i was at the local cocoa car show tonite and the topic of ignitions cam up... i was told that with my setup i definitley needed an MSD ignition...i responded that i have heard conflicting opinions on this since my 454 isnt a high revver...i was told that the ignition doesnt "flutter" (when observing it with a light) with the MSD as it does with stock HEI...
so i asked if it would make a difference i could FEEL and they all stared at me like i made one of those stupid statemnts discussed in another thread ( see "I realized he didn't know ANYTHING about cars when he said..." in bench racing )
so whats the deal ..is a slam dunk for the MSD (6AL + coil)...i have read on a thread here that the HEI is "better than you woulda thought"

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Rich
Cocoa Beach, Fla
Team Chevelle #380
wa3men@aol.com
www.chevelles.com/showroom/70_SS_454.jpg (http://www.chevelles.com/showroom/70_SS_454.jpg)




[This message has been edited by 70 SS 454 (edited 11-20-99).]

Supposedly an HEI is only good up to 4000 rpm. I had one on my old pick-up with an Accell high output coil and never had any problems with it. A juiced up pick up and a high performance car are two different beasts. I ran a Comp 9000 in my drag car with an MSD 6AL. I have a Comp 9000 with a Mallory HYfire 4c in my Chevelle. If you want to keep your HEI, I would buy an aftermarket module, high output coil and a CD ignition box.

just this gearheads opinion

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67 Malibu 454/TH350
Team Chevelle Gold Member #97
Charleston, SC

I have an MSD HEI conversion package on my current Chevelle. This is the kit you will find advertised where you keep your HEI distributor, and use the MSD coil and control box. I have mixed feeling about this set-up. When I bought it it went on a higher-revving small block, no noticible difference on the low end, but it definitely helped the high end. I have since put a big block in the car, and since I don't rev the engine as high, I don't know that I am gaining that much. Without a rear wheel dyno, or a million drag strip passes, it's hard to analyze just how much it helps. If you get the 6AL, the rev limiter is very nice to have! The problem I have with the kit is that you still use your old probably worn HEI distributor. I have heard a few guys using distributors from Performance Distributor and liking them very much. They custom build and calibrate NEW distributors for your application. They have a web site, but I can't find the address at the moment. They also advertise in most car magazines, and I believe Super Chevy did an article on them a few monthes back with very positive reviews. A number of people on here have also talked about the pertronix set-up, but someone else will have to provide more details.

In regards to SSteve L's comment on Super Chevy saying positive comments on a product; I've NEVER seen a negative thing said in any of the car magazines!!

I personally am using the MSD Pro-billet distributor, but see nothing wrong with the factory HEI if set up correctly and you are not running at a real high RPM.

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Wes. Vann
Technical Reference section
Gold Member #5

I would atleast upgrade the stock HEI coil to a higher output. Davis Ignition makes a setup that works really well.

I took my HEI, tore the coil and module out, and installed a holley annihilator behind it. I like the pole seperation of the HEI and the mag trigger in it, and I now have the better spark of the CD system. I'd upgrade. It is popular for a reason- it works, and darn well.

I doubt if you went out today and bought a MSD system you'd notice a little, but nothing to make you yell out in joy. The guys you were talking to sound like their in that "if its mainstream, its good" mold- and if someone mentions they still use points then their the antichrist and should be stoned.

Gee man, don't you realize anyone with an MSD setup is obviously better than you. You need to go get one, and NOS, and a supercharger before you'll be cool.

Wes

Rich, IMHO a stock ignition is a high state of tune is perfectly capable of firing any normally aspirtated non squeezed mill. I think that any performacne gains "felt" by adding an MSD is caused by the box covering up any operating inefficiencies in the current ignition system, i.e., it;s not in good tune.

I had a "valve float" problem in the first hot mill I built as a kid, a 366ci LT1 clone. Float at 5500. With an MSD 6. Changed the module( stock 1975 )and found the real float at 7200. Whoops.

The benefit of an HEI, Pertronix, or Unilite, is the very accurate spark timing as compared to points type distribs.

