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MSD Spitfire Ignition

TiRod

NAXJA Forum User
Location
SW MO
It's been out for a year. Has anyone installed one, and does anyone have an opinion?

CD ignitions aren't the highest priority on our modding list - but some of us have XJ's getting long in the tooth. Blowby, oil consumption, and fading power over the years takes it's toll on our enjoyment - and the rebuild for a stroker isn't economically justified yet.

So, would a multiple spark help at all -or is the price to perk up the driveability too steep for the results? That's a question I'd like answered by someone who has installed it and knows what they got out of it.

It doesn't help I get a nice discount at work - and a pay plan. On the other hand, I'm trying to balance it with stuff we could all use - like Speedway's dial fan adjuster that hooks to the gauge sender. Very slick, automatic control, manual full on for crawling, etc. I think most of us could use that.

And to keep us from drifting to Street performance, what could the CD ignitions do for us on the trail?
 
well first you need to limit yourself to those that are waterproof. does someone know which ones are
 
A very good point - and debatable. The wiring harness on the XJ series is no more waterproof than the average soccer mom van - it's built with the exact same wire and connections, in the same ways.

A good two day soaking in Katrinaville will total it. Why Jeeper's think they are impervious to water damage doesn't bear out with the hundreds of posts by young drivers who mud their XJ's and get stuck. After extraction, it all comes out - not only the fluid changes, but the won't start, won't run, won't shift right, won't won't won't.

Waterproofness is a great topic for advanced off roaders - they kind of people who know they can die crossing a swift moving creek. Most of us don't even try.

On the other hand, a lot of electronics will work fine after the occasional dunking IF we would let them dry COMPLETELY. Off roaders aren't prone to that, they're out 25 miles from the nearest paved road and the weekend is running out.

The Spitfire isn't waterproof, and for most of our purposes, neither are our XJ's. Let's move on.

Comments about actual performance on the ignition?
 
I am also interested in hearing other peoples opinions about ignition upgrades. My 91's engine is old and tired so I have been thinking about an MSD-6A or something.
 
I run the MSD 8228 coil and 32239 plug wire set. This combo really pepped up the engine. Much smoother idle, throttle response is very quick and no excessive crank over for start up. This has by far been the best noticeable upgrade to my 13 year old motor. The coil is a direct plug in replacement, no extra wires to hook up.
 
I have limited knowledge about after market ignition systems, and none about the one you're asking about, so this comment is FWIW. I know people who have installed after market ignition systems over the years on their XJ, and most, if not all, removed them. The stock ignition module/coil puts out a ton of volts, as do all late model EFI systems, so it's very difficult to improve on the stock system. As far as improving stock engine programming, this can be tough also. We installed a Jet Performance programmed Renix computer when testing for the King of the Hammers race, and lost 2 mph top speed over the stock computer. Conditions were identical because we swaped the computers on the lake bed where we were testing and made multiple back to back runs.

My point is that as far as prioritizing funds for modifications, changing engine control parts can be at the bottom of the list.
 
I have limited knowledge about after market ignition systems, and none about the one you're asking about, so this comment is FWIW. I know people who have installed after market ignition systems over the years on their XJ, and most, if not all, removed them. The stock ignition module/coil puts out a ton of volts, as do all late model EFI systems, so it's very difficult to improve on the stock system. As far as improving stock engine programming, this can be tough also. We installed a Jet Performance programmed Renix computer when testing for the King of the Hammers race, and lost 2 mph top speed over the stock computer. Conditions were identical because we swaped the computers on the lake bed where we were testing and made multiple back to back runs.

My point is that as far as prioritizing funds for modifications, changing engine control parts can be at the bottom of the list.

i had no idea jet made a renix computer. i know mopar performance did and i almost bought one, just becasue it was so rare but never did since i had no idea what they actually did over stock.

i found this thread http://www.naxja.org/forum/showthread.php?t=16630
 
Why Jeeper's think they are impervious to water damage doesn't bear out with the hundreds of posts by young drivers who mud their XJ's and get stuck. After extraction, it all comes out - not only the fluid changes, but the won't start, won't run, won't shift right, won't won't won't.

...
On the other hand, a lot of electronics will work fine after the occasional dunking IF we would let them dry COMPLETELY. Off roaders aren't prone to that, they're out 25 miles from the nearest paved road and the weekend is running out.

While I don't disagree about waterproofing things are important I will say I've never had any water get in my diffs, or ever not start, or shift incorrectly. When younger, I played in the mud more. I've flooded the interior twice, with the fuse panel and speakers on the passenger side being completely submerged in muddy water for just under 10 minutes one time, and other electronics 20 minutes another. I have not had any shortages, anything not work, any water in any fluid, and no problems with it period.

