Ignition Upgrade
Ignition Upgrade
- Thread starter WAXER
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Cheepjeep85
Crazy Sr. Respected Jeeper
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once you get the hei you can simplify it all in a big way by powering the dist off of the solenoid, 1 wire, 1 foot long, then a new tach wire is all you'll need. you can then remove all of the factory ign. stuff, and not worry about the resistor. another small benefit of powering the dist from the solenoid is it has a more direct line to the battery, offering less resistance and possibly better spark.
WAXER
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Just ordered the ebay HEI. I was looking for a new tach just to make things easier and less messy. Sounds like I'll go off the solenoid and be done with it. I'll post when my dist arrives. Thanks everyone!
Cheepjeep85
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i'm not for sure how the factory tach is wired, i didn't have one factory, but you can find out if you have a meter. it should still have the same basic 4 wires although they may be different colors, you can use the meter to find out which wire is which. once you find the pos, neg, and back light wire, the only wire that should be left is the tach wire. if it were mine i would still pull another wire from the tach to the dist. that way you can remove the factory ign. wiring without having to worry about removing the tach wire with it.
73CJ
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On the HEI distributor cap there should be a marking for the "TAC" or "TACH" wire.
You will have to splice into the wire. I have used a used a crimp connector like this:
This crimp connector wont cut the original wire.
The 3M connector can cut the wire and isn't waterproof. After a few years they can corrode. They are quick, but can be a pain later.
Pickup the right connector at NAPA or the junk yard and put on new spade terminals.
neverdone
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Just got my HEI distributor today looking forward to getting rid of the points and maybe better gas mileage got the distributor and tach pigtail and 12volt pigtail with a wires also for $170 shipping and all from 4wdrive hardware
IOPort51
NOT the voice of reason Jeep-CJ.com
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4.2 W/MC2100 carb, 4.0 head W/3 angle valves,SS Header,TFI ignition with MSB-6 offroad module,CS144 140 amp RPS alternator with remote regulator T-150,d-20,Dana 44 with OX lock and disk brakes. D-30 with Spartin locker,
skyjacker 2.5 lift?nitro shocks,31" BFG A/T off road.8000 lb Warn winch, original owner.=^)
2006 Toyota Tacoma
I run a stock 1979 jeep dizzy with a ford cap, rotor, and adaptor with the jeep ECM and a TFI coil. Off the shelf parts, less expensive, no questions about drive gears,
, and some say it works better. I don't have a dyno so I can't make any such claim.
, and some say it works better. I don't have a dyno so I can't make any such claim.
Rescue Diver
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Since you have a AMC 258 i6 / 4.2l and you bought it from a manufacturer that set it up specifically for the I-6 with what should be the correct gear, you shouldn't have to worry about the drive gear. It looks as if some people have had problems with HEIs that bought them from a junk yard, converted them for AMC 258 i6 / 4.2l and put the wrong drive gear on them from the later model ford ignition. Some people with V8 motors also had problems because the V8 has a soft cam gear that won't last when mated to a hardened distributor gear. The great thing about Jeeps is they're popular, so people have come up with a lot of different options for distributors. Is any one distributor the best choice? No not really. I personally prefer the HEI because they're a much simpler design they don't require a lot of clutter and extra wires under the hood, they're easy to tune, and they make more than enough spark for a AMC 258 i6 / 4.2l . Around here, distributors and Carburetors seem to invoke a bigger rivalry than Chevy vs. Ford at the drag strip! Just feel safe in knowing that the choice you made is being used by lots of people on this forum with good results. Just like with any distributor, make sure the timing is set correctly. Not just the initial 10 degrees or so, but the total timing as well(initial, vaccum, and mechanical). Ive found that 34 degrees of total timing works well with my combo of a AMC 258 i6 / 4.2l with a 4.0 head and a stock cam. Yours might need a little more or less. Just set the total timing with as much advance as it'll take without pinging or having hard to turn over starts. Good luck!
