Thinking of going MSD

[86 911]

I've researched quite a bit on the MSD 6AL CD unit that I'm thinking of getting for my '78 3.0 engine. Right now my set-up is: Permatune CD unit with Bosch coil and regular black spark plug wires. So far, if I read correctly and get the MSD 6AL, I will have to additionally purchase:

1) MSD Blaster Coil
2) 8.5mm Spark Plug Wires
3) Tach adapter

I know that I will also need to do some wiring as well so:

1) Where is the starter located in the car and how easy is it to get to?
2) What brand of 8.5mm Spark Plugs would you suggest to get with the MSD set-up?

Lastly, should I avoid this project and just get a rebuilt Bosch CD unit?
Will I notice much of a difference between a new Bosh and an MSD set-up with a CIS 3.0 engine?

Also, what would be the estimated cost of this project (using new parts)?

Thanks.

[Steve@Rennsport]

Hi Matt:

A PROPERLY installed and wired MSD ignition system will make your SC run better.

Be sure to use the High-Vibration version of the Blaster coil. Thats critical since it can be mounted in any position.

Get yourself the Bentley SC manual so you know where things are on your car. Its a great investment for any DIY'er.

I like the 8.5mm Magnecor wires since they eliminate the maddeningly unreliable Beru plug connectors. I've used these since 1990 with excellent results.

If everything is properly installed and wired, and if you open those plug gaps to .040, you will be pleasantly surprised.

[86 911]

Thanks Steve! About how much do you think this project will cost me? Also, what kind of Tach adapter should I get? There are only 2 choices in the Pelican catalog: http://www.pelicanparts.com/cgi-bin/ksearch/PEL_search.cgi?command=show_part_page&please_wait=N&make=POR&model=911M&section=igniti&page=3&bookmark=14&part_number=MSD-8910EIS

[Steve@Rennsport]

I'm not at liberty to tell you where to source what you need, but see what Pelican has and shop around.

You'll need the MSD 6AL, the High-vibration blaster coil, a set of Magnecor wires, and the tach adapter. Use the one for magnetically triggered ignitions.

[Lorenfb]

A real waste of money especially for a well tuned 911SC.
Read here ( www.systemsc.com/technical.htm ) for technical info about
how CDIs work and why multiple spark systems yield little to nothing
in performance.

Porsche/Bosch designed an excellent unit that's very reliable and
more than adequate for street or race. If the multiple spark design
had any merit, Porsche/Bosch and other OEMs would utilize the
technology in a picosecond.

[no substitute]

Originally posted by 86 911


Lastly, should I avoid this project and just get a rebuilt Bosch CD unit?


Thanks.

Yes.
If there's hard data to support the superiority of the MSD I'd like to know as I'd be interested. I was interested in another brand along these lines however, and it didn't work out.

[RoninLB]

I mounted the coil on the elec panel so I ordered the Magnecore 25in coil to dizzy wire.

[fred cook]

The MSD unit is a good choice! I have the MSD 6A and MSD coil with Magnecor wires in my '80 SC and consider this to be one of the best upgrades for the money.

To answer your question about the tach adapter, you should not need one. If you will send me your email address, I will send you a wiring detail for plugging the MSD into the 6 pin master plug. Doing it this way makes the swap easy and reversable in case you ever want to go back to the Bosch CDI.

Good luck with your project!

[69911e]

Originally posted by Steve@Rennsport


A PROPERLY installed and wired MSD ignition system willl make your SC run better.

Steve: What is your experience with MFI and MSD ignitions? Are the same parts as described above required? I have heard reports it will help low RPM power/ driveability.
This is for a 2.7, E cam, MFI motor. It is not as responsive as either of my past smaller displacement MFI motors below 2.5K RPM (but fabulous above that).
Thanks, Ed Bogue

[Jeff Higgins]

In the last couple of months I have run four different ignition combinations on my '72 2.4 T MFI engine. Bosch CDI with points, Bosch CDI with a Pertronix Ignitor, MSD 6AL with points and MSD 6AL with the Pertronix. There is absolutely no noticable performance difference between the four combinations. None. I bought the MSD simply because it was available locally and I found out my Bosch box had gone bad about two days before a DE event that I had already paid for and did not want to miss.

Note that the "Multiple Spark Discharge" feature from which MSD drives its name quits at 3,000 rpm and reverts to a normal single spark. That's pretty useless on our cars. It might idle better (mine doesn't) if anything at all. I wouldn't buy one lookng for any kind of performance gains.

In the end, mine works fine. It got me to my DE and continues to work fine. Given more time, I would have gotten a rebuilt Bosch. As it stands, I'll get one some time and hang onto it for when or if the MSD goes south. Having run both back to back over a very short time period, I can say without a doubt there is nothing to choose the MSD over the Bosch. If your Bosch works, or if you can get another one that does, I wouldn't bother with the MSD. It proved a capable stop-gap for me, but under other circumstances, I see no reason to change.

