1974 Dodge Dart Diesel

I know this thread is over one year old. However, I've been prompted by friends to shed a bit of light on these early diesel conversions.

I owned a business in Lynnwood, WA that produced a large number of diesel conversions such as the Darts and Valiants ('American Automotive Engineering'). Dealers dropped off truck loads of new vehicles and my partner and I sent them back with Chrysler/Nissan SD33 198ci turbocharged engines. The Dart in this thread was not produced by our company. There was a previous company that also produced these cars in somewhat limited quantities. That company was known as 'Economy Systems.' Bill Carlson, (long deceased) started Economy Systems. He was a fast-talking swindler. I was drawing unemployment comp at the time and the Employment Security Dept. sent me to Economy Systems on a job interview. The fellow who hired me at Economy Systems was par for the course - an ex-con. He quit shortly after I was hired and hooked up with an attorney. They had high hopes for making lots of money doing these conversions. They were not successful. I managed the shop at Economy Systems past that point. My partner (a family member) came to work with me at ES. He was a professional foreign car mechanic. Carlson took off to Southern California to sell a large Ford dealership on the concept of diesel conversion using Ford vehicles. Carlson died of cancer not long after he cleaned out ES's checking account and ran.

My partner and I worked hard to fold the company up for the stockholders and pay as many debts as possible. The stockholders who were swindled out of their investments were pleased with our dedication and sent us on our way with everything remaining of Economy Systems, including casting designs, etc. We had a zillion customers waiting for vehicles. It was pretty easy to set up our own shop and follow far better practices than Economy Systems ever attempted. Our vehicles could not be distinguished from factory installs. All of the welded parts on our cars were produced by a professional welder just back from the Alaska pipeline project where he earned loads of money. His shop outside of Lynnwood, WA was equipped with state-of-the-art equipment, all brand new. He was a true artist using all sorts of metals. We were located in an industrial park (quite new at the time). We had a large machine shop as next door neighbors. We traded machine work for maintenance on all the machine shop's employees and business vehicles. It was a fair trade. We had professional machinists producing parts for our conversions at costs far less than the going rate. For a small business like ours this was a huge boon.

I notice your Dart is naturally aspirated. This could have been an older Economy Systems conversion. The other outfit, the ex-con and the attorney, could have produced this Dart but I'm not certain they did. If the car was originally sold by Lynnwood Dodge, then that becomes more of a possibility. But there's no way to tell what was added or removed from the original installation a very long time ago. Lynnwood Dodge sold my cars. But the ex-con and the attorney (can't recall their names) undercut my prices by not including items that I considered necessary. Their business didn't survive. They were based in Bellevue, WA. Dishman Dodge in Spokane was one of my best dealer customers. We also did conversions for many other dealers, some not even close to being local. Quality has always been my mantra.

Notice that the engine doesn't sit quite level in the car. That was a hallmark of the early, rather crappy conversions (compared to mine). Oil pans had to be modified to nestle the engine down into place. Our welding shop made those pans appear as if they were works of art. I don't mean to malign your car, though. Keep in mind that I never really wanted to be involved with this business. But as long as I chose to be involved I insisted on avoiding the kludges that others simply took for granted. And our customers were willing to pay the price.

By the way, Wilcap and/or Tony Capana did NOT create this Dart. Tony was a great guy. We knew him and had great respect for the work he did. But he did not put your engine into your Dart. If he had we would have known about it. Plus, he did much better work than what I see in the photos. Tony was another artist in metals. May his soul rest in peace. Last I looked, Tony's kids have kept the business going.

Most of the Darts, Valiants, Dodge pickups and vans that were converted in those days were done by our shop. All used a new bell housing that came with the 6-33 engine in the crate. All engines had to be purchased from a Chrysler Marine & Industrial dealer in the U.S. Chrysler was prepared to take legal action if we ever attempted to bring engines into the U.S. from Canada at a lower price. In the end we were paying about $2400 for a new engine in a crate. The least ever paid years before the closing of our business was $1500 to $1800. The later engines did have the factory Chrysler bell housing that mated the 727-B trans. Chrysler cast that bell housing purposely to interest people in using the 6-33 as an automotive engine. The injection pump was different than the industrial (gen-set) engines (different governor). Also, Chrysler included a vacuum pump to be used for power brakes and other vacuum accessories on vehicles. The flex plate was a 426 hemi plate with smaller bolt holes for a non-hemi converter. We sourced modified converters from a Seattle company. The converters had a slightly higher stall speed, similar to the hemi converters. We experimented with various stall speeds. We used Drivelines NW to modify and balance drivelines. Our product was premium or we wouldn't build it. I had to gut the brand new 727-A transmissions and put the pieces in a 727-B case. Our engine and trans rebuild section of the shop was a spotlessly clean operation. In fact, almost all of our shop was carpeted! All vehicles were new and totally clean. I came by huge amounts of used carpet. It was a no-brainer since the business required really long hours. I used to sleep under cars at night instead of going home. The carpet and the quadro-phonic sound system, not to mention the oversized heaters, made the 5,000+ square foot shop a dream to work in.

