The list of questions goes on and on. Well, I asked alot of these same questions and finally found the answers to most of my questions and narrowed my search to just two different ignitions. The CRANE HI-6 and the M.S.D. 6al. I have had a M.S.D. on a previous 4x4 and it gave me a little more power and better idle, had 0 problems with it.  After talking with several people who have, and run, the Crane HI-6 (they were all drag racers and run HIGH r.p.m. engines), two of the three had switched from M.S.D. to Crane. So right off the bat I figured if they were switching, something had to be better. after all, these are folks that bracket race and do not have lots of extra $$ to spend on stuff that will not perform.  The Crane HI-6 generates up to twelve sparks at low r.p.m.'s.  The number of sparks is adjusted to maintain a total spark duration of twenty degrees of the crankshaft rotation and about 3000 r.p.m's is a single high power spark.

Well, first of all let me tell you what I got from Crane and then we will go on to the install. I talked with a Crane Rep. and he asked me if I ever planned on running a turbo or a super charger, or if I planned on doing any heavy towing with the vehicle. They offered a Timing Retard control that you can use to retard your timing up to twenty degrees, or if you set it in the middle, you can retard or advance your timing ten degrees.  This would be a big plus on the trails with low r.p.m.'s and heavy loads from wheeling. It also gave me the added bonus of being able to adjust the timing from the cab if I should get some lower grade gas (now that NEVER happens does it!). I got the HI-6TRC ignition, it has the timing retard control that comes with it and also is Fully potted with soft Urethane for added heat, dirt and moisture protection. I also got their PS-91 in the cap H.E.I. coil to give it some added punch.

The folks at Crane Cams have a HI-6 ignition to work on any vehicle. The model I chose works for all G.M. H.E.I. systems, either in the cap coil or the remote coil. It will also work on quite a few Fords and Mopars. For the application you need visit the CRANE CAMS web site and if you have more questions after that, give one of their helpful Tech Reps. a call at the number listed on the site. O.K. on to the install...

Well, the hardest part for me was to find a place to mount the ignition computer box. I wanted to put it in the cab and that is where Crane recommends you install it. I had a hard time finding room as I have a manual tranny and can't just slap it on the transmission tunnel. I looked under the hood and still did not find a location that I really liked. I finally decided that I would gut my glove box and mount it behind the glove box door to the inside portion of the heater/air conditioning box.

I took a hack saw blade and cut out the plastic pocket that once served as the glove box (anything that I had previously stored in the glove box I put into my center console). There was not really much room for anything in the old box, so it was worth taking it out to use for this project.

Once I had the main computer mounted and ready for wiring, I had to pick a good location for the Timing Retard Control. It comes in its own housing and has 2 tabs on the top with holes for mounting. I did not want to mount it in a location that would leave it vulnerable to being hit by my knees or any of the various stuff that I have to carry in the old K-5 from time to time. Then there was the "other" consideration. I have a two year old that is in love with gadgets and switches.  He is bound to be some kind of mechanic, the way he loves to take apart anything he can get his hands on. Makes it kinda hard to baby proof a house when your baby can take apart all the child proof gizmos that you thought would keep him safe. I had to mount the Control somewhere that he could not readily see it and its bright little l.e.d. glowing away. (Its just like a magnet to him).  After toying with the idea of making a nice cut out in the dash, I got to looking at the ashtray. Flipped the door open and took out the butt catcher (I do not smoke so it is NEVER going to be used). After some measuring and checking, it would fit with some mods to the butt catcher. I broke out the old hack saw and file, cut out the back side and the little snuffer grill in the front, as well as the little divot for your cigarette. I cleaned it, painted it black and mounted it with some self tapping screws. Then I had to file the screws down flush with the top of the catcher so that it would fit back into the ash tray housing. I slapped it in and flipped it up. Perfect, and no little fingers to play with the knob on the control, not to mention the big fingers of some of my "curious" friends.

