Any Coil that performs dramatically better?
 

Is there a better, more powerful coil for MSD systems than the High Vibration coil? I see they have one model called HVC that is epoxy potted and is double the cost. Never really heard much talk about this.

Good question!
Steve

Have one of those HVCs on my car, throws a spark like an arc welder!

I'd like to know too.

theory says that you only need enough spark to overcome the potential and the conditions that exist i.e cylinder pressure, mixture etc. the dyno proves this is true. arc welder coils are, like so much of this other stuff just voodoo and shiny beads and trinkets. if your motor is conventional... i.e normally aspirated, less than 13 to one CR, and running on pump gas of some sort then the coil you buy at napa for 16 bucks is every bit as good as the best piece of garbage that MSD makes from an electrical standpoint of running your motor.

structurally is a different deal. if you have a harmonic issue such that you are vibrating the insides to bits somehow, then a solid potted transformer type will be a better solution.

I had my MSD box rebuilt and the guy that did it suggested a coil from Auto Zone. I am running that coil and did not see any problems with it on the dyno..

there is always the presumption that the consumer know what he's doing/buying , however. internal resistance of the coil is a key component in the slection process. points coils are not the same internal resistance as coils for transistor ignitions and not all transistor ignitions use the same type of coil. put a transistor "spec" coil on a points set up and the spark will be weak. put a points coil on a transistor set up and it will often burn the amplifier, especially if you leave the ignition on w/ out the motor running...

each ignition type and each transistor ignition will have its own requirement for coil internal resistance which is on the sheet of paper that was in the box when you bought it and you threw away without reading it.

Use the HVC coil and box in the race boat...great product

I've used several different brands of ignition box with the matched recommended coil, never had a problem, never noticed a difference between them. For me, it didn't make much sense to run a cheap coil with a high dollar box and expect it to work right.

I've used the Jacobs ultra coil for 12 seasons now with no problems . The H.P. fires as soon as i touch the key . :cool-smiley-011:

In the past when I was still using Mefi 3 ecms, we use to get a ton of interference from the MSD box. We would disconnect the ignition on the engine and just use a stock GM coil to do the tuning. We would then hook up the MSD box and coil on the power pulls. We did make a few pulls without the box and with the stock GM coil and there was no difference in power.
Eric, I'm pretty sure that you will not see any power difference with a different coil as long as the existing coil is sufficient....which it is.
Eddie

Thanks Steve, but I keep all the little pieces of paper that come with all the stuff I buy. I orginally had a coil that was listed on the sheet of paper.
The recommendation was from a guy that has been troubleshooting and rebuilding MSD boxes with better quality components than MSD uses, for many years. He has researched the components and the recommended coil to be a match. I used his recommendation from his years of experience. The coil I orignally used, was a source of problems in a lot of situations, according to him.

Just sharing what I have been told.

I did a ton of research into different coils and the blue HVC from MSD had the longest spark duration at the highest current and voltage. The specs on that coil were almost double anything else. When you've just spent $12k to rebuild your motor, why skimp on the coil. I will say this, the motor idles like a dream now and acceleration is amazing. My engine builder told me that a racer he builds for changed to the HVC and gained 40hp. The size and duration of the spark can effect the overall burn rate. I guess it depends on combustion chamber, piston dome, load, fuel etc.

if you actually believe... REALLY believe that a coil change made 40 more hp, then i am surprised you don't own all the swampland there is for sale in florida along with more than one major big city bridge.

in that unique case that particuar engine builder can only have had the original ignition system so comprehensively wrong that his " magic 40 hp coil " was only one single part of the fix which probably included not putting the distributor in upside down.

claims like these are just plain stupid. more voodoo and folklore.

you just need enough spark to do the job, any more than that just shortens the life of the plugs, wires, caps and rotors.

