Cascade Crew

[Xophertony]

so i am doing the research on an Multiple Spark Discharge box and have a few rounds of questions.

REV LIMITING
i am wondering if/why i should spend the extra $50 to get the 6AL instead of the 6A. other then the physical size and the carb# the two items have the exact same everything with the exception of the soft rev limiter. so $50 for a rev limiter... is it worth it?

another question: isn't it possable to set a rev limit with the ECM? and if so is there any reason i should prefer the spark cut of the MSD box over the fuel starve that the ECM will do (i assume it's fuel)? i know with the MSDs spark cut it is realy gentle on the engine, varying the cylanders to prevent fuel loading and such, is a fuel cut rough on things?

BRAND
in addition to MSD i see that jacobs electrinics, crane, mallory etc.. also make ignition boxs. i notice prety much everyone uses the MSD brand units. are they just plain better or what?

COIL
i was planning on runing it with a jocobs electronics 55K V coil per Brandon and Pauls recomendation. is this the right one?
http://store.summitracing.com/partdetail.asp?autofilter=1&part=JAC%2D380846&N=700+400360+115&autoview=sku

[izcain]

For your first question it is really a matter of opinion. I for one have the 6AL box but I have tons of add ons (in car timing controls, window switchs, ect.) I like the soft touch rev limiter cause it will randomly drop cylinders spark instead of cutting off fuel or other means of rev limiting. If it was myself I would use the one with the rev limiter since it is a safe feature for is your going to be running a car real hard and want to prevent some overreving if something was to break. I have ran with crane Hi6 and the msd and I like the msd better.

The one thing I would stress is that certain aftermarket brands are designed to work with the same company for other things. If U run a MSD box I would recommend using like product ie. MSD coil, cap things along those lines.

[Xophertony]

thanks for the input man. i agree with you on the like brand thing for the most part, but i hear bad things about MSD coils. they also don't have anny with a higher output then 48000V. in additon to having a peak output of 55000V the jacobs coil also varries the spark intensity depending on demand. that is prety sweet. but compatability is somthing to be thought about for sure. i just hear so much good things about the jacobs coils. brandon has been running his longer then most of us have owned our cars and has never had to change it. paul, and mike are running a jacobs with an MSD box.

Paul, Mike.. did you guys have any compatability issues witht the Jacobs coils and MSD boxes?

[izcain]

Well the voltage thing I can understand, but the other thing you have to look @ is not so much the voltage as much as the "real power" of the coil. Some coils have high voltage ratings but are somewhat low on the "real output". I dont see how the spark intensity would change all that much unless you were using the jacobs controller that acually made the coil hotter or colder in it's spark. I for one want the hottest spark at all times. Easier startup and faster acceleration. Been running a blaster 2 coil with my 6AL for 3 years and no problems whatsoever. I would compare more then just voltage for my basis on which coil is stronger. Just my .02

[Xophertony]

thanks izcain. i am definatly looking for that type of knowledgable input. i was also looking at peak current and spark duartion, but since i don't realy know what the numbers mean....

also do you run an oil filled or epoxy filled coil?

[izcain]

I am running a Blaster 2 coil (oil filled) and I gotta say my ignition is the hottest spark I think I have ever seen. Spark jump a good inch and a half in testing.

[chevymad]

The MSD and the jacobs coils work fine together. You won't have the full functionality of the jacobs coil using a cd box with it however. The variable magnetic core only works with inductive ignition. The amperage of the jacobs is much higher then the blaster. For awhile I took my jacobs coil out of my truck and installed it in the car. I then ran a blaster2 in the truck. I was so disappointed, I immediately ordered a 2nd ultracoil and ebayed the blaster2. It was a very noticeable difference. In the truck I run a mallory unilite, MSD6A, and the jacobs ultra coil. In the car i've run an accell distributor, pertronix distributor, or hei dizzy and a mallory VI digital, with the ultra coil. I've currently removed the mallory VI, I believe I was making too much voltage for my summit wires to handle. Car runs better with just the stock hei now and the ultra coil then it did with the mallory inline.

