The Internet Craftsmanship Museum Presents:

Gary Conley of Conley Precision Engines is shown with his latest offering, the Stinger 609. There are not many people with the skill, knowledge and determination it takes to make a living doing what they love, but Gary is one of them. (Click on photo to view a larger version.)

Those who know of the Conley V-8 already know of the Conley name. The story of the production of that engine, plus the Viper V-10 and the tragedy that resulted in the design of the new Stinger V-8 is one of both talent and perseverance. There are not many people who can make a living doing what they love, but Gary has managed to do it despite setbacks that would have caused most others to give up. Luckily for the world of fine small engines, Gary Conley didn't, and we are about to see his latest creation hit the market. Here's his story as adapted from his own web site.

“Perfection is almost good enough.”

The motto at Conley Precision Engines is “Perfection is almost good enough”. This is a motto that Gary tries to live by daily. He says he has found that it is better to explain a delay than apologize for the quality of workmanship later on. His business has been in the same location and has grown steadily over the past 30 years, and he firmly believes this longevity was due in part to the way my customers are treated. The customer loyalty he inspired though the quality of his craftsmanship paid dividends when he really needed it as you will see when you read the rest of his story.

A start in teaching makes way for chasing his own dream

After completing his Masters Degree in Industry and Technology at Northern Illinois University, Gary spent about five years teaching Vocation Machine Technology at Morton West High School in Berwyn, Illinois. During this time he involved many of his advanced students in machining and constructing various steam and internal combustion engines.

When education became more “baby sitting” than teaching, he decided to start his own business with one product, a very limited budget, and a lot of hopes and dreams. He stresses that without his wife, Cheryl, none of this would have been possible. She has allowed him to “chase a dream” for almost 30 years.

A Conley V8 of the original "427" style sits atop an engine test stand complete with radiator and fuel tank. This particular version is fitted with a supercharger and stainless steel exhaust. The new engine differs substantially from this original engine design. (Click photo to view larger image.)

The first V-8 engine was crude in comparison to his current engine. It was made completely from billet. Each component was hand made without the use of any CNC equipment. That has been almost 30 years ago and he proudly notes that several of the original engines are still running. He says, “I must have done something right.” During this time the engine went through some major changes. Being on a limited budget, it was difficult to make significant running changes in the production and machining. As monies became available it was spent on new machines. The most significant machine was an Anilam CNC retrofit to his current Bridgeport. By today’s standards, this machine was very slow, but for the first time he really had the ability to make interchangeable parts. By the way, this machine is still in use, and although slow, it is still extremely accurate. He now has three other pieces of CNC equipment. Since he is not a “job shop” there are several dedicated machines for a specific purpose.

Going from billet to cast parts

Another significant change was having a lot of the parts cast. Some of the parts were “sand cast” while others were either “die cast” or “investment cast.” Not only did this alter the appearance of the engine but allowed for considerable internal changes. The most notable of these was the investment cast crankshaft and connecting rods. This allowed Gary to increase the bore from .750 to .952. Over the years there have been too many changes to list.

Chrysler asks for a model Viper V-10

There were plenty of ups and downs during this time but in 1996 two representatives from Chrysler approached Gary. Since he was already making a V-8 engine they asked if he would consider building a ¼ scale Viper V-10 engine? At that time he was contemplating building a ¼ scale V-12,and after some serious thoughts the V-10 seemed to be the logical choice. After going through and receiving a licensing agreement from Chrysler the next step was to get a full sized engine for the purpose of “reverse engineering”. One day he got a knock on the door and a truck unloaded a complete Viper V-10 engine in his driveway. At that point he began to wonder, “What have I had gotten myself into?”

The 1/4 scale Viper V-10 engine. (Click photo to enlarge.)

Since this engine was mainly a façade with limited internals, it was totally dismantled and each piece was then analyzed and evaluated to see if the engine could actually be reduced to ¼ scale. Little did he know that this was only the beginning of a very long “uphill battle.” Some of the molds he made himself, but a good friend of his, Ken Bennett from Topaz Engineering, made one of the most complicated molds. It was the mold for the head and runners for the intake and exhaust ports.