I have to admit I was skeptical of the claims, but I've known my engine builder for almost 20 years and he has never been one to exaggerate anything. It is entirely possible that this guy had a problem that the hotter spark masked. As far as the bridge goes, I'm from Michigan and the state doesn't like privately owned bridges. As to stupid, voodoo or folklore, it is possible that increasing the voltage, current and burn time of the spark generates more heat and that would impact the flame front. Remember, in the words of Smokey Yunich, "It is easier to find 100 ways to make 1 horsepower than 1 way to make 100."

Quite correct!:drink:

I am not very knowledgeable about the complex function of the ignition systems, but I thought that the MSD system fires multiple times during ignition resulting in more complete combustion of the air fuel mixture. Since the coil is responsible for creating the voltage at the time and duration signaled by the box it would seem an important part of the system. Why do you think MSD created the $140 HVC when the blasters and High vibrations are under $50. Is there a difference in the coil's ability to recover at higher rpm's? Or is it just an opportunity to turn a better profit?

Yup profit, if you'd gain anything, you will gain more from a higher dwell (longer spark) time than multiple sparks. And what you gain, probably isn't noticeable on anything we have to measure these things...

I believe you can gain 40hp on lots of combinations, all of which, were NOT right to start with. That's the problem.

If your engine is completely not running correctly, say you have WAY to much gap or something and you install a stronger coil, will the engine make gobs more power, yup. If you had just gapped the plugs correctly would you increase the power ~the same amount, yup.

MSD ignition only fires more than once a cycle at very low or idle speeds to burn overly rich mixtures on VERY high performance engines to give an acceptable idle. At mid- high speeds it only fires once as does every ignition system.
http://www.ehow.com/facts_6945909_ms...utm_source=ask

LOL I was just googling that :)

I haven't seen a magical coil make a measurable hp increase but I have seen a fancy coil KILL some hp for some reason. A few months ago I dynoed a 600 hp Pontiac 455 street engine that I built for myself thats running a mefi4 ecu and harness. We were chasing a problem on the dyno of the motor going on a rev limiter in the programming at 6375 rpms that we could NOT get to go away AND a random breakup that would occur between 5700-6200. Using taylor 10.5 mm wires, a DUI 8 pin ignition module, dui's fancy gm style 2 plug connector coil that would fit most of our gm marine ignition systems all fired by a Crane hi 6 box. The dyno operator suggested wiring in his house coil that they use on most the engines that go acrossed his dyno, a msd hi tower drag 3 racing coil. In back to back pulls motor promptly LOST 25 hp/ft lbs of tq acrossed the peaks. I also substituted a stock mercruiser 2 plug coil vs the dui and saw no measurable difference. I also ran motor on just the mefi with Crane hi 6 box bypassed, no difference in hp except before installing the dui ignition module motor would break up randomly between 5700-6200 when the dwell load would over heat the stock ignition module, it would literally be so hot your fingers would blister if you touched it. With the Crane hi 6 box we were able to turn the dwell in the mefi software down close to 1.2 ms vs the 3.0 ms that is pretty much standard in most programs at 6k/14 volts because the ignition box was giving the ignition all the dwell it needed and the module would then only be warm. It still did this with the fancy dui module BUT it shifted up about 500 rpms and again went away when dwell table was reduced while running Crane box so from my personal exerience there is some reasons to run some of these boxes when you start turing stuff near or past 6k, Smitty
On a side note, we also lost a SOLID 40 hp on the top when trying to run a K/N 3x9 air cleaner like I see on MANY bbc boats that are carbureted !!

Lots of good debate and facts on this issue. In my case I have a 12.5-1 432" Hemi, with ported and raised intake runners, rat roaster intake, single dominator no choke,big roller cam, running Sunoco 110, not so happy idling when cold (or hot),changing to the MSD helped cold idle and low speed (less than 2500 rpm) performance. Was it the coil or the multi spark at low speed? Dont know but the product worked for me. Allows engine to idle cold and pulls hard right to 7k rpm limiter.

Great minds think alike!:drink::drink:

As always, good info Smitty!