Dale of the Mag Shop here in Buffalo taught me something about hi voltage coils. Think of coil current output as a constant and voltage and amperage as variable V(A)= C.
If volateage is high, ampereage is low and vice versa. So a high voltage coil, may actually begin to foul plugs if the motor is run at a low, or normal cruise rpm for an extended time. A stock coil may be best for this (30,000-37,000 volts). At high rpms, the higher electric potential, of the high voltage coil is better at firing the mixture. So a 60,000 volt coil on a grandma car will eat the plugs and probably foul them out. While a 30,000 stock coil won't fore the mixture at 9,000 rpm. It's a compromise given the average opreating rpm of the engine.

He told me I should consider an MSD not for performacne gains, but if I was fouling plugs alot, or if the plugs were hard to change. The use of an MSD will extend the life of your plugs.

Thankfully, one good attribute of the 2" Hooker Comps on the 427 is very easy plug removal.

I run a custom curved new small base distrib, with Pertronix and a stock replacement coil. It fires a relatively "dirty" burning, mid compression ( 10.8:1), 427 to beyond where the cam runs out (6800 rpm). I would bet my last dollar that adding an MSD would not cause any "felt" improvement in my "rip ability".

If I ever add squeeze, it's probably useful to add a CD box.

Also, I run solid core wires. Why? It gives me Better AM reception! I've always been hard on my wires and these are relatively bulletproof. And finally, I don;t care what you guys say, my wires give me 1.5 ohms resistance end to end. Even the best resistor wires show 3000-4000 ohms. Sorry Charlie, I may have more spark than you MSD boys with my measly 37,000 volt coil.

Anyway, stock works well with the L88. I'd spend the money on curving. Rent a sun machine and expert for an hour. That'll help you more than an MSD. Unless something is subpar in your system now.

There's my very long winded dissertation on what I know of hi po ignitions. Probably could've been much much shorter.

Gene Chaas
Gold Member 62
67 SS396/ 427

[This message has been edited by Gene Chas (edited 11-21-99).]

A stock HEI with a proper 12 volt feed is an excellent street setup. In good condition they don't die at 4,000 rpm. The 4,000 fairy tale must have been made up by an aftermarket manufacturer to boost sales. There isn't even anything wrong with a good heavy duty points setup either. There was a magazine article a while back comparing Hei, points and an aftermarket electronic setup. The engine with the points was putting out the most hp at 7,000rpm. Points will last 10,000 miles and how many years will it take you to put that on. Dwell adjustment is a 2 minute job at most. Best of all you can go into any automotive parts store and get any parts you need for these old standbys.
12.5 -1 compression, blowers, and nitros may need something better.

Here is the bottom line. If your current ignition system, be it points or msd or hei or? is capable of delivering a spark, which ignites the fuel mixture, nothing will be gained by switching to a higher output unit.

That means if your HEI is not having a problem igniting the mixture right now, you will not notice any difference with an MSD.

However, there are different circumstances in which your HEI does have trouble igniting the spark, and the MSD will absolutely cure those.

I have noticed, that generally, with an MSD the engine starts with less cranking time, tends to idle a little smoother, and can be run a bit leaner at cruise before a missfire is encountered.

HTH

I tend to agree with the last few posts.. first of all if your HEI wont keep up at 4K rpm then its junk, get a new one. I have run 6500 w/ HEI and it doesnt give a hint of incompetency...

I think 68blown has a good point.. if there is a spark that ignites the air/fuel mixture, then thats that. whether its a aim&flame spark, or a blowtorch, its going to ignite.. The benefits of the expensive stuff comes at super high rpm stability, etc....

thats my two cents.



