Aftermarket electronic ignition???????

[speach]

Today I picked up a crane cams Fireball electric ignition box. I am interested in putting this on my 68 Cadillac.  I also have a HEI dist from a later 500 that I plan on using. Anybody have any insight of the advantages/disadvantages of using this electric ignition box?

Thanks

[TJ Hopland]

It looks like its very similar to the MSD 6 ignition box.   I picked up one cheap (mds 6) at a garage sale or swap.  It sat on the shelf for a while till one day I was having points trouble in my boat which has a chev inline in it.  Its a slightly odd application so there is not tons of electronic distributors sitting in junkyards.  I happened to look at the msd box on the shelf and thought what the heck, I should try it.  I did not read the instructions for the fireball but the MSD will trigger off points so that is how I set mine up.  It starts easier.  Idles smoother and the off idle acceleration seems more positive.  Only thing I have had to do is if it sits for extended periods I have to run something like a dollar bill between the points to get it going.  This may be due to the quality of the points I have on there.  I got a set of blue streaks but have not got around to installing them yet.  Tinkering with the points I learned the hard way to be sure you have the key off when you are messing around there.  That multi spark discharge bits hard!    I assume the fireball will trigger off points or the HEI.  With the MSD they have optional cable assemblies to make it easier to hook to the common ignitions like HEI, Duraspark and such.   I really like it on the boat.   I was not so excited that I ran out and bought more for my cars. 

A HEI distributor sometimes has minor clearance issues with the smog cross over tube.  I have installed them that clear fine and others need a slight tweak.   If it needs tweaked its very slight.  I think I just took a 2x4 and a hammer and gave it a couple whacks.  It does not take much.  If you look close before you install the distributor you can see its bent but once installed you cant tell.   The HEI uses different wires than the points style so if you need wires anyway no problem but if you have good wires its an additional expense.   If you still have AC and its the original dual belt system the belt clearance is very close.  I am told that you can find a orientation and timing setting that it will just clear but I imagine this could get to be frustrating because there is not a lot of options for the way the distributor sits with the AC compressor installed.   If you don't have the AC installed then there is no problem, you use a shorter belt that just goes from the crank to PS pump.  The factory HEI cars changed to a single groove AC PS belt.  This requires the matching crank pulley and AC PS pulleys.   If you are thinking about doing all this may be a good time to look at finding a pulley set that will allow you to eliminate the smog pump.  Its not a performance problem but can be a hassle to maintain and without changing the pulleys its the only way the water pump and alternator are driven so it becomes a critical to have working item.   The non smog setup has a different crank pulley that the front groove is spaced out further to align with the alternator.    70 was the most common year to not have a smog and have the dual AC PS setup.  75 and 78 are common years for a single groove non smog setup. 

Points system had 2 + wires on the coil.  One came from the starter solenoid, its 'live' when the starter is cranking.  The other is the power that comes on with the key.  Its fed through a resistance wire.   Not sure exactly where in the line the resistor wire is but in theory it should be removed or bypassed when installing an HEI.  My 73 still has it and has an HEI installed by a previous owner and it seems to work fine with the resistor still in place.  Its been on my to do list to figure out where it is and remove it but have not got around to it yet in the last 10 years.   

[speach]

Thanks a bunch! Not sure when I get around to doing all of this but, it's nice to know things before hand. I have gotten rid of the smog set up by gutting the pump, so no worries there. I do plan on setting up the AC at some point, but not top on my list. Thanks for the insight on the 75 and 78 pulley set ups. I will be on the look out for those. So overall you think the ignition box would only be a plus?

[Dave Shepherd]

If possible I would choose a GM HEI one wire set up, coil in cap, very reliable and more than enough spark for the Cad engine, MSD has proven to be somewhat unreliable in some of the race cars cars I have run.

[walt chomosh #23510]

William,
  I'm with Dave on aftermarket additions to your Cadillac. A MSD distributor failed on my son's 5.0 Mustang in the middle of the night halfway between Tulsa and Dallas.(had approx 150 miles on it!) I also had a MSD 6 ign box fail on my 1955CDV....they(MSD) repaired both units but who needs road failures? I suggest using a genuine GM distributor that will fit your application.....by the way,both the 5.0 distributor and MSD ign box are sitting in boxes in my attic.....walt....tulsa,ok

[cadillactim]

As stated earliler, the HEI is reliable, and parts are easy to come by.  The drawback on the 68-72 engines is the double pulley on the compressor.  One of the belts will have to be removed to clear the HEI distributor cap.

Tim

[speach]

Thanks guys. As previously stated I plan on using a later model 500 HEI dist that I have. I have heard bad things about aftermarket distributors not working out so well too. My main question was about the ignition box, from what I understand it will get me better fuel consumption and mileage. Correct me if I am wrong. Tim do you happen to have any Nice 67 coupe door panels down there? Dont have the money now but just curious. I just picked up some rear conv panels.

[cadillactim]

I don't have any good 67 door panels, as I mainly rebuild parts now.  Tim

[Gene Beaird]

Like others, I've seen problems with aftermarket ignition boxes.  Most of the issues appear to stem from them being installed under the hood where the box sees wide swings in temperatures, and extreme heat and moisture.  If you can, put the box in the passenger compartment (ie., in/behind the glove box), and try to wire it so you can bypass it when it fails. 

We're using a MSD6 in our C Prepared autocross Firebird, and the box is bolted to the inside of the firewall.  It's fired by a dual-point distributor that's sporting only one set of points.  In the 10-12 years we've run the car, the box has been pretty reliable.  I attribute that to keeping the box out of the engine compartment. 

[cadillacmike68]

William,

Why bother???  The 68-74 GM P&C ignition works great, its easy to adjust while the car is running and unless you plan on revving the 472 to over 6,000 RPM, it is more than capable. I would just replace the P&C and get a good set of Delco wires first before doing anything else. I've had these cars for over 24 years and that is one of the least troublesome parts of the car. A cold or slightly warm engine start is usually less than 1/4 second on my car.

[TJ Hopland]

For those that don't have a few hundred bucks for one of the fancy boxes but wouldn't mind a slight improvement:

Here is a site with some good info and options.  http://www.gofastforless.com/

After reading that I did some searching and found this diagram.   I have this setup on a few small engines and it seems to work well.  I did not bother with the bypass switch because these engines don't go far.  I did do the LED and added a second LED to indicate power to the module. They are very handy indicators to tell if you are getting power and signal to the module.  Early on in my projects I had some issues like crap quality points and other wiring issues with the rest of my rigs.  Finally went to Standard Blue Streak brand points and have not touched them in 3+ years now.   I don't think it notes it in the diagram but the module needs to be mounted to a decent heat sync and use the white heat transfer grease.  I have seen it done with simple aluminum bars.  Heat syncs for computer CPU's also work well if you have junk computers or a surplus store around.   On my Harley golf carts I mounted them to the metal fan shrouds.  The ground connection is also through the body of the module, usually one of the screw holes so keep that in mind when mounting.

[cadillacmike68]

I still have more faith in the GM OEM P&C coupled with a Crane Cams adjustable vacuum advance kit.