Overcoming two major problems

The problems that were encountered are too numerous to list. Two of the major problem areas that had not been considered were the ignition system and the oiling system. Keep in mind that voltage cannot be scaled down. To solve this, the alternator housing became the distributor. It had ten electronic sensors and one rotating magnet. The signal created was then sent to another circuit that told each coil when it needed to fire. After numerous failures it was discovered that the RF interference was burning out some of the sensitive components. The solution was “magnetic suppression wire.” At the time this did not exist in small size, but he contacted Delphi Packard, and two months later he had 10,000 feet of small diameter magnetic suppression wire. This eliminated the first problem.

The other problem was oil control. There was always plenty of oil, but it was almost impossible to scrape the oil from the walls of the cylinders. This alone took him over nine months of twelve-hour days to solve. Remember, oil control rings for this size engine are not commercially available. The entire project should have only taken one to one and a half years. In actuality it took almost 5 years.

 With production near, tragedy strikes

After five years of had work, it was all about to pay off. Then Gary received possibly the most devastating phone call of his life. The foundry that was doing all of his castings had been consumed in a catastrophic fire that destroyed everything. All of the V-10 molds had melted down to large puddles of aluminum. Even the molds for the V-8 were destroyed. Over $350,000.00 in molds and five years of hard labor were gone, and there was no insurance to cover any of his loses!  Only one V-10 engine was ever completed and is now in the possession of an avid engine collector.

He says for the next three days after getting the bad news he just sat in his office and cried. If that were not bad enough, all of the deposits for every engine had to be returned. It would have been very easy to declare bankruptcy, but for Gary this was not an option. He had built a company on honesty and integrity and could not do that to his customers, but at the time no other alternatives seemed to present themselves.

Taking business in a new direction keeps the dream alive

About that same time the company that was making the model carburetors that were used on his engines was being sold. With some very strong “soul searching” and lengthy conversations with his wife, he decided to purchase the entire line of Perry products from Varsane Manufacturing. This included not only the model carburetor line but also the model engine pumps and fuel control valves. This purchase proved to be his “saving grace.” Slowly, all of the deposits were returned and he started to see a little light at the end of the tunnel. Things have continued to improve, and after exhausting his entire existing V-8 inventory, in the fall of 2005 he decided to build another V-8 engine.

Surviving V-10 molds give life to a new V-8

The one thing that he had retained from the fire was all of the masters from the V-10 engine. Instead of trying to revive the V-10 engine, the decision was made to modify and shorten the V-10 into an all-new V-8 engine. There is something that is called “transferable knowledge”, which became very evident when he decided to build the new engine. Remember, almost five years was spent on its design and construction. Some of the internal components did not change, and since he had a lot of parts in stock he put them to good use on the new “Stinger 609” engine. Surprising, the only molds that survived the fire were the mold for the head and the mold for the intake and exhaust runners. With a lot of measuring and careful machining, the mold for the V-10 head was shortened to make a great V-8 head. The runners did not change. Somehow, some way, all of the masters were modified for the new Stinger 609 engine. The rest, as they say is history, and the new engine is now in production. Gary wishes to thank the many customers who stood by him through good times and bad.

The Stinger 609 is based on modified and reclaimed molds for the scaled down Viper V-10, sharing a high performance lineage with one of the world's most famous sports car engines. (Click on either photo to view a larger image.)

About the new Stinger 609

The name is derived from the displacement: 6.09 cubic inches or almost 100 cc. This engine is the culmination of almost 30 years of knowledge gained in the designing and construction of model engines.  The new Stinger possesses no parts used in prior V-8 engines. The bore is 1.00", with a .970" stroke. It weighs about 11.25 pounds and measures approximately 14" long (from the front timing belt to the end of the transmission), 6" wide, and 8-1/4" tall. The supercharged version will be about 10" tall.

Among the numerous innovative features like the large oval shaped intake ports, "D" shaped exhaust ports, and investment cast parts, two bold attributes stand tall: the dry sump pressurized oiling system and a full ignition system. The engine even has a user replaceable oil filter. For those unfamiliarity with dry sump oiling, it simply means that oil resides in a holding tank, rather than a conventional oil pan. From the tank it circulates throughout the engine. The oil that does collect in the pan is simply pumped back to the holding tank. There are two separate "Gerotor" style pumps to move all the oil. An important side note: the test engine held about 40 lbs oil pressure at idle and 80 lbs oil pressure at 9,000 rpm. The dry sump oiling system not only adds more oil volume but aids in engine cooling and makes sure that there is plenty of oil during hard acceleration or sharp corners.