Now that the mounting was taken care of it was time for some wiring. Since I had the HI-6TRC version, it came with some nice WeatherPack connectors. The large main plug was pre-wired into the connectors and the wiring harness that attached to it was also pre-wired. I had to add the connectors (included in the parts pack) for the Tachometer, and attach one of the wires from the Timing Retard Controller. The instruction booklet that comes with both the Main Ignition and the Timing Retard Control are top notch, well written and very easy to understand. They are well illustrated and all the illustrations have numbers on them that correspond to the instructions given. If that does not make sense, here is an example (take large red wire and attach to positive battery terminal, see illustration 3a). The illustrations give you a very clear idea of what has to be done and they show all the different H.E.I. configurations. On my particular application, the unit had the added bonus of working in place of the stock H.E.I. module in the distributor.  You remove the stock module and wire the computer straight to the magnetic pick up and it takes the place of the stock module.  I will give you an outline of my wiring, but please ***NOTE*** Your Wiring May Be Different From Mine***. That being said, here is what I had to do.

The Heavy Red wire goes to the positive side of the Battery, not to the fuse box or another "Hot" wire that you have already. I found a large plug in the firewall which had several wires and one vacuum tube running through it, I took out my Dremel tool and made another small hole in the grommet and squeezed the Heavy Red power wire through it for a nice tight fit. I have a remote solenoid on my inner passenger fender so I wired it straight to the side that feeds off the Battery with the supplied ring terminal.  Crane recommends crimping the terminals, as improper soldering can make the wires brittle. I have been soldering wires and making circuit boards for a while now and was positive I could do it without making the wire brittle, so I stripped off the insulation on the terminal and crimped it on, then soldered it and used heat shrink tubing for a clean, well insulated connection. I did this on every connection I made with the exception of the 3 WeatherPack connectors.  The Heavy Black wire goes straight to chassis ground. Make sure you clean the contact area of all paint. I ran the black wire to the dash and made a small hole for a screw and nut. I cleaned the paint down to bare metal and bolted it on. There are six wires that come off the main WeatherPack plug and all but one need to be routed into the engine compartment to be hooked up to the distributor.  The exception was the "White" wire, it is used for points type ignition and I don't have points, so I made sure the end was insulated from contact and wrapped it up and zip tied it neatly in a bundle close to the connector.  There are also four other wires that come out of the main computer. A "Blue" one, for cylinder select (since I have a V-8 it was not used, so I insulated and wrapped it up as well).  A "Brown/White" wire that connects to the Timing Retard Control with a WeatherPack connector.  A "Yellow/White" wire that is used for a Stage Limit Input (like if you were a drag racer and had a line lock or a transmission brake solenoid, you connect it to set a certain "rev" limit it can be a single stage limiter by itself, or a duel stage if you already have one, just wire it to a positive switched 12 volt source). Since I do not use either of these, I insulated it and wrapped it up too.  Last, but not least, the "Green" wire that is used for the Tachometer, I connected it to my AutoMeter Sport Comp tachometer with a supplied WeatherPack connector.

Next up was to check out the Timing Retard Control and connect it to the main computer's harness. The "Brown/White" wire from the Timing Retard Control went straight to a corresponding wire on the main computer and was connected with a WeatherPack connector, as stated above. The "Black" wire goes to chassis ground and I attached it to the same screw and nut as the main computer ground. The "Thin Red" wire goes to a positive when Ignition is on location. It went through the firewall with the five wires off the main computer plug and was wired in with the "Thin Red" wire from the main computer to the H.E.I. main power wire( the one on the outside of the distributor that plugs in beside the Tachometer wire). Now there is a "Yellow" wire that can be hooked up in 3 different ways, depending on your application. I wanted to use the Timing Retard Controller as being active all the time, or what Crane calls "Continuous Retard", so I wired it straight to ground. The other two options are to a "Pressure Switch/ Relay" (to activate it at a certain boost pressure if you ran a turbo or a supercharger), or you can wrap it up and connect the optional "Map Sensor" to a supplied three prong WeatherPack connector to use as a boost proportional retard (for every p.s.i. of boost, the retard control will automatically retard the ignition the same amount up to 20 degrees depending on how far you have it turned). Since I do not have any use for the "Map Sensor" either, I insulated and wrapped up these wires as well. After these were connected and routed inside the dash, it was time to get the six wires left over into the engine compartment. I found a plug in the fire wall that was right below my oil pressure line. I removed the plug and used a small rat tail file to enlarge the hole a bit. Then I took a rubber grommet and placed it into the hole to protect the wires from cuts and grounding out on the chassis. A good tip for fishing wires through the fire wall is to tape them tightly together in a nice straight group. You can also taper them if you like, tape each wire about 2 to 3 inches behind the next so that you kind of get a wedge shape, making it much easier to pull through the grommet. I also lubed up the wires with Windex to make them slide through easier, it evaporates and does not remain slippery or sticky.