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Mike Reeh
Gold #34
San Diego, CA

I know very little about electricity but, I heard the biggest advantange of the "MSD" is they deliver the spark more consistantly at higher rpm levels. Also, the rpm limitations on an HEI has been quoted to be between 4000 to 5000 rpm? How 'bout somebody hold onto the wire & tell me which is better 4k or 5k rpm? http://www.chevelles.com/forum/smile.gif http://www.chevelles.com/forum/biggrin.gif http://www.chevelles.com/forum/smile.gif
Most street driven cars rarely go over 5000 rpm anyway
IMHO

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Lowered '67 Elcamino
ZZ430 eng / 4L60E trans
"Canyon Carver"

I went from a stock HEI to an MSD 6AL, and only noticed the difference at idle and low RPM. The MSD box keeps the plugs much cleaner putting around town, but it did not give me any more high RPM potential. I shifted at 7800 before AND after.

well im with you guys...this distributor was recurved before i got the car to ru on regular fuel i was told...when i first started driving the car, before i knew what to expect and how to handle it, i goosed it and she went rite up to 7000 in a flash, in fact before i knew it...now my tach may be off by a couple hundred rpm so at the very least she ran rite up to 6500...never noticed any problem other than that i freaked cuz i had "overrevved" it without reallizing she would run up that fast...

so i think ill save my cash for some real improvements..

as usual, thanks guys



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Rich
Cocoa Beach, Fla
Team Chevelle #380
wa3men@aol.com
www.chevelles.com/showroom/70_SS_454.jpg (http://www.chevelles.com/showroom/70_SS_454.jpg)

Sorry guys, Wes V is right, I never saw a magazine say much bad about their sponsors products! What the heck was I thinking? I guess after re-reading my post, I realize I didn't say what I meant. I am not sold on an MSD fired ignition in a "lower" RPM street app. I guess I was refering to the Performance Distributor set-up (made by the fore-mentioned Davis Ignition) because they set the curve for you based on your application. I can't find a shop around that will do much of anything with recurving a distributor, even in an off highway race only application. The guys that said they could do it couldn't properly explain what was involved, so I thought I'd look elsewhere. My goal for this off season is to read up on how to recurve my own distributor. I have noticed a few detailed posts here before, and will search them out. Sounds like a real low cost way to wake up an engine.

One thing that was not mentioned is the multiple spark capablities of the MSD, not just one spark but muliple sparks for 20 degrees of crank rotation.I use the 6AL with the HEI dist and the MSD blaster 2 coil the spark from the coil is somethng else you could weld with it.Well all most nothing for it to jump 4"...FRED

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An HEI is all the ignition all stock and most performance engines need for proper operation. There is one very good modification over the usual curving and rebuilding that is generally needed for a wrecking yard or running-in-car HEI, move the coil out of the cap.

There is no coil that is mounted in the stock cap that is better than a remote coil for an HEI. The design of the incap coil won't let it be improved much, period. When the coil is removed from the cap, inside cap temps go down between 30 and 40 degrees F. and the overall operation of the distributor gets better. Kits are easily obtained to do this from most ignition sources and it isn't hard to make the coil cap mod to do this.

In general, if you need an MSD for a stock or moderately hopped up engine (normally aspirated, not nitrous, blown or turbo'd), then you had better find out what is wrong with the engine or tuneup on it. Multiple spark operation is a moot point if the engine is properly built and tuned right, it then only needs one pulse per cylinder per spark event.

For racing, blown or nitrous operation and seriously high compression street and racing engines, then the MSD simply cannot be beat.

Jacobs is a joke, Mallory is now owned by Mr. Gasket, like Accel is, and is now seriously overpriced and outdated, and Holley isn't even in the picture on anything street driven.

Any ignition isn't a cure all for a poorly running ot mis-tuned engine. Certainly, the HEI can have problems like everything else, especially when people get the idea they don't need maintenance, but they will do a great job over most performance ignitions on most street driven vehicles for many, many miles and still be cost effective instead of cost prohibitive.

Amen IgnitionMan and Fred. Ever wonder why you can't use a dail type timing light with a MSD ignition????....Multiple spark. HEI is great but MSD is awesome.

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Mike Hurta
(Aug98)
Gold#25
Clute, Texas
www.chevelles.com/feature/aug98.html (http://www.chevelles.com/feature/aug98.html)

Wait, wait, I gotta go back to Cardiac's comments, " Most street cars don't go over 5000 rpms." You gotta be kidding. You mean street cars like grndma's Caprice, or street cars like our street cars. The fun just starts happening at 5!!!!

IgnitionMan...which coil do you recommend and what do i need bessides the coil to get it installed... which wires and looms do you recommend as well??

is there s diffeence in looms from a a performance perspective?? plastic rather than metal i suppose??