The spark plugs have a 10-40 thread. As always, the new Stinger 609 V-8 will have an electric starter as standard equipment. No hand held electric motors or something that fits in a box below the engine, but rather a 12 volt electric motor that is a fundamental part of the engine. It can be activated manually or via the transmitter on your remote control. The centrifugal clutch is also included. The standard engine includes “Zoomie” style exhaust pipes. Options include cast stainless steel exhaust manifolds (plain or polished), painted valve covers and intake manifold, supercharger, and high duration camshaft. A transmission with forward-neutral-reverse is expected in the very near future.

It all takes time, and Gary is proceeding as fast as he can without compromising quality. He has started an "update" page on his own web site where he keeps future customers informed of the weekly progress. Most people don't understand the complexity of an engine and the many processes that must go into the various parts. One thing that Gary mentioned several times in our interview with him was that he will not cut corners. As he says, "I'd rather explain a delay than have to apologize for a mistake."

Performance Data

Each engine will be dyno tested and is expected to put out over 6 HP at 9,500 RPM in naturally aspirated form. Data on the new engine will be posted as soon as it is obtained.

Are the paving stones really big or is this V-8 powered '23 T-bucket roadster that small? It's done so well it's hard to tell in this photo, isn't it? (Click on photo to view a larger image.)

A '23 T-Bucket roadster designed to showcase the engine

Available to showcase the engine is a “T-Bucket” roadster that features a stainless steel rear end housing with differential, powder coated steel frame, oil-filled shocks, stainless steel exhaust, front wire wheels, “Halibrand” style rear wheels with knock-offs, operating headlights, carpet, leather seats, burled walnut dash with full (simulated) instrumentation, windshield, aluminum firewall and stainless steel dropped front axle with multi-leaf springs.

Engine test stand

A self contained engine test stand is also available. It includes a custom hardwood base that conceals the battery and electrical components and is finished and wired, a radiator, fuel tank and powder painted steel frame. A photo showing the original engine on a similar stand is shown above in the article.

Gary's Shop

Gary in his shop. In the photo to the left he is in front of is EDM. In the next photo he holds the new Stinger V8 while standing in front of his CNC milling machine. More of his machines can be seen below. (Click on either photo or any of the photos below to view a larger version.)

Gary's shop is not as large as you might think considering the number of operations required to produce a line of engines. He has a Hansvedt EDM and an Emco mill that has been converted to CNC control. He has also installed a complete Sun engine analysis station for future testing and evaluation of the engine's performance. He also lists the following tools:

Rockwell hardness tester—Although this is not used very often, it comes in handy when you need to know how hard the metal is you are trying to cut or grind.

Optical Comparator— It has a lot of applications but was just recently used to determine the exact angle and position of the oil holes in the crankshaft. 

Sunnen honing machine—This machine is used to hone the cylinders and “line hone” the blocks for the mains and camshaft hole. It is absolutely critical that these surfaces be dimensionally accurate, straight, and have the proper surface finish. Since the block is about 5.250 inches long it takes a lot of experience, knowledge and effort to achieve the desired results. Once again, if there is any mistake made during the honing process you end up with a very expensive paper weight.  

Granite surface plate with digital height gauge—A cabinet beneath it is full of every conceivable measuring instrument, gauge and layout items.  

Brown & Sharp tool and cutter grinder—This is a “dedicated” machine which is only used for finish grinding camshafts and crankshafts. This, like almost all of Gary's machines, is equipped with a digital readout.