How are you liking the Crane Hi-6M's so far??? And did you use the Crane PS-92 coil in any of your tests?

What did you use in it's place if anything?

it was an easy fix. he finally remembered to take it out of the plastic wrap before he installed it.

seriously tho, smitty, why do you think that was ? that implies the thing acted more like a restrictor plate than a filter ... was it just sized way way too small for the demand ?

I have a pair of K&N's----can't remember the exact measurements, but they're about the same diameter as Smitty's and probably about 10" tall or so. I tested them on Tom Earhart's dyno with one of my 540cid N/A engines way back around 2002.

We started out with a BARE/OPEN carb---no filter or spark arrestor of any sort, then I wanted Tom to do some pulls with the tall K&N air filter on and I distinctly remember getting a 3-5hp gain---I was kind of surprised so, I had Tom do another pull just for accuracy and then took it off---still 3-5hp difference between bare/open carb and the K&N air filter!

that sort of thing is not uncommon for a lot of reasons. the whole inlet tract from carb inlet to the lip of the intake valve is all one system and changing anything always changes everything. sometimes in a big way, sometimes almost not at all. i have seen 500 different instances of exactly the phenomena that you describe for 500 different reasons. i have seen an air filter make 5 less hp and then you space it away from the carb inlet by a couple inches and it makes 10 more hp ... why ? same filter... so that tells you that it isn't the filter at all but some how some way it is changing the velocity or pressure gradations as the air get down past the throttle plate...

its a weird and complex deal that i don't claim to have any mystical insight into. all i have are the learned lesson from screwing with a million combinations in a million different ways and trying to make solid engineering and scientific sense out of the results so that the knowledge is transferable to another application.

it isn't an easy thing to get perfect and it isn't something that normal intuition generally supports...

remember the frog joke ? scientists want to see how far a frog can jump... so they put him on the ground and yell... " JUMP FROG! " and the frog jumps 4 feet. They write that down... " frog w/ 4 legs jumps 4 feet...

so they cut off one of his legs and yell JUMP FROG ! and the frog sort of scrabbles a bit and jumps 3 feet. so they write that down... " frog w/ 3 legs jumps 3 feet ...

and so on 2 feet for 2 legs, 1 foot for 1 leg and finally they cut off his last leg and they yell JUMP FROG... nothing... and they yell JUMP FROG ! still nothing...

so they write down " Frog with no legs goes deaf..."

thats what working with inlet tracts and cylinder heads and intake manifolds is like... just when you think you understand what's really happening, you draw entirely the wrong conclusion based on what you think is true...

Hey Steve, Love that story of scientific analysis of measuring frog jumping performance! LMFHO!

As with engine performance, there always is an actual reason, no matter how small or big that always answers the question of why did the outputs change. The reality is though sometimes its just not worth the trouble to find it depending on the net benefit.

An interesting fact here about the K&N filters for the Merc 496 which we have tested and saw some reduced power versus the good old stock Merc flame arrestor. The Mercury flame arrestor has a nice internal bell mouth opening into the throat versus the K&N filter that has a sharp edge opening into the throat. Air as most know likes to flow over and into bell mouth openings and at higher air flows this can make a measurable difference. Does the K&N filter filter air better than the wire mesh openings of the stock flame arrestor, YOU BET! Is its extra filtering needed in a boat, I guess that depends on the cleanliness of the boating enviroment you are in. If the extra filtering is not needed then the expense of the aftermarket filter and its resulting power loss make it not such a great buy.

