Don't screw with it. Use the OE NGK Platinum plugs and you are fine. Too many people have tried MSD, Trust, Jacobs, Nology, Torquemaster, Splitfire, HKS etc and have come back saying nothing happened or something got worse. The factory ignition is excellent, there is no real improvement to be gained by using something else. Nology wires are prone to producing too much RF and interfering with the ECU, HKS stuff was known to burn out coils, Torquemaster and Split fire dot work as well as they claim in the SR20 engine. Jacobs is just plain crap for the SR20. MSD and Crane are two systems that are more trouble than they are worth because the parts are big and there are no plug in applications that I am aware of, you have to hack apart your stock system. Save your money for other things.
Lately with high horsepower applications from turbos, like in the range of 250-320hp the stock NGK Plat. plugs still work fine but they need to be gapped smaller. With the stock gap the engine will hesitate and stumble a little, closing the gap fixes the problem.
With my 100 HP JWT nitrous system the stock ignition seems to handle the power quite well, I get no hesitations, stumbling or anything else weird. I am only putting out about 230-240HP with the nitrous, so I haven't reached the big boys yet, although I am starting to run 1/4 times with em ;)
Spark plug heat ratings:
What's a heat rating you ask? Check out NGK's web Site for more info.
More on Aftermarket Ignition Systems
Comments by Dan Thompson
For the most part, the ignition systems in most Japanese cars are MORE than adequate and are more than able to supply enough voltage to fire the spark plugs on stock or mildly modified cars (intake and exhaust). About the only time you're going to need to upgrade your ignition system is if you increase cylinder pressure (through turbocharging, supercharging, Nitrous or increased compression), use a fuel that's more difficult to ignite than gasoline or run the engine outside of the RPM band the ignition system was designed for (go above 8000 rpm regularly on our cars).
I have a sneaky suspicion that the "gains" advertised by Jacobs were obtained by replacing worn-out ignition system parts (cap, rotor, plugs & wires) with new parts and/or their "high performance" parts. You'd probably see the same gain from a good tune-up.
Turbo magazine ran a test on a Jacob's Omni-Magnum system in a lightly modded Civic and found a slight (1hp) gain on the low-end but a reduction in power on the top-end. When they hit the engine with a shot of NOS the Jacob's system was good for 1 to 4hp over the stock system. Definitely not a big gain for the money.
A Mustang magazine ran a test on a Jacob's Omni-Pac awhile back. They did some 1/4 mile runs before and after the install. They found that the car actually slowed down with the system installed. Their reasoning? By opening the plug out to the gap setting recommended by Jacobs the spark became too powerful. The shockwave created by the force of the spark jumping the gap actually "pushed" the A/F mixture away from the spark, causing a misfire for that particular power stroke. Closing the plug gap down to the point where misfire was eliminated showed no improvement in the 1/4 mile in comparison to the stock system.
So, for you guys who AREN'T running forced induction, NOS, or Nitro Methane, take the money you're gonna spend on that ignition system and buy a header. You'll see a bigger gain.
Comments by Carson M. Hanrahan
> I called Jacobs & for $319 limited time offer I
> could get 10-12% more low-mid torque, [...etc...]
They're full of shit. I tried the Jacobs ignition - over 6 weeks, in fact. It was a bitch to install and then they wanted me to *tweak* the friggin' thing to have it wring out the claimed horsepower - change to normal plugs, screw with gaps (they even suggested I index the plugs), adjust timing 'till I could see the marks in my sleep, etc.
All this took about 6 weeks as I only had the weekends to work on it. Finally I said screw it and called them again to send it back and get my money back. They flat-out refused - claiming I was past my 30 days. I tried to remain calm but eventually blew up.
The damn thing didn't add a single horsepower to the car - I dynoed it and had the sheets to prove it. Even then, they wouldn't take the shit back, claiming I hadn't done enough tweaking to get it to work.
Yes, I too was suckered in by their claims and, thinking the guarantee meant something, though I had nothing to lose. Wrong.
Run, don't walk, away from that company and their deceptive practices, false claims and piss-poor customer service.
BTW, I eventually ended up "passing the suckering buck" to some poor Mopar owner and sold the Jacobs kit for more than I bought it for. =:-)
Comments by Kurt Sussman
> Just thought some of you might find this interesting. I sold a Jacobs ignition
> system to some guy and he said he was able to run almost half a second
> faster at the quarter mile using it on his Integra GS-R. And I thought that
> these things dont work!
If you read Dr. Jacobs' book, he says in there that there is nothing better than the Nissan factory ignition until you get over about 8000 rpm. Lots of racers use the Nissan crank trigger to run the ignition on the big American iron. Before you ask, we don't get that in the US except on the 300zx TT. Whoops, we don't get that any more either...
I agree with Kit; this is interesting only to people who don't have Nissans (or other late-model Japanese cars; they all buy ignition components from the same manufacturers).
But it *is* interesting that it made a difference on a Honda; maybe that's another area where Nissans are dramatically superior, or maybe that guy just never put new plugs in before he bought the Jacobs kit.
More on Spark Plug Wires
Comments by Frank Pelliccio
I recently decided to tune-up my '93 NX2000: new plugs, wires, clean and oil the K&N, etc...I stopped-in at a local Pep Boys to pick up the gear. Everything was fine...until about a week later. I was driving home from work, and was exiting the highway...When, suddenly, my car died. It stopped accelerating, and wouldn't respond to the gas. It turned out the $80 plug wires I had put in the car were...umm...garbage. The wire going from the distibutor cap to the coil had melted [also melting the recepticle in the cap]. I was speaking to a mechanic friend about the incident and he explained to me that in his experience, most Japanese cars [particularly Nissans and Hondas] really require true OEM parts. Perhaps this is common knowledge to some of you, but for me, it was a $200 mistake. [Ed note: I wouldn't say our cars require OEM parts; NGK and Nology wires work fine. It is more likely that the Pep Boys wires Frank bought were garbage. -MM]