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Rich
Cocoa Beach, Fla
Team Chevelle #380
wa3men@aol.com
www.chevelles.com/showroom/70_SS_454.jpg (http://www.chevelles.com/showroom/70_SS_454.jpg)

70SS454, depending on just which distributor you want to use, there are a number of ways to go.

If the distributor is a large coil-in-cap HEI, and you wish to run it as the HEI, I suggest using MSD 8401 modified dust cap, 8202 ignition coil, and fabricate the coil wire from a spiral core wire from any good auto parts store. This setup will give a stock HEI, with remote MSD blaster II coil.

Same large cap HEI, for use with MSD ignition box and coil, and to remove the stock HEI module, use MSD 8400, uses 6A box, remote coil (no rev limiter), or the 8500, uses 6AL box, remote coil (with rev limiter in-box). Either of htese units is a great changeover to use.

If you wish to run the point distributor, I DO NOT advise using the Pertronix Ignitor or Unilite conversions, as the only benefit is the removal of points, not plug voltage increase.

If you are interested in a dedicated HEI (not junk), or an MSD pickup trigger installed into your point distributor, please contact me at the e/mail address listed, and I can direct you to same.

ALWAYS, ALWAYS use a spiral core wire for the plugs, they are fully compatible with either an HEI or MSD setup. The best cost affective spiral core wire sets are the Borg-Warner SELECT wire sets, marketed by, of all stores< Pep Boys and others. Full lifetine warrantees and affordable cost for the wire sets, and they are the same as sets costing much more.

DO NOT let anyone talk you into an older set of wires, either non-spiral core or solid wire, the new ignition systems won't tolerate the cross firing and overworking of the systems these wires allow.

Always use plastic wire guides, the metal ones can contribute to spark voltage loss in the wire run to the plugs.

Hope this isn't too confusing.

I use an msd distributer, 6AL, and used a msd coil. I'm not impressed by the system. 45 KV is pathetic, and the amount of dwell the msd has is pathetic. Not to mention the pick up coil and reluctor constantly rust and seize up my advance weights. My 6AL box also loves to fry ignition coils. The multiple spark function is over at 3000 rpm. New cars with DIS have about 80 KV and 10 times the spark duration of single coil systems. If I were to pick an ignition system today I would buy an electromotive DIS.

Steve, your experiences with the MSD components are unique. I could see the problems being more widespread in MSD users if the wrong type wires are used (solid copper or steel core), or crossfiring when the wires aren't routed correctly, but not when the spiral core wires recommended and correct routing is used, and maintenance is done correctly and on time.

MSD systems do stop making multiple sparks after 3000 rpms or so, when the engine doesn't need the multifire assist for things like higher compressions or long duration cams, and this is OK, if the ignition curve(s), carb/jetting and engine configuration are all compatible with each other.

The DIS systems are nice, but overpriced and just not nescessary for the average mild to moderately modified street/mild strip engines we all use. The Electromotive system would have to be Capacitor Discharge to make the voltage you say it does, and I have not seen over 49,000 volts in any system, and certainly not the stock DIS offerings. Maybe the Electromotive system has the capability to make the voltage you say it does, but for the average person, the system is far overpriced compared to either the HEI or MSD systems that work just fine when applied as the instructions recommend, and use of quality parts instead of junk off-shore parts.

I see lots of MSD distributors for things like recurving and routine maintenance, and never have seen the rusting you allude to. I also build HEI systems and trigger pickup setups into small point distributors as my full time business, using MSD and NAPA (Ford type) pickups and reluctors (same manufacture pickups and reluctors), without rust and problems. With proper maintenance to the mechanical advance in any distributor, lubrication and cleaning, I have not seen any rusting problems, just sticking from neglect and dirtiness.

Ah Ignitionman, then you must agree that a small base w/ Ignitor and a stock coil is all you need to fire a fairly high revving stock L88 427?

Gene, NOT A CHANCE FOR THE IGNITOR!