It always kind of amazes me how much money, time and effort performance seeking users will spend trying to practice "Engine Alchemy" with some of the so called "magical" products that are supposed to make serious power and performance increases. If sometimes they would just spend their time and money looking at a lot of things on their boats especially hull straightness and condition, drive efficiencies in X-diemnsions, setbacks and prop setup and selections they would see and benefit from some much nicer performance increases.
I am an engine builder by profession and as such I can really appreciate products and knowledge that can and do create good added power and performance from marine engines.
I have to say though that there are small items like, which good oil I run, which good oil filter is better than another, which ignition coil I am using, what spark plug size wires I am using, and such really won't make enough improvement to be even measureable let alone translate into increases in boat performance on the water!
When a performance boater "GETS THE NEED FOR MORE SPEED!" they should try to spend their time and hard earned money on upgrades and improvements that will really translate into good measurable performance "IN THE BOAT - IN THE WATER!" , everything and everywhere else "DOES NOT MATTER!"

Best Regards,
Ray @ Raylar

This is exactly why i love O.S.O. , outstanding information !! Thank you Ray :readinghelp::circle:

Never really thought they would give or make any horsepower. I tend to use them more because of convenience, cost and appearance. But at the same time I'm not really interested in putting a restrictor plate on the motor either. Looks like some testing this spring is due.

The k/n 3" x 9" air cleaner or for that matter most automotive filters in this size are just too small for bigger cube, hi revving engines and do NOT flow enough, in back to back test, a dyno"venturi" hat , a K/N 3X 14" dia filter with flow top and a auto parts store 4 x 14 paper filter all made within 1% of each other, no measurable difference. The K/N 3X 14 with a solid lid started to kill 2% or about 8-12 hp/ft lbs of tq. The car the motor is going in is My original looking 1974 Trans Am, I want to retain the factory shaker scoop when I put my motor in, I have no problem mounting it directly to the hood but I don't want to chop up the car. A common thing guys do for these is mount the scoop to the hood and put a k/n 3X9 air cleaner on the carb and it stick into the scoop just barely clearing. I have heard that these things kill hp, not because of the design of the k/n filter media but beacuse of the overall size/square inches/effective filter area of the air cleaner itself. I wanted to see this for myself, at the time we tried it we were making 565- 568 hp pulls and tuning the efi program/working bugs out. When we bolted the K/N 3x9 (which by the way I used to run on a 455 cu inch boat motor) the hp just died, back to back pulls showed hp in the 520's . The map went from 99kpa or so at 100% throttle to about 85, the air cleaner also sucked in and afr's went pig rich. Switched back to what we had been running and hp came right back. I found some tech that claimed a K/N filter will flow about 6-7 cfm per sq inch of effective area, at 3 x9x 3.14 there is 84.78 sq inches of media, 84.78 x 7= 593cfm hence the restriction. Now, its possible that there is more effective area once you account for the pleats in the design but still the same if you have a high flowing intake sytem something this small will choke it off, Smitty

Everyone has a learning curve Ray.

I am an exterminator and I suppose I could be just as "amazed" at what you or someone else doesn't know about bugs and how to eradicate them----I could make somebody look real stupid! No matter what a person's profession....a plumber, or an electrician, or a carpenter or a computer programmer or...

It seems that what we may have learned 20, 10, 5 or even 2 years ago or less suddenly becomes kind of redundant to us because now we already know it and somehow it now "amazes" us that someone else doesn't know what we already know.

Funny thing about my own profession as a bug killer after all these years---I am still a student,---but hey, don't tell anyone! :party-smiley-004:

wow. on the gtp and gtp lights cars those motors were everything under the sun but they all made between 400 and 600 hp depending on the configuration. on the cars that i had control of, i made a large carbon airbox roughly 24 x 16 that sat over but not on the velocity stacks and used what k+n called an " air conditioner element which ws just a big rectangular deal. that was fed from a scoop over the cockpit and that seemed to work ok. when i rand the airbox on the dyno there was no dif w or w/out the filter but what i as thinking at the time was that over a 24 hr race, the filter would get dirty to some degree and i wanted extra capacity. your data is great. well done on that.

i don't think thats fair or representative of what he was saying in any way. in your business i don't figure that you have much argument with the guy that goes to ACE and gets a can of ant killer to murder a a few that are bothering him on on is front porch but you might shake your head at the guy who just had a section of his roof fall in from getting termite eaten and then posts on a forum " gee my house is getting eaten by termites. i sprayed them with RAID but they didn't die. can someone please tell me how to kill them ? "

what would your answer have been ?

