In my quest to reduce smelly emissions and improve fuel efficiency I was thinking about Fuel Injection and several here said upgrade ignition and tune carb first. Well tuning carb got me part way there, now I have finished the TR upgrade and it is looking good so far. Here is my story.
75 CJ5 304 V8 Prestolite Stock Ignition MC2100 Carb Manual Tran.
After lots of research on the off-road.com Jeep Short Wheelbase BBS I decided on the TFI HEI hybrid approach:
All from Advance Auto Parts
Replace Prestolit Distibutor from 80 Wagoneer 360V8 with Duraspark Distributor from 85 Ford F150 5.8L V8
Cap Adaptor GPSorenson FR110
Cap GPSorenson FR131
Rotor GPSorenson FR107
Coil GPSorenson 407S ..(Look at pictures get the square one)
Plug Wires Autolite 86262 ..from 80 Camaro w 350 V8
Ignition Module GPs. EL102
After reading all the questions about resistor wires and voltages, I just decided the GM HEI hybrid was the easiest path to the Highest energy system. I still have not opened up my plug gap and have only run it long enough to go out of the garage and back in, but I can already tell a difference!
Started with the ignition module. They are normally inside the distributor, so I had to fab a mount. Took an old PC processor heat sink and drilled a couple holes and mounted the module to it with heat sink compound (not dielecric grease). Didn't care about the ground thru the mount since I was going to run a separate ground wire. Then I attached the heat sink to a couple angles to give a mounting base. Here are some pics of other's setups.
Here is a good pic of hooking to the duraspark distributor:
Next I fabbed the harness (basically 5 #16 hookup wires, Red, Green, White, Yellow, Black). The module uses 3 .25 (1/4)female quick connects and 1 .187 (3/16) I used this diagram that I found at HEI Info NOTE: you have to read the text for what goes where on the module. B goes to Coil +, C goes to Coil -, W goes to orange on dizzy, G goes to purple on dizzy, Black is grounded to the mounting screw (and I ran a dedicated ground to this also). Here is my coded diagram:
Next I swapped the distributor. Couple of tips I read and will pass along: Make sure to mark the position of #1 wire and the position of the rotor. Use tape on hoses or belts to make it easy. It seems the important thing is the angle between #1 and the rotor, since the new distributor had a different rotor position, so I just moved the number one to match the angle between and all was well. There is a good writeup on this site: Distribtor install Also put it in neutral and chock the wheels so the engine doesnt get moved by the vehicle. Also, some of the rebuild distributors do not have a locator tab, so the #1 could be 180 out of phase if you aren't careful. #1 should be right by the vacuum advance. Here are some pics from that site, starting with prestolite, rotor position, install of duraspark.
Next was the coil. Basically I just cut the existing bracket and drilled a couple of holes to mount the coil. Orientation is not critical so I laid it on its side.
Module on Heat sink inside of right front fender and Big Distributor Cap:
Closeup of module on heatsink:
Next fed the harness from module to dizzy to ignition power tucked away in existing wiring looms. Basically there is only one power and one ground connection that is external to the ignition. See the diagram in the HEI link above. As noted, I ran a dedicated ground for the module instead of relying on the mounting screws for a ground.
Next the plug wires. Here was my first screwup (didnt read enough). Quick glance at the hanes book showed #1 #8 right next to each other and I assumed the rest were 234567 around CCW. WRONG! As all you experienced wrenches know there is a firing order and that is the order of the wires (duh!). Anyway I mounted them, cleared out tools and the last of the prestocrap from the engine bay and got set for first crank.
Woohoo! at least it popped and snorted a bit! Tried moving dist. back and forth figuring timing was off, just got worse. Then I spotted the plug wire foul up by reading the book more carefully. Rearranged the plug wires in the correct order and she cranked like r-r-vooom!!!! Wow! never had it fire off that quick. Also would idle right away! Used to be you had to dance on the throttle a bit for the first minute or so till it was warmed up.
1st Test drive report:
Big difference. Started right up r-r-voom! didnt even have to play throttle games (used to be pump, pump, hold 1/3 down, crank r-r-r-r-r-r-r-rumble-snort-r-r-voom!) Idled smoother, didnt require fast idle to stay alive.
Once warmed on the road, acceleration and throttle response smoother and snappier. Idle smoother and faster (had to back off the curb idle to get back to 700) Stop and go for 40 min running erands and module barely warm to touch. Heat sink must be working good. Will check when it is warmer out (about 70f here now).
Update a few days later.
Swapped in new champion RN14Y (stock plugs) and gapped them at .045. Further improvement in zip and starting, but not as dramatic as the initial jump in performance.
John Shufflebarger (shuffjb)