[jdowty3]

I installed a MSD 6a on my SC and LOVE it. I also used the Blaster SS coil shown above. I got it new off Ebay for $50 including shipping. I was looking for a 6AL but a work buddy had a 6a ge'd let me try out to see if if worked. It did and I gave him $50 for it. No rev limiter but I don't track my car or take it past 6500 rpm anyway.
Don't get me wrong, I believe Bosch makes good electronics. But I also think multi-spark has it's benefits in regards to more efficient combustion up to 3000 rpm.
I have the 8.5 Magnacore wires which work better than the old stock wires I had and look better too.
Are you sure you need the Tach adapter? Does a 78 have the 6 pin CDI?

[Vipergrün]

I installed the 6AL in my SC and you should NOT need the tach adapter. Do your self a favor and installed male spade connectors on the wires from the 6AL and plug them directly into the 6-pin plug the OEM CDI plugs into. I posted a diagram a while back as to what goes where. This makes it VERY easy to switch back if needed. Also, I re-gapped my plugs to .045 and noticed smoother accelleration, better idle, and what FELT like better low-end, but no hard data to back that up.

[svandamme]

you might not need a tach adapter

my 77 924 didn't need one
and many other people reported you don't need one on 72 73 cars
so you 78 911 probably won't need one either

[Vipergrün]

Here's a link that shows a close-up pic of using spade connectors with on the MSD wires with the stock 6-pin connector.


MSD Ignition Install

[930addict]

I just installed an MSD 6AL on my '88 930 yesterday. It does seem to run better - the difference is more noticable below 3k rpm.

BTW...mine didn't require the tach adaptor.

[Steve@Rennsport]

If you don't open the plug gaps up when using MSD's (or any other high-energy ignition), you cannot take advantage of what they can do.

HP (on the engine dyno) and drivability goes up with wider (.040-.060) plug gaps.

[86 911]

Wow, thanks guys. There are a lot of mixed opinions about this. I'll decide what I'll do by tomorrow hopefully. About how long does the installation take?

[Moke81]

I've noticed with the MSD that it revs smoother, if that makes any sense. And I did'nt need the tach adapter.

[RoninLB]

Originally posted by Moke81
I've noticed with the MSD that it revs smoother, if that makes any sense. And I did'nt need the tach adapter.

I have a nice history with the MSD. I even installed one on a beat up smoking engine that was a total pia to start and operate. At least it started ok with the MSD and ran good enough afterwards. Years ago I would have to install them on small ocean racers that would foul plugs just crusing to the inlet.

On my current 911 carb install I'm running a bit rich on the idles and wouldn't consider not using it [34 Vent & 60 idles]. I would venture to say that the biggest bang from the MSD is if you need it to keep your plugs decent. And that if you have a CIS and notice a benefit on the street it's bonus coupons.

As far as my personal thoughts on the reliability of the MSD.. if it's good enough to take the beating of an ocean racer, good enough to last for yrs in a boat that's only operated a few months on salt water, stored 9 months out doors in a salt air world, good enough to with stand the heat of a slightly vented boat engine compartment, good enough to with stand the lousy electric system of most boats, it's good enough for me.

My install was with new oversize AWG wiring, using spade&ring terminals to a terminal block for quick R&R, keeping the MSD outside the engine comp elec panel cover, and maintaing good current feed from the starter and having the ground treminal directly against the bung ground terminal in the engine comp. Dielectric everything. The stock Ignition harness is in storage.

I posted pics of my install with info to use only as a guide, not that it has to be done my way. It's a bit over-kill.

all above is only a prejudical rant.

[Jeff Higgins]

It only took me a couple of hours to install mine. It's pretty darn easy. I put mine on the firewall just about centered between the MFI stacks. It is so much bigger than the Bosch box that it won't fit the same mounting location. Removing the air cleaner made access a snap. I have not looked that close at newer CIS cars, but it does look like access to the firewall might be a bit harder. Mounting was the hardest part; wiring it was easy. "101 Projects" even has a chapter on it.

I'm running mine with the Clewett Engineering plug wires that everyone seemed to have trouble with. Mine work great and fit very well. I increased the plug gap to .040, although you can go much wider per the MSD folks. I have heard it mentioned on this board, and some in drag racing circles that I still frequent, that the larger plug gaps might contibute to some early failures and its bad rep for reliability. I don't know that there is anything to that; just passing it on for consideration. Steve, it sounds like you have a lot of experience with the MSD; is there anything to this that you have noticed?

I also run a plain old fixed non rev-limiting rotor, relying on the box itself for that function. I run it with the 6600 rpm chip. My rotor is from a VW Bug distributor. There are two different heights; you want the tall one. Bring your rotor in for comparison and it will be obvious which of the two you need.

Has anyone done any dyno runs comparing MSD to Bosch? I'm curious because I quite honestly cannot tell the difference with my questionably calibrated "butt dyno". A lot of folks say they think it just "runs better" or is "smoother", but that is hard to quantify. Anyone have hard numbers for us?