Ignition coil...which one?
 

I am looking to buy 2 new coils, mostly as the stock merc coils I have now are ugly but also to have new parts as well as any possible added performance/reliability.

Anyway, I was just wondering what you guys are runnning and what you would say the best one is. MSD blaster, high vibration, accel????

i think the msd high vibration coil is a good choice,they are fairly cheep,and seem to hold up well in the rough marine application,i also like the msd blaster ss coil.

call me old fashioned but if what you have works fine then clean them up and paint them or worst case, replace like with like. i have never seen ANY aftermarket coil perform better than the stock hei stuff in what are essentially stock applications. its the zoom factor marketing... spend your money on important stuff like women and alcohol and leave the aftermarket junk on the shelf

Ive been running the MSD Epoxy Filled High Vibration coils for years. No issues and they're affordable.

so are you saying that the parts that come stock are the best,and all the aftermarket parts are junk?

in broad strokes, yes. in the vast majority of cases , and i would put that number at 95 % , on engine combinations that have been done by real oem manufacturers and barring some bizzare and crazy modifications that then require some alternative system,
yes. the factory stuff is best every single time. i have run hundreds of different combinations from esentially every manufacturer on earth at one time or another and in every case have yet to see an example where some aftermarket part was BETTER than stock... and by better i mean either a quantifiable increase in power or torque on the dyno or in the cases where the dyno wasn't available and we did back to back race track testing, i never saw a single instance where the lap times were better.

i include mercruiser in that list of oems. there isn't a thing wrong with that gm system nor will bolting on any msd junk.. and their stuff IS junk, make any difference at all in performance.


an addendum and an example... i ran a catagory of sports racers that required a 2 litre for motor. those came with point distributors. so everyone went to aftermarket relucter systems of some sorts and MSD 6 's. i ran a distributer pack and coil from a nissan b210... an econmy 4 cylinder nissan. aside from wing any number of championships, i never had an ignition failure of any type ever. the msd guys all carried 2 spares in the trailer and a spare prewired into the car...

why do you want ignition components where you have to have a spare on your key ring just to get home ?


now... just so that i am not misunderstood... i am NOT saying that all stock ignitions are best for all combinations. clearly that is not the case... a AA fuel dragster making 5000 hp at christ knows how much boost and 15 gals of fuel in a 1/4 mile needs a different system than your motor...

but what your motor, barring supercharging, or some other extreme set of modifications will work better with a properly operating stock system than anything the aftermarkert has to sell you.

actually one correction about oem stuff... the british stuff was and remains complete garbage no matter who made it. even msd stuff is better but then again having a ligtning rod taped to your roof was more reliable than both of them

fixx
 

i had the best luck with mallory, the black plastic promaster oil filled race coil..25 + yrs and counting..

here is the newer marine version..
http://www.jegs.com/i/Mallory/650/29...oductId=748657

i cannot agree with you,for example,the best cylinder head from gm is junk compared to a dart machine head,and all other aftermarket head made in the usa.and you cannot compare a gm crankshaft with a callies magnum crank,it,s not even in the same league.i could go on and on,i dont know anything about aftermarket parts from your part of the world,but here in the good old usa,the best aftermarket parts are made and sold.

well... with thought process like that, it is not hard to understand why you don't agree.

we are not talking about fundemental structure or components. he didn't ask " gee if i take my oem 502 and replace it with an aftermart illmor, will i have more power ? "

we are talking about ignition coils. and in deference to you i will use small words and short sentences while i explain my position...

in my experience the aftermarket ignition industry rarely , if ever, has produced anything better than stock oem components.

i am not talking about cylinder heads , crankshafts , or any other component manufactured in any way by anyone else.

if your limited intelligence keeps you from grasping that concept , get your 6 year old to explain it to you.

and yes... in case you are wondering , i'll make it clearer...

i think you are stupid.

I've been told you can't run an aftermarket coil with a TB IV because the resistance will kill the box,, any thoughts on that???

You need to make sure the coil you select is designed for the type of ignition you have. There are different coils for points style, CD, and Induction and even at that there are different coil requirements even within the same manufacturers CD line. Coils are designed to work with different primary voltages, current and dwell. Make sure you know the specifications of the system driving the coil before you select one.

