The Logic Module, found under the right kick panel inside all Chrysler turbocharged cars, is the brains behind all the engine functions.

Air cleaner cover was polished in area indicated by pointer.

Stock exhaust (right) was replaced with a custom-bent system using 2.5 inch stainless steel tubing, a Sonic Turbo muffler and no provisions for a catalytic converter.

I removed the turbocharger compressor inlet elbow, the air cleaner hose-to-throttle body adapter and the air cleaner cover, eliminated all the casting flash and polished them internally. Installation was completed with a K&N air filter element. The intake modifications I performed were similar to what a person would do to an intake manifold on a V8 engine. However, I had an easier time since most of my components were plastic. A road test revealed a remarkable difference in driveability, and it was obvious the drag strip times would correlate. The strip times confirmed this: a slowest time of 15.75 at 87.71 mph and a fastest of 15.65 at 88.75 mph. Horsepower calculations showed the better-breathing 2.2 was providing at least 165 hp; that's another 20 on top of the 18 added by the Logic Module and higher octane fuel. Since my 2.2 turbocharged engine was approximately 30 percent more powerful now than it was in its stock configuration, I began to get concerned about driveline breakage. A little research educated me a bit. The older FWD transaxles had a differential mounting configuration that was not capable of sustaining wide open throttle, drag strip-style starts. I also learned that Chrysler had corrected this problem in the '87 and newer automatic transaxles.

PHASE THREE

The third step in my quest for a 14-second FWD automatic was the hardest to complete and the most expensive. I was aware of the transaxle redesign in the 1987 and newer Chrysler turbo cars, so I limited my search to one of those. After its aquisition, I had the ring and pinion changed from the stock 3.02-1 ratio to a lower 3.22-1. The torque converter used was built to specs provided by a Chrysler torque-converter expert, and I acquired a flywheel to attach this new 4-bolt converter to my existing 6-bolt crankshaft flange and 3-bolt converter. (Note '84s used a 6-bolt crank flange and 3-bolt converter; newer vehicles have an 8-bolt crank flange and a 4-bolt converter.) The transaxles for 1987 and later turbocharged Chrysler cars drive through stronger axle shafts, so these too were replaced.

Installation of the new, larger drive axle (left) led to a previously impossible condition: wheelspin!

New intermediate shaft (top) replaced the original, smaller piece.

Installation of the new transaxle was a six-hour job that went relatively smoothly. After completion, a few trips around the block confirmed what I had hoped for. My Dodge 600 was now capable of wheelspin from a slow roll- something that was not possible before the transaxle change. Before my next drag strip test, I installed a 3 inch air duct from below the front valance to the air box in order to provide an ample supply of cold air. I again mixed the fuel to obtain sufficient octane. My first run surprised even me with a 15.31 at 88.9 mph. The transaxle had obviously made a great improvement in bottom end performance, because now I was fighting wheelspin. Later in the evening I had back-to-back runs of 15.17 at 90 mph, and it was obvious 14-second elapsed times were only a quicker start away. Horsepower was calculated to be about 170, an overall improvement of 43 so far. After about 4000 miles and 50 passes at the strip, I began to notice a buzzing noise from the converter area. I pulled the transaxle and had the converter cut apart, and it's here that the damage was found. I had wiped out the thrust washer assembly that takes all the load during high stall conditions.

Special torque converter was built to specs provided by a Chrysler torque converter specialist. Two failed thrust washers are at center.