My recommendation on ignition boxes is the msd6aL. I think the rev limiter is a very nice function to have. I would buy another ultracoil anytime. I've had my first one since.. must be around 90. My second one I bought off ebay, no problems there either. One thing to watch though, you need very good plug wires. The current this thing puts out with a cd box is huge. You can draw a spark a good 3-4" long. I tried MSD helicore wires the first year. Totally fried them in one year. It cooked them from the inside out. So bad the wires were hard as a rock, you could hold one end and they'd be just like hanging on to a stick. I switched to belden race wire and theyve held up great. The summit wires seem to work too.

The only actual reason I even have either cd ignition box, is that at some point i've had to run an ignition that would not hook directly to the jacobs coil. The pertronix unit, and the mallory unilite will not work directly with the ultra coil. If you do not need a rev limiter, arent blown or using nitrous, you'll probably be great with the stock hei and the ultracoil. This will also allow the variable current feature to work properly.


Oh, one more thing, as much as I like Jacob's coil.. do NOT buy any of their other products. I've not heard or seen much good about their boxes. If you'd like to try the Mallory VI digital box I have, i'm planning on ebaying it. We can work out a price and i'll let you try it out first.

[izcain]

What kinds of diffrences were you having to make you disappointed with the blaster 2 coil? Just wondering if I missing out on something? lol

[chevymad]

Engine was rougher at all speeds. Kind of a vibration type feeling. Idle was slower and definately not as smooth. Exhaust smell was stronger. Everything leads to me thinking it just wasnt igniting as well as the jacobs unit. I know what you mean about the spark seeming hot, but wait till you see one of these jacobs hooked to an msd box..... It looks like lightning. If you pull the coil wire off, you get a THICK blue arc about 2" long jumping from the tower to the aluminum exterior of the coil. I think this thing would light oil. This is why its made to turn the amperage down when its not needed. The cd box deletes this feature though.

Here's some specs of the current ultra coil.


Maximum Voltage: 60,000 Volts
Primary Resistance: .3 Ohms
Secondary Resistance: 6.5K Ohms
Inductance: 3 mH
Turns Ratio: 100:1
Peak Current: 300 mA
Spark Duration: 220 uS
Weight & Size: .5lbs. 4"L x 3"W x 3"H

They're also virtually indestructable. Supposed to be watertight and withstand 99g's. Biggest problem with using one is keeping the rest of your ignition up. It will find the weak link.

Neither of my motors are on par with Twilightoptics, or Schultzy's. So you might ask them how they think it compares. I believe both went from the msd hei coil to the jacobs.

[izcain]

Well it's always worth a try I think i may just try it out... well see how well it ignites 110 octane and 11:1 compression

[chevymad]

Be glad they're cheaper. When I bought my first one it was $125.. alot of money back in 1990.

[izcain]

The coil you have is in a blue case?

[chevymad]

Yes, it's the ultracoil not one of the cheaper ones.

[Twilightoptics]

Mike and I fouled plugs more often. Got the jacobs and it smoothed the engine out and doesn't foul em anymore.

Jacobs all the way!

[Xophertony]

so brandon, (and everyone else too) you think i can get away with uing just a jacobs and not a multiple spark discharge unit? that would be fantastic for two reasons, one it's expensive, and two, iits ugly.

i like the idea of the coil turning itself down when not needed. probably saves spark plugs (and wires). i hope my 10.4MM will be able to handle it

[aaron_sK]

[Twilightoptics]

Doubt it saves anything with big wires.

MSD is a great think. Helps milage and further helps burn the fuel mixture.

What happens if you miss a shift? You zing the motor to 7k and float the valves and have all kinds of mechanical problems at that point. That extra $50 just saved your engine.

You can run the jacobs without, but it's easier to hook up with the MSD IMHO and you'll get even more out of it.

I turned down siamesed runners for an MSD and couldn't be happier.

[Xophertony]

so even though i loose the jacobs variable spark intensity you still think i should run the MSD? paul did you put the MSD and jacobs on at the same time?

oh and BTW you have sold me on the L. if i get an msd i'll spend the extra $50.

well i think i am going to get the jacobs now-ish and wait a month or two before the MSD. (but still before dyno, so i can make it part of my attempt at whooping ians ass )

EDIT* ordered the jacobs coil. this is going to be sweet. i'll wait till after christmas and see if santa brings me an MSD box

[Twilightoptics]

[Xophertony]

wait... i thought with an capacative MSD box that you lost the variable ignition intensity, since the MSD stores up the coils power and re-issues it on it's own terms so to speak.

is that not acurate?