I do not install, use or service Pertronix Ignitor, Mallory Unilite and Compu-Fire units in anything. In my extensive testing, the units I just listed do not increase firing voltage to the plugs, and just eliminate the problem of having to deal with points, admirable, but no other benefits. The Pertronix system functions best with a dead stock coil, and the output will not exceed the voltage the plugs need to fire, same as points, about 6,000 to 7,000, no more. These systems are NOT HIGH ENERGY systems.

I had the chance to tailor my business around any type and manufacture ignition system I wanted when I first started it, and I chose to install a dedicated HEI system into the stock point distributors for most American made engines. My criteria was, and is, to offer either a dedicated HEI or trigger pickup for use with MSD, built into the stock point distributor for ease of parts acquisition, appearance, and clearance. This allows me to get a better quality performance coil, mounted outside the cap, so the typical 40 to 50 degree temperature build-up seen in coil-in-cap HEIs, ISN'T in my units.

Since I use an MSD pickup and reluctor, and a GM 990 series HEI module, I get a much better pickup than the stock HEI pickup, and a good 7,000 rpm module, with the remote coil, no ballast wire or resistor, and with a good set of spiral core wires, .050 plug gaps and a true 32,000 volt output to the plugs (more than adequate for the properly set-up and tuned engine).

The weakest link in the stock HEI is the high tension coil, and it needs to be of better quality and the most important fact is it needs to be moved out of the cap. There is no good in-cap coil that works better or near the round aftermarket coils by either MSD, Accel, or Mallory. Jacobs coils are stock GM performance coils, re-labeled, not worth the effort, and the Pertronix coils are same as Jacobs.

All this with readily available at any good auto parts store parts, good reliability, and more spark output than a stock HEI.

For the trigger pickup only distributors, appearance, and the ability to use the MSD ignition boxes and make the whole system look stock with a hidden box mounting. Plus, the cost for a trigger distributor is cut in half over the MSD distributor, and still uses the same mechanical advance adjustment methods.

Pertronix Ignitor, not a chance, thanks.

Yes, DIS systems are gtreat, if you have the bank to afford them, but aren't really practical because of their price, for the average daily driver vehicle.

Sorry if any of you dis-agree with my years of testing and experience, but that is just what has been proven to me, time and time again.

This is NOT meant to be a plug for my business, just the point of view from someone who works in the ignition business. Please don't make anything more of it than it is, my opinion. Thanks.

[This message has been edited by IgnitionMan (edited 11-26-99).]

Well I just had the pleasure of changing the control module in my 69 Chevy truck (has 74 Impala 350) with H.E.I. IN THE RAIN! And I have a cold. What a thing to have to do on my birthday.

I prefer good old points. At least they don't up an leave you stranded at any moment.

Hey everybody, better keep an extra module and the tools to replace it in you vehicle. I've never heard of one going while your driving. They seem to go after you shut the engine off. At least I was at home and had a spare.

Now, could I have a few good reasons for not changing this over to points? Maybe im too old fashioned.



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Bob (Pa.)

1963 Impala 283
1966 Chevelle SS 409
1969 Malibu 307
1972 Malibu 307
1969 Chevy stepside 350

Bob's 409 Chevy Page

silverstone.fortunecity.com/tvr/246/bob_s_409_chevy_page_index.html (http://silverstone.fortunecity.com/tvr/246/bob_s_409_chevy_page_index.html)

Bob, you might check for the coil just starting to get a layer short, or a voltage surge from the regulator. These two things are the biggest causes of HEI module failure.

Usually, when the coil is starting to go, the module runs hot from the layer shorting making the module work harder, to make up for the added resistance the coil has.

If it coughs another module, then look for the coil or the carbon center post doing the damage.

I have seen even the later model internal regulated alternators have internal grounding problems, and this too, can cause HEI modules to fail when a voltage surge happens in the circuits. I have seen voltage surges in the 50 volt range, and they just make Unilites go instantly blind.

HEI modules are usually reliable, until something else causes them to go out, and those problem causes should be looked into and fixed.

My '82 S10 stuck it's 78 amp regulator one day a while back, and the only reason I noticed it was from the melting smell from the computer. I was lucky, I dis-connected the alternator wires and continued on my way, fixed the regulator the next day, no biggie. My voltmeter read 18 volts when the regulator was still plugged in. Like I said, lucky.