That's actually not true. The Ambassador bridge is privately owned... If you want to get into the bridge owning business... Just sayin'...

:party-smiley-004:

:coolcowboy:

I'm not sure at what point air a cleaner sized like the one I saw the hp drop with starts becoming a restriction, this particular motor is 467 cu inches, has cnc'd aluminum heads that flowed 320+ cfm at .600 lift, Super victor intake thats cnc'd, Scorpion billet throttle body that is rated to flow 2000 cfm. This particular air cleaner I have owned forever, at one point I had a 455 Pontiac in a jet boat that turned 5000 rpm's with it on top that seemed to run just fine (I'm sure it made about 200 hp less than what I made with this build) and heres the best part, I raced a 69 gto that a friend owned a few times a year for about five years and we had stuck that same element on along with the velocity stack base (that I bought it with back in 1988) as the car had no hood because the intake/carb was too tall to fit under it. This car ran a best of 11.67 with the damn thing on it, we worked our way to that et from 12.20's BUT we NEVER tried a different air cleaner because it had worked on my old boat. We used to have to straighten the damn thing out bewteen passes because it would be all scrunched in. When I called my friend up from the dyno and told him about the hp drop I saw he was beside himself, coulda probably got into the 11.50's with the GTO if we would have tried something different.
This air cleaner has USCG approved stamped on the lid too, I have seen them on several boats thru the years. They also sell a 5" tall version that I have seen on quite a few race boats. The impression I get is the taller one will work with most of what we would ever run. I know this isn't a car forum and I got off track here, figured some of you would find it interesting though, Smitty

No worries Steve, I really meant no offense to Ray, you or anyone. It was late at night and I couldn't sleep---probably had too much sugar in my blood and too much time on my hands---so don't get too bent at me. I think I have been known a time or two for not always being articulate or tactful with my words. :kiss: :D

Ray has been a great contributor on the board---I was just making light of something.

I think it's a very fair to say everyone has a learning curve, but if we can help a person get passed the "curve" with some short cuts, then that's great. I believe that is what Ray does!...and I am sure even Ray had to learn it for the first time himself back whenever he learned it. :D

KAAMA: definitly no offense taken by myself with your comments. I respect everyones opinion as best I can and I definitly think we never stop learning. No one knows it all and no one ever will !
What I was trying to make a point of is that generally when boaters here on OSO post a thread with a question for the more knowledgable contributors here on OSO they do so with the hopeful idea that someone else's experience and knowledge will help them learn more and learn more quickly so that they do not always have to become the so called "guinea pig" or test bed for the part or system trials.

Let's face it its really to expensive for most in todays boating world to be guessing and learning about potential changes or additions that in many cases will be un-productive.

What I hope I can do to contribute here on OSO is help users sort thru some of the menusha and help them make good decisions about things I have good knowledge of and expierence with when they are about to spend good money and time investing in a new boat engine upgrades or builds.

You don't see me making a lot of comments here on OSO about boat hulls, drives, props, controls, etc. , beacuse I don't even consider myself to have enough expertise in thse areas to be making a lot of comments or recommendations. I try to comment and help with what I do know and what I feel may help performance boaters.

There is a underlying problem on forums and the internet and that is that generally there are a lot of "mostly intended to be helpful" replies and comments that are many times either off base or based on misinformation to begin with.

Lets hope the questions and asked for recommendations here on OSO receive the most accurate,knowledgeable and useful replies from those who can lend a hand!

Let us all post our threads and replies to show NOT SHOW HOW MUCH WE KNOW, but to help those who need the help with what we have direct knowledge of and can share with them.

This will make this forum a better place to receive and disemminate information.

Best Regards,
Ray @ Raylar