CNC Machining Center—This machine will repeat to .0001 and has a “chip to chip” time of about 5 seconds. Chip to chip, refers to the amount of time needed from when the tool stops machining, retracts, changes the tool, then rapids to the next operation. It also has a “rapid” movement of about 975 inches per minute. This is extremely fast and if you are not careful, or there is a mistake in the program, it can get real “ugly” real fast. Once the machine is programmed, Gary can literally walk away and be doing other work while the machine does almost everything. He says he cannot overemphasize the importance and the need for a machine with this kind of accuracy. It simply means that each part is “identical”. The interchangeability of parts is absolutely critical. This machine also has what is called “ridged tapping” which means the tap is fed into a pre-drilled hole at a pre-determined rate and depth. Once the depth has been achieved, the spindle stops instantly, then reverses and retracts at the same feed rate. Gary taps a lot of 2-56 holes with very little breakage. The machine can tap at up to 3,000 rpm. This is really moving. More and more of his tapping operations are using what is call “thread forming”. Simply stated this is when the metal is not cut with a tap, but rather the metal is displaced and “formed” into the shape of a thread. This not only gives a stronger thread, but allows him to tap some very difficult metal. A good example of this is when he had to tap some 2-56 holes in the 303 cast stainless steel that was used for the differential housings. No matter how he changed the feed and speed rate he was breaking a lot of taps. Once he started using the “thread forming” tap, he was able to tap 234 holes with just one tap. This machine does about everything in the way of machining. He jokingly says he is working on a way to program it to make his breakfast.

CNC Lathe—The CNC lathe is used to make a lot of small parts, like pistons, wrist pins, valve collets, idler wheels, shafts, distributor housings, etc etc. This machine has what is called “gang tooling” which means there are a number of tools that are all attached to the top of a X-Y table which is attached to the bed of the lathe.  Although not as fast as the CNC Mill, it is, once again, extremely accurate. The lathe is equipped with a bar feed that continually feeds material into the machine. Once the bar is used up, the machine stops and another bar is added. The two CNC machines are situated close to each other and it is very easy to run both at the same time while doing other manual operations.

Drafting table—Gary still uses a traditional drafting table for a lot of the design and layout. He understands that the computer would be faster and probably more accurate, but it takes a long time to learn “CAD” and right now he doesn't have that luxury. Maybe sometime in the future.

Manual lathe—A lot of operations still need to be done on a manual machine. It may be as simple as drilling a hole or require several days of machining. A good example of this is the camshaft blank that needed to be made for the new mold. When making the blank an exact amount of “shrinkage” needed to be calculated. Every dimension had to be made larger by .024. Take the cam lobe width, for example. The finished dimension was .128, when casting the lobe needed to be .128. This may not sound like a lot but multiply .003 times 16 lobes and you get .048. Add this to all the other dimensions and you can immediately see why the digital readout on the lathe is so critical.

Bridgeport vertical milling machine—The same is true with this machine as is the lathe, especially when jigs and fixtures need to be made, or a mold needs to be fabricated. The list is endless for some of the manual machines.  

There are a lot of other machines which are not pictured as well as a significant amount of measuring equipment. These include but are not limited to micrometers that will measure up to 12", a digital clinometer for measuring exact angles, setting gauges, dial indicators of every description and size, digital calipers, gauge blocks, pin gauges to 1", bore gauges, etc. etc. A second rolling tool box has drills of every size and various lengths, reamers, end mills from .016 to 1.25", carbide cutters to 5", taps and dies from 0-80 to over 1". There is also a vast array of hand and power tools plus things like wrenches, sockets, files, clamps, pliers, cutters, screw drivers, etc. etc. He hasn’t every started on the number and kinds of saws that he has. As you can easily see, there are a lot of items needed to make a small manufacturing facility operational. He has been designing and building model engines for about 30 years and during this time has acquired a lot of tools and machines. Gary says, “I guess that I am really a 'tool horse.' Tools are good, more tools are better.”

Show Biz Plugs

Gary is seen her with Tim Allen, who plays Tim "The Toolman" Taylor on TV's Home Improvement. This was taken during a season-opening episode called "A Tribute to Engines." The second photo shows Gary with Richard Karn, who plays Tim's shy but able assistant Al Borland. The engines were featured on the show, and Tim also mentioned running the engine in an interview on the Letterman Show. Gary spent almost a week watching the filming and said it was an interesting experience. (Click on either photo to view a larger image.)

For more information, prices on engines and bodies and the latest updates, see Gary Conley’s web site at: http://www.conleyprecision.com.

Here are a number of examples of Gary Conley's work:

(Click photos for larger images.)

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