Once inside the engine compartment, the "Thin Red" wires from both the main computer and the Timing Retard Control were put together and connected to the factory H.E.I. main power wire. The other four  wires go to the distributor. You also have to make a short ground wire that goes from the H.E.I. coil ground to the inside of the distributor.  (More on this in just a few lines). First thing I had to do was remove the Distributor cap and all the wires attached to it ( the power and ignition module wires).  If your spark plug wires are long enough (mine were, thank god!) you can leave them attached and just move the cap out of the way.  Since I had the Crane H.E.I. PS-91 in the cap coil, I changed it out at this time as well.  The stock coil was coroded and in need of replacement anyway. I pulled the cap off the coil by removing the two screws that held it down and then removed the old coil by removing the four screw that held it in place.  Installation is in the reverse order, (they include directions if you can't remember which wire went where after you get it out), nothing to it.

Next I removed the stock ignition module and cleaned out the distributor.  Once the stock module is out you can hook up the rest of the wires and your almost ready to fire it off.  First of all I had to make a short ground wire to go from the outside of the distributor cap, it and the "Black" and the "Orange" wire that are inside the black plastic tube are hooked up to where the outside plug of the stock ignition module went.  The "Orange" wire goes to the positive coil prong, the "Short Black Ground" wire goes to the middle ground prong then into the distributor and grounds to the stock grounding screw inside the distributor.  The "Black" wire in the tube with the "Orange" wire goes to the negative coil prong.  Now that these are hooked up, you take the "Short Black Jumper Wire" and the "Violet" and "Green" wires and run them through a small rubber grommet into the distributor.  The "Short Black Ground" wire goes to the stock ground screw as already stated, the "Violet" wire goes to the "White" wire on the magnetic pickup plug.  The "Green" wire goes to the "Green" wire on the magnetic pickup plug.  Then you take some small plastic wire clamps and, using the stock ignition module screws, attach the wires to the distributor so they will not interfere with distributor function.  Next, double check all your wires to make sure they are connected properly and that they will not get caught in any moving parts.  Put the distributor cap back on and fire off the engine.

Once everything is running properly, you can shut down the engine and set the Rev-Limiter switches.  There are two rotary dials that you turn to set the rev-limit at your desired level, any where from 600 r.p.m.'s up to 9900 r.p.m.'s at 100 r.p.m. increments.  The dials are located on the end of the computer where the wiring harness comes out.  The one closest to the harness does the 1000 r.p.m.'s and the next one does 100 r.p.m.'s.  For example, if you set the first dial at three and the second dial at two you would have a 3200 r.p.m. rev limit.  Since I have an older motor and I do not rev it too much, I set my limiter at 4600 r.p.m.'s.  The Rev-Limiter is a digital sequential rev-limiter.  If you over rev the engine and reach the rev-limiter, the cylinders are then fired in an equal rotation to prevent plug fouling and minimize harmonics and vibration until the r.p.m.'s fall below the rev-limit.  The computer also has some on-board diagnostic features so that you can test for problems if you have any.  A l.e.d. blinks a code and there is a list to refer to in the instruction manual.  It also has a Tach Test feature that allows you to test your tachometer before you crank the engine to make sure it is compatible with the computer. If it's not,  the instruction manual lists the reasons why it may not work and remedies for them.

I was very impressed with the products I received and I can now tell a "seat of the pants" difference in the power of the engine.  It is by no means an astronomical difference in horsepower, but it can be felt.  The engine also starts much quicker, idles smoother and  pulls much lower in the r.p.m.'s without the bucking you normally get if you try to make an engine pull at that low an r.p.m.  It has made for much smoother wheeling with less rock slippage because of being able to run at a lower r.p.m.  If you are looking for a good aftermarket ignition to give you good reliable performance, Crane Cams has your answer!

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