The Economy Systems adapter plate casting used in the early days had a significant flange on it that was never trimmed. The factory Chrysler Marine bell housing was painted yellow and could be distinguished from the Economy Systems casting by the obvious flange. One look and you can tell that the factory bell housing is far superior. Unfortunately your photos don't provide a good look at the adapter plate/bell housing. I can't say for sure which one you have. That one photo I saw seemed to be the flex plate mounted on the converter in the trans (??). I should go back and look again. But I'm fairly certain that you have an early Economy Systems conversion. Too bad. I'd love to think that one of my own cars was still alive over 40 years later. Our price out the door for a Dart conversion to a private party was about $13,000. I can't believe anyone would pay that much. We had a lot of crazy people wandering through our shop though. Chrysler, GM, and Ford sent engineers out to have a look. We even did work directly for Chrysler Corp. Those were crazy times for twenty-something kids like us. I never wanted to be involved in this stuff. My father was an aircraft mechanic and I was expected to follow in his footsteps. At least I kept up the tradition by performing my work as if a ground vehicle was expected to fly, and not have any unexpected landings.

The Lynnwood post office would get real pissed at us if we failed to regularly pick up all of the overstuffed mailsacks with our name on them. We did the market research necessary to prove to the Big Three that the American public wanted diesel powered vehicles. We couldn't answer even a small portion of the correspondence.

The exhaust manifold on your Dart is the factory 6-33 manifold. We designed a precision jig (the machine shop next door fabbed it for us) that allowed for cutting the legs from the factory exhaust manifold and positioning them on a rather thick walled piece of 2 1/4" box tubing. The log manifold had a flange to bolt up the RayJay turbo. We used to insulate the manifold. Also there was a port welded into the manifold so we could screw in a sensor for the pyrometer that we included (exhaust temp gauge). Boost gauges were an option. We were conservative with boost. Most engines would never see more than 7-8psi of boost. These engines are over-built and under-rated. But too much boost would be a disaster for the average owner. I saw those engines swallow upwards of 18psi boost. They made horsepower like you wouldn't believe. You had to be very cautious, though. Exhaust temps would climb fast. The pistons from the factory were not forged. They did not use sodium valves. I never saw blown head gaskets.

I've wanted to put this part of my life far behind me and I've succeeded. I'm only speaking now (anonymously I hope) because I see a lot of mis-information about these cars.

Our shop produced a number of other interesting vehicles. I could go on for hours about them. The coolest Dodge pickup we did used a larger factory turbo 6cyl Mitsubishi diesel that had incredible torque. It fit the engine compartment perfectly. The customer used to pull a large boat with it. I recall it had a close ratio 5 speed light truck trans (New Process?). New Dodge trucks and vans with the turbo 6-33 were ordered with lower final drive ratios for driveability. Some were 4x4's. Also, a popular conversion was the Datsun pickups in those days, using the 4cyl version of the 6-33. The 4-33 didn't require a turbo in that small truck. We used the Datsun 4 speed trans with a Hohn 18% overdrive behind it. We created a fancy shift mechanism so that you could split gears (instantly, with only one hand!) and have 6-7 almost perfectly spaced ratios. Those little trucks were a kick in the butt to drive! We had a diesel Datsun truck for our shop truck. 60 mpg wasn't unheard of. That same Nissan 4-33 was a factory option in the Asian market for the Datsun truck, but never imported into the U.S. in those days. It was a bolt-in operation. Our turbo Darts and Valiants were good for 40+ mpg if driven on the highway with a bit of care (speed limit was 55mph then). The 6-33 never came from the factory with a turbo - never. Anyone who has seen one with a turbocharger should know that the turbos were aftermarket.