I've been using the Crane Hi-6M box and Crane PS-91 coil with thunderbolt distributor on my engine and never and issue. Now I agree with Steve there is nothing wrong with stock ingnition stuff. I needed to change my advance curve and it was cheaper to by two used crane boxes than it was to locate two V-6 modules. Now that said the V-6 module would have made an easier and cleaner install and most likely would have worked just as well.

In October/November I spent 2 weeks dynoing a 467 ci Pontiac that made 588 hp ( similar numbers to our N/A boats). I used a MEFI 4 ecm and ramjet 502 efi harness, I also converted a older hei to a newer style GM 8 pin "2 plug coil connector" module ( the same one most bbc boats used from 1994 to 2002) so the system would be plug and play. The coils that plug into my wiring are the same coils that my mpi boat uses, the gm 2 plug connector style. I had a DUI high saturation/higher voltage coil, Msd's "better" coil and the original one that came on my boat new in 2000 that I keep on the boat as a spare for the Msd I run. In back to back testing there was ZERO measurable difference between any of them, this was a 11.5-1 motor that turned as high as 6700 (hp peak was at 6200). There also was ZERO hp difference between the stock ecu firing the ignition and using a Crane hi 6 box except a cheap replacement stock ignition module in the distributor would overheat after1-2 pulls and make ignition break up around 5800 and after switching to a DUI ignition module this would happen around 6200 or so and because I was running a Crane hi 6 box I was able to turn the dwell setting/tables DOWN in the efi programming (which took some load off the ign module in the distributor) and rev motor as high as I wanted to without ign module overheating. That was the ONLY benefit I found from the ignition box, and again saw ZERO difference from the coil. I was really surprised, though I would see something somewhere.
Now on my boat, a 8.2-1 540 with a blower running as much as 14lbs of boost the Crane box and previous Msd box seemed to clean up the soggy idle but never saw any difference between after market coils and the stock one, fwiw, Smitty

I don't think anyone here is suggesting by adding a aftermarket coil that there is power to be gained.

I think the standard Mercruiser Thunderbolt IV is a good system, and works just fine for almost all stock applications.

As far as a replacement coil, we aren't talking about a major modification here. Its a coil. I will bet you, that very few of these coils, whether it be mercury, petronix, msd, standard motor products, sierra, omc, accel, mallory, etc, are being manufactured in house. At least when it comes to these standard round style oil filled coils.

There is no way these companies all have little "coil departments" with a team manufacturing the cases, windings, terminals, etc. Funny how a chrome coil cover or a coil bracket from jegs will fit 90% of these coils.

I look at it this way. Coils can go bad. Car, boat, etc. I choose to run a "MSD" coil, mainly because if one take's a crap on me while in the middle of a boating trip, I can go to any auto parts store, most of the time in walking distance, and get a replacement. I wont have to worry about it being sunday and the merc dealer is closed. Or, I can't tell you how many times I've made a trip to the local mercruiser dealer, to do nothing but waste my time, because they rarely have what I need in STOCK. I always get the "we can have it in a day or two" from the parts guy. Well, so can I if I order it online, and I don't have to go make a second trip to get the part, and chances are it will be cheaper anyhow online!

Just as much as I get tired of reading about the aftermarket "snake oil", I am equally as tired of reading about the "buy genuine merc stuff, its the best " snake oil advice too. Over the years, just about every single part on a mercruiser engine is outsourced. The engines are Stock GM, the water pumps, carburetors, intake manifolds, fuel pumps, alternators, starters, bearings, seals, and so on.
If you like taking it in the A$$ repeatedly, stick with merc part numbers and prices. They will surely be glad to provide with a 200% markup on the products they provide you with.

Oh, and stevesxm, in case you were wondering, I think your an @sshole. :asskiss:

As always, good info Smitty!

Smitty always has some useful information!! He's always got something interesting to talk about!

smitty you are spot on....same here, no diff in boxes etc as far as H/P....now with coils have to be careful as mentioned as some don't work with other componants and some designed for short runs(drag racing) and will over heat on longer run times...