I settled on a new torque converter sold by Turbo-Action (as well as Mopar Performance) that has needle bearings instead of the bronze and babbit thrust washers. It is slightly tighter than the factory unit I had installed with the heavier duty transaxle. The new converter required a few modifications before I could install it. The early transaxle that it was designed for used an oil pump that has a drive gear with two tabs in its inside diameter, which the converter hub engages. My later-transaxle oil pump has two flats on its i.d., so I had to have a machine shop mill corresponding flats on the hub of my new converter. This converter has three mounting bolts, so the original 3-bolt flywheel was reinstalled. The Top Dead Center mark was also made more obvious (2.2s are timed through a hole in the bellhousing by a mark machined on the converter). Back at the strip, it appeared that the tighter converter was exactly what I needed to kill some of the 2.2s low end torque. Best time of the day was a 15.05 at a slightly slower 89.0 mph. I still, however, could not get into the 14s. My only hope was to find more horsepower. My Logic Module already was running the engine with maximum boost, fuel and timing. Luckily, I stumbled across a rather devious but very intelligent auto-oriented computer head who fabricated a new chip for my existing module. This one would allow as high as 14 psi of boost; however, my stock injectors are only safe up to about 12 psi. I set the boost at 11.5 via various tuned bleed-off orifices and went back to the strip. First run success finally arrived with a timeslip that read 14.96 at 90.0 mph. After a couple more runs, I stopped with a best time of 14.77 at 90.7 mph. The last race for me in 1988 was our Second Annual Mopar Day at Kansas City International Raceway on October 16. The weather was good, with the temperature at 80 degrees, relative humidity at 35 percent and the barometer at 29.98. Since the new Logic Module chip would allow temporary overboost, I opened the exhaust system. (The other modules had only minimal tolerance for overboost, and opening the exhaust would consistently let the turbo spin up quicker than the wastegate could control. This generally cause the overboost condition.) This was going to be a good day to compare the performance of my '80s FWD musclecar with the '60s and '70s Mopar RWD musclecars. The initial run was an exciting 14.48 at 93.9 mph. Horsepower calculated to about 192; the new devious box combined with open exhaust increased the power another 22 hp, but lowering the boost put it back to a safer 182. Subsequent runs were all between 14.47 and 14.51. As the day progressed, it appeared that my injectors were not supplying the fuel, so I lowered the boost slightly and dialed the car in on a 14.60, and the mph stabilized at 92.0. I let a very good (and consistent) friend drive the 600 in the bracket race, and he piloted it to a runner up finish in the 13.00 to 14.99 class. Who would have thought that an '84 Dodge 600 four-cylinder would be at the strip, much less competing the same class with just about every other factory Mopar musclecar ever made?

PHASE FOUR

After the 14.40s, I finally was as far as I figured I could get with my existing non-intercooled 2.2 setup. However, I couldn't stop at 93 or 94 mph. A few more calculations showed 98 mph was in reach, with only 200 hp needed to get there. My injectors would not support the 200 hp attempt, and without nitrous oxide I knew I was at the end of my road. But luck would again go my way, as I was able to purchase a complete intercooler manifold, intercooler and all the associated hardware needed to adapt it to my vehicle. The first step was to disassemble my old hardware, While the head was off, I checked and cleaned the valves and installed new valve seats. I also drilled and tapped the block for the new 11 mm head bolts that give the much-needed clamping power. The new intake I installed was a two-piece tuned unit that changed the torque peak to a lower rpm level--just exactly what my automatic-equipped 600 needed. While it was off the car, I also matched the two halves of the intake to the gasket, therefore matching the runners, much like one would match the intake to the heads on a V8.

Intercooler (arrow) was borrowed from an '87 Daytona and instantly improved ET and mph in the quarter mile.

Surprisingly, everything bolted on my 1984 600 K-Body, even though it was intended for an '87 G-Body (Daytona). I did, however, have a number of items that needed to be modified and/or removed. Initially the new throttle body was a big problem. However, my advisor in this new project engineered an aluminum sleeve that let my old 1984 motor-driven "valve" idle motor fit onto the new throttle body, which originally used a motor that pushed a plunger in and out of the orifice in the body. Right after I thought things were solved with the throttle body-idle motor problem, I realized the hood would not shut, as the water drain trough sits on top of the new tuned intake. I left the room as my dad used his metal cutters to trim off the offending sheetmetal. I guess this is how people feel when they cut holes in their hoods to clear blowers and carburetors.
My old radiator had two additional parts that the new intercooler radiator assmebly didn't. One was a hose nipple that was the return for the heater hose, and the second was a female pipe fitting that accepted the radiator fan thermostat switch-sensor. I bought a 4 inch long piece of 1.5 inch diameter pipe and welded on the correct size nipple for the heater hose and the female pipe fitting to accept the thermostat switch-sensor. I had to buy an '87 Turbo II Daytona lower radiator hose and use the smaller diameter section of it on one side of my new 1.25 inch adapter. Then I cut my old hose and attached it to the other side of the adapter. Software problems always surface with computerized items, and this project was no exception. However, my devious but auto-oriented computer head friend corrected my Logic Module to feed the new high-flowing injectors and allow for the 100 degree of (average) temperature drop air that the intercooler would provide.

Opening in old idle motor connects to a custom-fabricated aluminum sleeve.