Dodge Caravan - 4 cylinder, FWD, "K-car" design
2.2/2.5 engines with burned-out electronics and
associated wiring need not go to the salvage yards. You can completely scrap out the original electronic ignition
system with the integrated computer boards and go for the traditional points
"Kettering" distributor. I
have successfully done this ignition mod on my 1984 Dodge Caravan with a stock
2.2 ltr. motor. This mod is uses the same distributors found in old,
air-cooled VW engines which are fired by Bosch 009-type centrifugal-advance
distributors. New Bosch units can be
purchased in the $60 dollar range. With
minor mods, this distro can be swapped out and installed on the 4-cylinder 2.2
K-car.
To
make the 009 fit in your 2.2 motor, you have to replace the stock 009
distributor drive cog with the stock K-car's cog, both of which are fixed in a
similar fashion to their respective shafts with a securing pin at the bottom of
the shaft. The stock drive cog on the stock K-car distributor does not
have the off-set in the cog, which the VWs do have, so you have to use the
K-car distributor-drive cog on the 009 distributor before installing the 009 in
the K-car motor.
If you want to go back to the "Hall effect" ignition, you can install 'permatune' or 'Compufire' kits for the 009 which eliminates the points, so you'll be modifying it again to resemble the stock Caravan distributor that you just removed.
Of course, you need to reset the timing position for TDC as the stock location on the 009 will not match the TDC mark on the K-car pulley. A no-brainer, really. Just play with the distributor positions until you get the timing and firing order right. Note: firing order for the 4-banger K cars are 1-3-4-2. VW timing order is 1-4-3-2.
I haven't measured the total advance with the 009 on the 2.2 motor, my guess is that it is not adequate, but my stock 2.2 motor, a 1984 Dodge Caravan SE, can do 75 mph in 5th gear on the freeway with the Bosch/VW unit, that's good enough for me, but a better advance curve should get it rev'ing past that speed. You could consider the Bosch 050, which has a slightly-better advance on it. Or maybe the vacuum-advance 205, which will have a even more advance, but the vacuum unit may present clearance problems on the 2.2/2.5 motors.
First I found it was very easy to use a punch to knock out securing pin in the K-car distributor, but the VW securing pin is always much tighter and it requires a lot more work. A good bench vise is necessary. See photo: http://www.geocities.com/ngant17/Vwdist1.jpg
Once you take the cogs off, you have to also know that there's a slight difference in the diameter of the VW and K-car distributor-drive shafts. See picture, bosch009 & caravan distributor compared: http://www.geocities.com/ngant17/bosch1.jpg
The 009 shaft (shown on right of picture) has a bigger O.D., which means you have to slightly ream out the I.D. of the K-car's distributor-drive cog in order to get it to fit on the VW drive shaft. You can see the K-car drive cog in the center of photo. I reamed it out with a high-speed 'Dremel' type of rotary grinder. See this photo: http://www.geocities.com/ngant17/Vwdist2.jpg
Pay attention to the K-car's drive cog, as shown in the previous picture. You can see it has a shoulder on top (the VW distributors don't have the shoulders), so it must be completely ground down as the securing pin will not line up with the hole on the 009 distributor drive shaft. In fact, you will have to grind down more than that, as once you reinstall the shim(s) between the drive shaft and the cog, you will need to have little bit of play here or the drive shaft will not spin freely. See photo of the initial grinding operation: http://www.geocities.com/ngant17/Vwdist3.jpg
Once you reamed out the ID and you've ground off the shoulder and sufficient metal on the flat, go ahead and mount the K-car cog to the VW distributor-drive shaft. Once you get the securing pin in (use the original K-car pin, not the Bosch pin from the VW distributor), check to make sure the shaft spins easily. If it doesn't , it means you haven't ground down enough of the surface metal, so you will have to take off the cog again and grind down some more metal to compensate for it.
The stock electronic Chrysler distributor which is removed, it is typically connected to a electric solenoid in the Holley carb to create a feedback circuit (note: the Holley 5200 series carbs are "non feedback" while the 6200's are "feedback"). You can slap on a VW Brazilian-made "progressive" carb, the bolt-pattern will fit the stock 2.2 intake manifold, but you have to customize the linkage for the accelerator cable. I prefer this carb as it's more miserly on gas.
Finally you will need to toss the stock K-car ign. wiring set and use stock or aftermarket VW ignition wires and spark plugs, as the stock K-car ignition wires won't fit the VW distributor cap. NGK Iridiums, anyone? Also, the short HT wire for the VW set to the coil will not be long enough to reach the stock location of the K-car's ignition coil, so you will have to mount the ignition coil closer to the VW distributor.
One last and quite important note: the flimsy VW distributor drive clamp will work, although you must drill an new 5/16" hole, offset approx 1/8 inch from the stock hole location on the clamp. It is highly recommended that you use the newer, heavy-duty (billet aluminum) distributor clamps that EMPI, Bugpack and others are selling. These are much stronger and they won't crack! Check your local VW bug or import shop for this part (ebay has them, too). Otherwise the OEM VW distributor clamp will eventually stress out and break, as mine did, leaving me temporarily stranded until I replaced it. The stock VW clamps just weren't designed for the more powerful K-car motors! In addition, you might need a washer or two to mount under the VW clamp so it can be properly secured to the K-car engine block.
http://www.geocities.com/ngant17/Bosch009_mounted.JPG
