Howdy,

Let's start with the dumb question:

I understand that in a standard system you have a coil and the distributor. In a MSD system you still have the coil and distributor, but you also have the additional box (i.e. the 6AL seems to be popular). What exactly is the function of the box?? Based on what I can read on the MSD site it is a capacitor:

"It draws its energy directly from the battery where a custom wound transformer steps it up to over 460 volts. This voltage is then stored in a capacitor until the ignition is triggered. At this point, all of the voltage is dumped into the coil where it is transformed into even more voltage, anywhere from 30,000 - 45,000 volts depending on the coil, which is sent to the distributor and finally to the plugs."

Secondly, is there really sufficient improvement in spark/idle/performance/startup to justify the cost of an MSD system for street applications?

According to the blurb on their site:

"The payoff is complete combustion of the fuel mixture which results in more power, increased throttle response, a smooth idle, quick starts, improved economy and reduced plug fouling."

I'm surprised they don't claim that it makes you a hot breakfast when it's not busy healing the sick!!

At this point it's just idle curiosity more than anything else. I know that asking ignition related questions will result in a thousand opinions and occassionally bloodshed, but I look forward to hearing the opinions.

Cheers
Craig

And they give you the option of multiple rev limiters for compertition use.

I don't understand why anyone would use anything but megajolt computer and an Ford EDIS (electronic distributorless ignition system) from a mondeo or similar,
Complete for less that $300. For EFI go megasquirt. No dizzy to stuff up, all components are cheap, reliable and available and it's fully programmable. I'm running a turbo 1776, tried several dizzy set-ups, all failed because they couldn't eliminate detonation while maintaining any sort of bottom end power. I had to run a programmable computer to tailor my ignition curve to exactly were I wanted it I've been running this for 18 month and bless it every time I start the engine it's just so smooth, absolutely no dizzy scatter. The mega jolt system is the best value for money ever.

Have a look at these links

For the EDIS http://www.ebay.com.au/itm/EDIS-4-Ignition-Module-Ford-Kit-36-1-VR-Coil-Megas...

For the Megajolt http://www.autosportlabs.com/megajolte-p-41.html 

Cheers Ian

When I built my 550 Spyder replica, the engine that I fitted was a 911 T, with Weber carbs. The engine ran really rough, and was down on power, even after a lot of tuning.

Mark Poole gave me a lot of help with the engine re-build, so I called him for some advice on the problem. Mark did not hesitate in suggesting that I fit an MSD........That fixed the problem immediately. Evidently those early engines don't like modern fuels.

I saw a brilliant MSD tutorial on a TV show on Bris 31 called Gasoline.

It was the best dam car show i had seen, so technical and went into the nitty gritty compared to yea this a is a ferrari, yea this is the catalogue specs, lets pull some skids (TOP gear etc). No, it had actual bulk raw up front substance.

The MSD ignition compared to the normal coil/spark discharge was excellent, with the demonstator showing that usually after about 4000rpm, poor spark and the occasional misfire was to be expected in the stock system, while MSD maintained a constant bright bang throughout, till 10,000 rpm i think it was?? or maybe 12,000 rpm.

They had another MSD style ignition system they demonstated for alcohol filled drag cars, good for 20,000rpm or sumfin rediculous, and the dam crazy spark extended and looped out the side light bloody lightning! lol.

Dam i wish i had a copy of that segment though. Was straight no frills facts of 'here it is' and let me flick the switch and just watch and see for yourselves. No garbo

Heres an american demo, not as good as what i saw but gives basic idea:

http://www.youtube.com/watch?v=DT2clNrxOuM 

Hi

I fitted a 6AL digital to my sons bug, it runs so much nicer. MSDs do have a reputation for being unreliable, keep the car wiring so that it can be returned to stock easily

What attracted me was the rev limiter.

There is a locally made unit that is getting rave reviews by the yanks http://www.iceignition.com/ 

Steve

I know MSD's are good but I have heard mixed reports on them working, I think the gringos boys might of had a few issues with 2 out of 3 being no good.

that fella from South Australia with the white hillclimb bug has a 009 hooked up to a CDI box I forget the brand but at the supersprint he said he had good results. I think he called his motor "china-black" becasue he used all the chinese VW parts and heat treated them all before use.

Cheers

Shaun

we just run good old points in our drag car stan motor
good for 20000miles.
no tacho
No rev limiter
just rev it until it wont rev any more

http://www.youtube.com/user/avwnut#p/u/3/CW1lMnVgV4I 

http://www.youtube.com/user/avwnut#p/u/47/Ah2AZ1-FxeI 

The CDI box the hillclimb bug used was a Crane Hi-6, about $300 or so.