Sorry, I have no photos. I scrapped all that stuff a long time ago. Towards the end the business became quite problematic. I wanted out while my partner wasn't ready to give up yet. I made my case, though, that the new Darts/Valiants with transverse torsion bars were designed in such a way that the engine would not fit. We were competing with IH who was producing the ScoutII by leaving the gas engine out on the assembly line and 'training' a few IH mechanics to do one-off conversions that were more expensive and crudely assembled compared to a customer bringing us a stock gas Scout for our turbo conversion. The IH Scouts were naturally aspirated at least in the beginning. Again, the 6-33 was never intended by Nissan to have a turbo. They would have used forged pistons if they intended it to be turbocharged. The engine warranty was void if a turbo was installed. Since my partner and I purchased very large quantities of these engines the local dealer who drop-shipped to us (Apex Equipment in Seattle) tended to overlook the turbos. We never had to send a broken engine to them for warranty though. The worst I've ever seen when disassembling a 6-33 was a few cracked valve seats. This was my own fault, for failing to allow the engine to cool completely in very cold weather after a long climb to the top of Stevens Pass where I was once the heavy equipment and sno-cat (grooming machine) mechanic. In cold weather it takes a good half hour of idling for the engine to properly cool. Also in cold weather you need to make darn sure that you don't have any burnt out glow plugs. It's very hard on the poor motor to start cold with less than six firing cylinders. A block heater is a good idea even in a temperate climate.

Unfortunately I have no record of part numbers for the turbo or any idea what happened to the many jigs and specialized castings that we designed. I will say that a log manifold works great. The problem is finding a good welder to weld the cast legs of the factory manifold to mild steel. The idea is not so much to create flow as it is to retain the heat of combustion so the turbo spins efficiently. Of course a large straight pipe out of the turbo is recommended. We used a high-flow performance muffler so that customers didn't complain about noise. Wrapping the manifold helps. You must install an exhaust temp gauge. All injectors must be clean and serviced. No modifications to the injection pump are necessary. If you want to keep the engine alive over a long period of time then keep the boost well under 10psi. We did not use a waste gate. It would be possible to install a waste gate and go to a hotter turbo housing. The problem is that intake temps get pretty high, requiring an intercooler. At 7-8psi the engine performs well and will live to see many years of service. Just don't expect the turbo to give you instant acceleration from a standing stop. Freeway performance and hill climbing is where the turbo helps greatly. Plus the turbo increases efficiency which translates into higher mpg. I recommended the 2.76 ratio 8 3/4" mopar rear end for highway use. The standard drive lines never failed, but had to be cut to length and be re-balanced. Somewhere in my nearly 70 y/o memory is 'B-40.' I think that was the RayJay housing that gave us the standard 7-8psi boost. Or it could have been the hotter housing that we used now and then. At least, if my memory serves me, the B-40 housing is a good place to start. Heaven knows if Rayjay is still in business. I don't even want to look. But if you use a turbo make sure you send it the cleanest oil possible from the engine's oil galleries. Those turbos spin at tens of thousands of revs per minute and the bearings are incredibly precise. Any drag on the bearing will kill the turbo's efficiency.

The weight of the 6-33 was comparable to the factory 318ci gas engine that I instructed the dealers to order for all potential diesel conversions. By the way, someone in this thread mentioned a CJ5 with a Nissan engine. Our shop produced several of these (brand new) for the City of Bellevue to be used as meter reading vehicles. We also gave Bellevue some new Ford police vehicles with the turbo 6-33. They went to detectives who routinely destroyed gas engines by leaving them idle for hours at a time. I've seen the 6-33 run for many hundreds of thousand miles with hardly any maintenance other than injector cleaning, glow plug replacement, and filter changes with premium oil (Shell Rotella). A really good external fuel filter and water separator are essential. My father hounded me until I installed a turbo 6-33 in his '66 Plymouth Sport Fury. That was a clean machine. Decades later the car had rotted away around the engine. After the conversion the Sport Fury ran for over half-a-million miles.

I could go on but I hesitate. If anyone on this forum has questions I'll keep an eye on this thread and respond when I have the opportunity. If anyone wants to send a PM I'll answer so long as I'm aware that the message was sent.