It will provide multiple sparks (one at the set timing with one just before and just after) to give you a more complete burn. It only does this below 3000 RPM, if I recall correctly. It will do absolutely nothing for you with a stock engine. It is designed for high compression racing engines that cram a lot more fuel in the combustion chamber. You will probably notice a smoother idle, but that's about it. They are intended for racing where a stable spark is needed at high RPM and gives you the ability to add on rev limiters, delay boxes, RPM activated devices, etc. Not much use on the street.
At least that's been my experience in 30 years of hot rodding. I had a 6-AL on a tunnel rammed 350 that would spin 6000 RPM. All I noticed (besides the handy rev limiter) was that I had to buy an adapter to make the tach work right and every time I spun it up that fast I got pulled over. All of those problems went away when I sold it
------------------ 1986 SE Aero coupe.
3.4 DOHC swap is complete and running, now just have to finish the rest of the car...
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12:29 PM
AL87 Member
Posts: 2578 From: Bradenton, Florida, United States Registered: Mar 2010
Im not too concerned about the plugs since they are just regular copper core. the wires are just standard autolites, so that may be bad. (time to go get some 10mm race wire.)
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02:47 AM
jetman Member
Posts: 7804 From: Sterling Heights Mich Registered: Dec 2002
I have not experienced any difficulties with AC Delco spark plugs or either MSD or Taylor wires, they're always fine, been 8 years at least so far.
The MSD coil will definitely torture the rotor and cap with that hot spark.
The MSD 6A definitely smoothed out the idle, I get up to 1 MPG better mileage, stock engine, nothing else special except a little bit of wow factor whenever I open the rear deck lid. Not the best picture but nevertheless.
------------------ jetman Silver 86 SE 2M6 4-speed, with "check wallet light" Now fortified with 8 essential slices of bacon goodness
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06:17 AM
rcp builders Member
Posts: 736 From: north port, Fl. Registered: Apr 2007
as above: MSD = Multiple Spark Discharge it does this with capactive discharge, which is very very fast - which allows up to 3 sparks to happen. as RPMs go up, the number of sparks drops - but they are still very powerful sparks.
while that sounds great - this super power spark puts a helluva load on the rest of the ignition system. burns thru caps, rotors, wires.
now, if you have a boosted, nitrous or high compression - you do need a more powerful spark to spark thru the denser fuel/air mix. there are good reasons for the Ignition Boxes. and, it will also mask some the weaknesses of the stock coil at the higher RPMs (which a stock Fiero also cant reach due to the intake...), because the stock coil starts to fail at about 4000 RPMs. But - the better solution is just to get the MSD coil, and skip the ignition box. much cheaper. MUCH more reliable.
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12:05 PM
AL87 Member
Posts: 2578 From: Bradenton, Florida, United States Registered: Mar 2010
as above: MSD = Multiple Spark Discharge it does this with capactive discharge, which is very very fast - which allows up to 3 sparks to happen. as RPMs go up, the number of sparks drops - but they are still very powerful sparks.
while that sounds great - this super power spark puts a helluva load on the rest of the ignition system. burns thru caps, rotors, wires.
now, if you have a boosted, nitrous or high compression - you do need a more powerful spark to spark thru the denser fuel/air mix. there are good reasons for the Ignition Boxes. and, it will also mask some the weaknesses of the stock coil at the higher RPMs (which a stock Fiero also cant reach due to the intake...), because the stock coil starts to fail at about 4000 RPMs. But - the better solution is just to get the MSD coil, and skip the ignition box. much cheaper. MUCH more reliable.
Hey Pyrth,
What do you consider to be high compression? Are you thinking something like 10.25:1, or would my 9.2:1 be considered "high" compression (at least with respect to a Fiero motor)? I have a 2.8 that I rebuilt some years back and used a 3.1 crank and rods with some .040 overbore pistons (higher compression ones) which supposedly brought my compression up to 9.2 something to 1. This is what the machine shop told me years ago. I drove the car around for a bit, and then stored it for like half a decade. Just wondering. I was thinking that I'd like to install one, but I'd want to try to hide it somewhere so I could keep the engine bay relatively stock. I already have the Accel SuperCoil (which I painted black).
quote
Originally posted by jaskispyder:
Stock 2.8l? are you planning on a new engine soon?
Yeah, I used to do that all the time too...
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06:13 PM
PFF
System Bot
Dennis LaGrua Member
Posts: 15943 From: Hillsborough, NJ U.S.A. Registered: May 2000
Just a word to the wise. MSD boxes are intended to be mounted in a place where cool air will circulate over them but there is no cool place in the Fiero engine compartment. They will last for a while by mounting them in the trunk but hot summer days can shorten their life. The good news is that MSD offers a very good repair service and the costs are reasonable.
------------------ " THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Powerlog manifold, Northstar TB, LS1 MAF, 3" Flotech Afterburner Exhaust, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, HP Tuners VCM Suite. "THE COLUSSUS" 87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H " ON THE LOOSE WITHOUT THE JUICE "
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06:46 PM
E.Furgal Member
Posts: 11708 From: LAND OF CONFUSION Registered: Mar 2012
for one a efi stock engine doesn't need one.. they are for high strung engines that will load up plugs at idle and/or have high dynamic compression that could blow out the spark or cause it to not fire in the first place.. they where big in the 80's-90's on street cars because stockers where tuned so lean.. that missfires was a common issue even with tip top parts.. less chance of missfire when you get 3 sparks back to back.. it doesn't shorten the life of wires or plugs and it does shorten the caps and rotors.. and weak coil will show it's face clearly with one of these.. as they can't renergize fast enough.. and you get a mid to high rpm studder.. that tends to break things..
Multiple spark is not just a feature. What MSD doesn't tell you that system needs to run multiple spark to just run the engine.
Why?
Many think that any spark will ignite flame. This is wrong... Engine Need a spark that last long (Actual spark Dwell time) to transfer spark power to fuel mix. Too long just waste power but too short then no fire...
Capacitance system makes a spark that is too short to reliably ignite fuel mix at idle to whatever RPM. Their fix is to use multiple spark to = 1+ sparks that normal system makes.
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Running MSD etc "performance" coil can/will eats dist cap and rotor. For one, They hate carbon brushes that most caps have. Some make a copper button to replace carbon.
------------------ Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should. (Jurassic Park)
