Yesterday I swapped in all new igniton components amongst other items in preparation to get my car smogged at the new STAR station.
A little background on the car first: 88GT 5spd, 290,000 miles on original engine and trans. I have owned the car for four years and put almost 60,000 miles on it doing a 170 mile/day round trip commute of which about 80% is highway miles (the I-15 superspeedway). Right after I got the car I pulled the engine and replaced every gasket in the engine except the head gaskets, replaced timing chain and water pump. New Bosch 7mm wires, E3 spark plugs but otherwise stock ignition system. In fact I would say the entire engine is factory stock. I've never had the heads off but compression when I pulled the engine was all cylinders around 150 psi. I did notice maybe a 1mpg difference with the E3 plugs. OK, so the car has been running pretty well up until the last few months: my tach started being erratic and bouncy and below 1500 rpm the engine would buck and hesitate in any gear.
So yesterday I finally swap in the brand new, not remanufactured Cardone select distributor, Taylor Thundervolt 8.2mm wires, NGK UR5 plugs gapped to .045" and MSD Blaster coil. I set the timing at 10* with the engine in diagnostic mode. Upon first drive, the idle is smooth, the bucking and hesitation below 1500rpm is gone, it now pulls smoothly at any RPM in any gear and as an added bonus, my tach is now steady and smooth.
Some things I noticed when I was removing the original components: the stock coil had grayish, powdery residue on both sides of the steel frame between the sealed coil windings and the steel frame, like it was arcing through the insulation. Also, the connectors were a loose fit on to the coil whereas the MSD coil connectors fit very tightly and have excellent retention. Another thing I noticed: my Bosch 7mm wires were trashed; lots of evidence of leakage through the insulation and two of the connectors broke off at the plug when I pulled them. The E3 plugs looked OK for having 50K miles on them. They are not gappable, they are set in manufacturing. I have no complaints about them, they did look like they gained a bit of MPG for me but I wanted to try conventional copper plugs with the hotter MSD coil and excellent wires after reading all of the posts and experience of other members with the NGK plugs and the tests about various ignition setups effect on mileage and power.
The reason I decided to go with the Cardone distributor over replacing the components was this: I wanted to replace the ICM, cap/rotor and pick up coil in my stock distributor. After pricing the individual components versus the NEW Cardone select, there was only a few dollars difference and for that you get all new components, not remanufactured, brass insert cap and rotor, the newer star style induction pickup versus the old "rusty fork" I had and being new, no worn out, sloppy shaft play. The new dizzy came assembled with heat sink compound but just to make sure I pulled the ICM, cleaned all surfaces and installed new electronics grade thermal compound. Here are some pictures of the old versus new dizzys:
I know the new ICM is not a GM original so we'll see how the aftermarket one lasts. i will keep the GM original as a backup if needed. Finally, I don't know how much longer the original pick up coil would have lasted as the plastic connector broke quite easily when I tried to remove it and the sealing tape around the coiled wire was all dried out.
Only thing left now is to change the oil and filter today, drive it around a bit to get it hot and then take it to the STAR smog station for testing, I will post my results after I get them, Wish me luck!