I would highly recommend MSD set up.
I have one in my 2165cc Single Cab. (Distributor, 6AL, Blaster coil)
The improvement on idle is significant. The timing light is so steady at revs compared to a 009. (i.e. a single reading/line not a blurr like I have seen on a few 009's I have used)
The advance curve is easily adjustable via a combination of springs and toal advance limit bushing.
Changing the advance curve with the MSD distributior is a 5 minute job including resetting the total advance with timing light.
They are really very simple and very effective.

I loved my 6AL, and if you get an MSD, it is well worth it just for the rev limiter.
It was 20 years old when i purchased it second hand...never a problem.
I recently upgraded to a Power Grid 7 and now a crank trigger.
It is fully programable and has twice the spark energy of the 6AL.

Like most ignition upgrades, the start and idle quality is usually improved.
If you like to run your engine rich or lean from ideal, they can usually improve the burn quality.

I think if I was to suggest an MSD unit for others,
the 6Al2 would be my choice.
All the nice features, easily adaptable to any dizzy trigger system and quite affordable.

This is out of control:

http://www.youtube.com/watch?v=DNuy_RxLW4A&feature=related 

Yep, worth it if you can afford it. Best system available IMO. Fitted a 7 series digital recently and with the built in dial adjustable rev limit and two step limit, they are fantastic. The driveability below 3000rpm is definately improved, generally rejetting also required with carbs.

what ^ said !

Thanks everyone.

I'm actually surprised by the overwhelming positive response. I need to do some more reading and learning before I take the leap.

Whilst putting in an engine I figure I might as well kill as many birds at once that I can afford.

Cheers
Craig

Well did a teeny bit more looking about the Compu-fire and found these:

http://www.compufire.com/index.php?option=com_content&view=category&l...

and also funnily enough:

http://forums.aussieveedubbers.com/viewtopic.php?tid=84897 

I think on that basis I'd be better sticking with the MSD for now, and then rethinking later if I go EFI, whereupon I can reuse the MSD on whatever I buy for my second toy.

if you go for EFi, get some GM coil packs. those things are 60Kv ! its cheap as chips and can be ripped of any VN and up V6 engine.

Like any electrical component, if it gets a voltage spike they don't like it ,
just make sure that your vw electrics or all good.
Rod penrose sells compufire.
we have had one on roses car for over 25000Ks

If it's spikes your worried about, it's a filter you'd need. All electronics are subject to reliability issues. I've had more drama's with Compufire than MSD's.

Any comments on the MSD vs Mallory debate?

This looks really nice:
http://www.compu-tronix.com/DIS4009.htm 

In my ride I have an old Jaycar HEI KC5247 with dwell control + compufire points replacement module for triggering + Second hand Omex Clubman soft rev limiter.

Rev Limiter

http://www.thesamba.com:80/vw/classifieds/detail.php?id=540417 

I have had Compufires on the 009 in my 1916 for at least 200,000km - the only problem I had was when the first one stopped working when some stupid bald bastard (me) re-connected it up the wrong way around. :-(

Yeah, I've had many many miles out of a compufire. Also sell them still today. But occasionally they do fail. Sometimes it's not the electronics fault, we had a bad connection at the fuse box cause a unit to fail, the car still ran, but would stop too !!!! Not always at an appropriate time! That's the biggest issue with any electronics, they don't always let you know when they are about to cark it, and it can take literally hours, days or weeks to correctly diagnose some ignition issues.

OK comparing a drag cars ignition requirements to a street car is irrelevant. The drag car only needs accurate ignition at full revs and full load a magneto does the job.
A 009 (the most evil thing out there) being centrifical only has no way of adjusting for load. Put your foot down or climb a hill the dizzy has to catch up as revs increase. I have a stock 67 that will stay original I mean points and original dizzy and a pict30-1 and it will stay that way, if you change to an electronic module it's not original hence go the whole hog. Anything performance oriented ie high compression high revving you need to compensate for lack of lead and low fuel octane. If you want the best get your head out of the last century and get rid that dizzy. Also if I can fit EDIS so can any trained monkey, yes it's that simple and I can return back to stock quicker than it would take to remove your compufire and refit and set your points. Yes I have used compufire, yes, cleaner spark but no real benefit when it comes flexibility there is none. As far as changing weights and springs to change the characteristics of the dizzy how do you adjust +or- over a narrow rev or load range without affecting everywhere else?
PS EDIS has a 10 degree fail safe if there is a total computer failure so you will get home.
PSS I set my plug gap on the EDIS at 40thou/1mm and there's plenty of juice to jump at lest 60thou