Those were over 3 years ago now, one of those stucks was actually in a magazine for top reader's stucks. Also, not once have I stopped and let it dry out. Drove on the rest of the trail, then the 1 drive home.
 
I have an MSD street fire ignition mounted on the inner fender right next to my battery. I haven't had any problems with water, only connection problems on my old battery terminals.
EDIT: As far as actual performance increases go, there really is none. because you still have to use your stock coil holder, so its basicly like an amplifier. I wanted it to try to solve other problems i was having. BUT the rev limiter is kinda fun to set really low :laugh3:
 
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I have limited knowledge about after market ignition systems, and none about the one you're asking about, so this comment is FWIW. I know people who have installed after market ignition systems over the years on their XJ, and most, if not all, removed them. The stock ignition module/coil puts out a ton of volts, as do all late model EFI systems, so it's very difficult to improve on the stock system. As far as improving stock engine programming, this can be tough also. We installed a Jet Performance programmed Renix computer when testing for the King of the Hammers race, and lost 2 mph top speed over the stock computer. Conditions were identical because we swaped the computers on the lake bed where we were testing and made multiple back to back runs.

My point is that as far as prioritizing funds for modifications, changing engine control parts can be at the bottom of the list.
X2, stock ignition does a fine job. It is money poorly spent to try to upgrade IMHO.
 
MSD has done a great job of marketing the multiple spark concept, and hasn't done it alone. Is it possible the factory caught up - even with 90's technology - to the point that a great factory ignition doesn't need much improvement. I see and read the same on Chevy forums about the HEI, and Ford, too.

Perhaps a lot of the performance increase was in comparison to stock dual point distributors of the sixties. Most racers moved to CD igntions as soon as they could back then - and the muscle car mavens let it out as a secret power producer. Smokey Yunick has it in his Power Secrets book, among others.

How many of us could justify a MSD 6A against the performance increase of a lunchbox locker? The real secret to performance improvement is choosing the right mod because it gives more for the money.
 
IMHO, if the spark ignites the air/fuel mixture, nothing better can happen. Multiple fuses on dynomite will not create more power, as long as the one you have ignited it. Hotter spark does not equal more power.
 
I was given an old Malory Hyfire for free last year. This went into my 84 porsche (R.I.P.) for awhile.

I really didn't notice any improvement in power, but the old gal sure idled a lot better.

I'll be putting it in my XJ as soon as I get one.
 
IMHO, if the spark ignites the air/fuel mixture, nothing better can happen. Multiple fuses on dynomite will not create more power, as long as the one you have ignited it. Hotter spark does not equal more power.

multi-spark burns cleaner and more efficient because one spark doesn't always burn all the fuel in the chamber
 
Its been said before.Some vehicles are better suited with after market ignitions.Xj's in general are not.
I have noticeable increasesin the ass dino using champion truck plugs over the factory recommended plugs,along with msd wires.....screw after market ignition sys.

before you go out and spend money on a aftermarket igntion sys. try a set of champion truck plugs and good wires......the difference amazed me!!!
My 89 always seemed to take too long to wind up and I wrote it off as having a led ass due to all of the armor and big tires........after I put the plugs and wires on it made a big difference.
 
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Do 'champion truck plugs' have a number? When one walks into a parts store what do one ask for?
 
its not to often I walk into a part store with are part number. I usually just tell them the year make and model I'm working on and then what part I need. so if you tell them you have a 96 jeep Cherokee 4x4 4.0, and you want champion truck series spark plug you would probably find what you are looking for. I have had the best luck getting them at advance auto
 
Its been said before.Some vehicles are better suited with after market ignitions.Xj's in general are not.
I have noticeable increasesin the ass dino using champion truck plugs over the factory recommended plugs,along with msd wires.....screw after market ignition sys.

I'm with you on the aftermarket ignition systems, but do you really think you can feel the difference between spark plugs and wires? It takes a fair amount of power increase to actually be able to feel it. Sounds like the placebo effect to me. Not a big deal, if you do, you do.



multi-spark burns cleaner and more efficient because one spark doesn't always burn all the fuel in the chamber


Like someone just said, if the spark ignites the mixture, then the mixture is ignited. Unlike a diesel, a gas engine is sensitive to the air/fuel ratio, and once it explodes, it explodes. The explosion will ignite more in the cylinder than another spark will, plus with an explosion it all happens at once. Again, gas is not like diesel, diesel burns and keeps expanding as the piston goes down, but a gas engine has one ignition event so one explosion expands the gasses that push the piston down, once it's exploded, it's exploded. Don't see what a second spark would do, unless the engine is so worn out or out of tune that the first spark didn't always ignite the mixture.



The XJ coil puts out over 100,000 volts, as do all modern coils, unlike old coils that put out around 36,000 volts. You can improve on 36k volts, but it's damn hard to improve on 100+k volts. That mixture is going to ignite unless there's something else wrong.
 
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