Still, I believe in the HEI, millions of them still going very, very strong.

IgnitionMan...
its great to have a technical expert helping us ...but man, you lost me...
so lets do this again...

when do you recommend an upgrade form stock GM coil in large cap HEI??
is it good enough for most daily drivers??
how can i tell if its not accepatable (i assume this means igition breaking down at hi RPMs) but what do i look for..
as far as i know, this ignition HAS done the job just fine and i have been up to 6500...

in simple terms, and in order, what would you recommed one do to a stock GM HEI (including preferred brand names and part numbers) to provide a good (not overkill) ignition system for a daily driver that occasionally sees 6000

454 9:1 CR TH400
coil in large cap Stock GM HEI

sorry to be dense but i really want to absorb your knowledge!!

thanks for your patience!

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Rich
Cocoa Beach, Fla
Team Chevelle #380
wa3men@aol.com
www.chevelles.com/showroom/70_SS_454.jpg (http://www.chevelles.com/showroom/70_SS_454.jpg)




[This message has been edited by 70 SS 454 (edited 11-26-99).]

I'm with Rich. I'm very glad to see IgnitionMan show up when he did! One of my goals this "off-season" is to learn more about ignition systems, and what I should do with mine. Ignition Man, you refered to your HEI dedicated system in a small cap points distributor. Is there any big difference between this set-up and an HEI large cap distributor with an external coil conversion? Is it easier to limit or cut back the mechanical advance on a factory points type distributor than on the HEI version??? This is the first area I think I need to address to get some more power out of my engine, recurve the distributor, more initial advance and less mechanical. I currently have an HEI distributor out of a 76 chevy truck, and removed the coil and module by using a MSD conversion kit with a Blaster II coil and 6AL box. Would I be better off in any way beside physical clearance around the distributor with the points type unit with the conversion you speak of??? I was considering an MSD distributor, but the small GM model would be sweet because I have my 6AL box mounted under my dash, and with the small distributor it would certainly be more stealth yet. It seems that this is the biggest reason guys like the Pertronix system, stock look. Any and all comments appreciated!

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Steve

72 Chevelle SS402/4sp

Ignitionman, I use spiral core 8.8 accel wires with autolite 25s, and my wires are well separated with a moroso kit with special attention to 5 and 7. My car is a daily driver and there is nothing I can do to prevent corrosion of my distributor except keep it lubed with WD-40, which helps, but is a pain because the relutor is made of soft iron it is all but impossible to stop corrosion. All my wires are a 1/2 inch from each other and a 1/2 inch from any metal. The electromotive DIS system sells for 500 or so bux last time I checked. Newer ignition systems crank out 80 KV +. "Do not, under any circumstances, open circuit one of these plug wires. some of the systems are capable of producing close to 100,000 volts!" That quote is from Automotive Electricity and Electronics writen by Al Santini. I've seen waste spark systems crank out 80 KV on ignition scopes (fluke 98) myself.
I'm not impressed with MSD systems, but it does get the job done. I wouldn't say any better than HEI systems.

I have never seen a MSD reluctor that has rusted, all of the ones I have seen are iridited to stop corrosion (the yellow patina they have). The average everyday driver engine and most strip engines don't need near the voltage you say these systems produce.

I have worked with wasted spark systems for years on motorcycles, as well as dedicated systems on automobiles, and I can understand the need for a system that makes those voltages for sparking two plugs at the same time, but the total voltage at each plug is not 80,000 volts, but half that, for each plug. That makes each plug get 40,000 volts each, well within the levels the average MSD system makes per impulse cycle. I have watched the outputs for these systems on many a run, and the output patterns on a few different scopes, without exception, they make half the advertized output at each plug, and one plug fires from the positive to negative electrodes, the other one in the loop fires just opposite, negative to positive.

One of the best wasted spark systems for a 4 cylinder was the Yamaha Seca and Maxim 550 cc ignition, battery CDI, wasted spark type, worked well. Other motorcycle systems were transistor controlled, breakerless inductive, and didn't make nearly the voltage the CDI system made, still, no misses or breakdowns, no multi-fire either.