We tried a MSD drag coil on dyno and lost a ton of hp (35 if I remember right) BUT not sure it was compatible with box/ecu, Smitty

As far as Stevesxm, I completely agree I wouldn't change a oem coil just to spend money BUT I wouldn't pay Merc a stupid amount for a replacement either when there are quality ones for 1/3 the price that perform exactly the same, Smitty

Anyway, back to what I was asking......basically reliability and value is what I am looking for. And to use with thunderbolt ignition on some mildly modded 509's

STEVESXM,my question to you was if you were saying that aftermarket parts were junk,and you gave a disertation about top fuel cars,and said you have raced every kind of engine combination from every manufacturor on earth,and now,after i attempt to educate you ,you feel the need to attempt to insult me,as far as being stupid,my IQ is 120 plus,so i can assure you i am far from stupid,at this point,i,and other oso members no longer have to wonder,we have your number,but please carry on,we are loving the laugh you cause with what you think is inteligence.o,and buy the way,i think you are a ignorant prik,maybe to much dope in your homeland,or maybe you were just born ignorant.best thing you can do is:7160:

I'm in a similar situation as Baja226sport and also waiting for an answer to his question.:whistle:

you could replace with the mercury coil at 73.69 each,or you could use the msd high vibration coil at 47.99 each,the msd coil will last forever and won,t need to be replaced again.from a value standpoint,the choice is simple math.the fact is both choices will performe the same,but the oil filled coil merc sells will eventually leak and need to be replaced,he msd coil contains no oil to leak out.

:bong::bong::bong::bong::bong::bong::bong::bong::b ong::bong:

:blahblah::blahblah::blahblah::blahblah::blahblah: :blahblah::blahblah::blahblah::blahblah::stooges:: stooges::stooges::stooges:

I believe stevearino hit a nerve :whistle:

You guys do realize he just does this to get a rise out of you right?

stevereno is a ignorant moron,he did not hit a nerve,i just dont take kindly to insults from a POS like him.he cant be taught anything because he knows everything,just ask him!i think he believes his own bullchit,after all ,he did say he has experiance on every engine from every manufactorer in the world.:lolhit::lolhit:he needs to put down the crack pipe:bong::stupid:

OK...sooooooo you don't like steve whoever.....got it......Will the high vibration coil from msd work fine with the merc ignition? I am sure it will work but I never gave thought to the resistance and what not that was mentioned here......

I personally have used msd boxes with nothing but bad results as far as being reliable, but if the coil is good then ok.

ya,the msd 6m box seems to be junk,i think they are importing them from china,i have replaced several leaking merc coils with the msd high vibration coil with no returns,one of them was about 10 years ago.msd has a coil identical to what merc is selling,but it is still an oil filled coil,allthough it is one third cheeper than the one merc sells,you cant go wrong with the msd high vibration coil.

Sounds good, I think I will pick up a pair!!

I've gone thru 3 MSD 6M boxes in a year ! I put the old 6A boxes that came with the boat back on. No Idea how old they are,already had them. I'm thinking about trying a 7-AL box.....maybe I'm just a slow learner. Any thoughts?

MSD .....Arrrrgh!!!
 

I just spent (2) days wringing out the wiring harnesses for the initial start of my 502 mag mpi rebuild. Darn thing wouldn't get noid or spark. Tried every diagnostic in the #23 Merc manual and finally found the problem after many tests.

Who would have thought it was a bad ignition module in a brand new MSD distributor. In order to replace the module we had to undo solder connections to retrofit a trusty GM module. A female connector, like my stock distributior, would have been nice. The MSD cap and rotor, that I quickly trashed, appeared to be of lesser quality then the good ole' Accel components that replaced them. I expected to find "Made in China" on the MSD module ....

It will be interesting to see if Summit contest my request to exchange the MSD crap for the equivalent Mallory distributor. Mallory was my first choice but had a long lead time. Maybe it would be best to ditch the new MSD coil and 8.5mm wire before I'm force to enlist Sea Tow.

Lessons learned:whistle:

Jesus, whatever happened to a good ole coil distributor combo's. Half (or more) of the people who use boxes, don't need them...

Though maybe not the best wording I generally agree, if it isn't messed up don't fix it. I spend enough money on things that actually go wrong, let alone replacing things that are completely fine. If the coil is functioning properly in a stock combination, an aftermarket one will get you no power.

Why not sell all the stuff and go HEI? EASY setup!

I agree, if you are going to spend money do something easy, I have this, all you need is the 7000 series.

http://www.performancedistributors.com/marinedui.htm