High powered ignition systems are generally needed when engines are highly modified.
Typical examples are the addition of Turbo-Charging systems or Nitrous Oxide systems. Both
of these systems produce very high combustive pressures and dense mixtures. The stock
ignition doesn't produce high enough voltage and amperage to reliably ignite the mixture.
Also with high performance cams which allow higher RPMs, the stock ignition starts to fall
off at the higher revs.
For stock setups and mild modifications such as custom exhausts, high flow air intakes, and modified ECUs, adding a high powered ignition system will not get you more horse power. The stock ignition system is more then ample.
I would agree and disagree with RogoMan. The Nissan stock ignition works well with bolt ons, but an upgraded ignition system is a big improvement. I would recommend MSD 6A with rev limiter, MSD Blaster SS Coil, and your own choice of 8.5 ignition wires, I would recommend Magnecor. An MSD ignition system would improve power, quicken throttle responce, smooths out idle and starting, reduce spark plug fouling, improve mileage, and reduce emissions. MSD has ignition setups for different applications, from an all stock vehicle to all out racing and everything in between. I would recommend it to anybody at/in any stage of vehicle performance.
89 Nissan 240SX SE
MSD 6a Ignition Tips
Before you put it on make sure you have the Tach adaptor from MSD first. It's Part # 8910. If you dont have this your Tach will stop working when you put the MSD box in. I will tell you how to hook it up.
The wires /terminals you need to cut will be found underneath the stock coil wrapped in heavy electrical tape.Take/cut the two wires that originally went to the coil make sure you leave some wire sticking out of the coil still, like an inch or so ( green/negative and black or sometimes red/positive ), connect the negative ( green ) to the white wire from the box, connect the positive ( red or black ) to the THIN red wire ( not the one for the 12v source ) from the box. Now you you're done with that side, now turn to the coil where you left some wire still sticking out ( I hope , hehe ). Take the orange wire from the box and connect it to the positive terminal ( the black or sometimes red wire, where you just cut to connect the red wire from the box ) of the coil. Take the thin black wire and connect it to the negative terminal ( the green wire, where you just cut to connect the white wire from the box ) of the coil.
The THICK red and blackwires are the 12v source. Just connect the thick red wire to the battery and the thick black to any good source of ground. Basically what you're doing is putting the box in between the wire you just cut going to the coil.
Now for the Tach adaptor, you need to to tap this on the original green and black (or sometimes red ) wires, the ones you cut to connect the thin red and white wire, remember?. You need to connect the adaptor wire at the white/green and red/black (or red) connectoin side before the box, not the wires from the box to the coil. It does'nt matter which wire goes to which from the adaptor.
Hope you enjoy it :-) . Later....