HEI Ignition Conversion

FreeBeeTony

Captain
Joined
May 15, 2002
Messages
3,991
I am currently rebuilding a '67 Mercruiser 160 and want to convert to an HEI ignition. I have a coil with an internal resistor for the new HEI distributor, so I don't think I need a ballast resistor. The coil is not in the cap, it's seperate. Does this mean I only need 1 wire from the key and not one from the starter solenoid? This is how I understand the "old way": when the engine is started, the coil gets 12V from the starter solenoid, once the engine started and the key is released, the voltage now going to the coil is ~9.5v going through a balast resistor. Being that the new HEI coils have internal resistors, I am thinking I only need 1 wire from the key to supply 12v and another for the tach. Does this sound like I have a good understanding so far?
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
70,468
Re: HEI Ignition Conversion

Ya Tony, you're on the right track.... No need to come all the way from the key though... there Should be Key Controled power At the motor.... Usually a Purple wire.....
 

FreeBeeTony

Captain
Joined
May 15, 2002
Messages
3,991
Re: HEI Ignition Conversion

Thanks bondo, I am rewiring the entire harness. It's just as easy to come from the key.<br />Now for another question: what about the shift interupter? Does this get connected to the 12v wire coming key or after the coil? Also, does the distributor need to be marine? Being that it is electronic ignition I wouldn't expect to have any open spark like the points ignition.
 

snapperbait

Vice Admiral
Joined
Aug 20, 2002
Messages
5,754
Re: HEI Ignition Conversion

FreeBeeTony, I don't know about you shift interrupter, but you definately NEED a marine distributor even with your electronic ignition, as there is still and open spark jumping from the rotor to the terminals in the cap..<br /><br />Gases also build up from the "electrical storm" inside the distributor cap, which must be vented... On a marine distributor the holes in the distributor housing that allow the gases to escape are covered by spark arrestor screens which have very fine mesh allowing the gases to escape, but not allowing a spark to pass thru... ;)
 

FreeBeeTony

Captain
Joined
May 15, 2002
Messages
3,991
Re: HEI Ignition Conversion

Thanks snapperbait, does that mean that just the distributor cap is marine or the entire distributor?
 

FreeBeeTony

Captain
Joined
May 15, 2002
Messages
3,991
Re: HEI Ignition Conversion

Any ideas where I might find a marine HEI distributor for a IL6?
 

JasonB

Lieutenant
Joined
Feb 10, 2003
Messages
1,449
Re: HEI Ignition Conversion

If your original distro is still good, it may be worth investigating a Pertronix conversion kit. I installed on in my Merc this weekend. Although it hasn't been on the water yet, running on a hose in the driveway I am very pleased. Can't wait to see what happens under load. If all goes well, It will have been $150 well spent. I used an Ignitor II and a new Pertronix epoxy coil.
 

FreeBeeTony

Captain
Joined
May 15, 2002
Messages
3,991
Re: HEI Ignition Conversion

I looked at the old distributor and can't find anything special about it, what does the kit consist of? Where did you get the kit? Online?
 

JasonB

Lieutenant
Joined
Feb 10, 2003
Messages
1,449
Re: HEI Ignition Conversion

The kit for mine included a replacement breaker plate with the electronic ignition attached, a new rotor, and a magnet sleeve that the rotor sits in. I also opted for a new coil as my original is nearly 30 years old and was very weak. The new ignition has the capability to fire 40k volts. Installation is easy now that I have it figured out. The conversion essentially involves- remove cap, remove breaker plate with points still attached, drop conversion kit in per marks on plate, install new wire grommet in the distributor and connect the new 2 wire ignition to the coil. If you have a resistance wire like I do, you will want to bypass it, but you will have to do that for the HEI anyways. Took about 45 minutes to install because my coil is a pain to get off. I'm happy so far. Total cost was: Ignitor II module -$100, Flamethrower epoxy coil -$40, free shipping at www.vintagperformance.com . Carl was very helpful in selecting what I wanted and needed. You can get a more basic conversion for $70. The big difference is the II is a little more intelligent. It adapts the dwell to current needs and also has a power disconnect to keep from frying anything if you accidentally leave the key on. Sierra/Aqua Power also markets a kit that is carried through many online e-tailers and I think I have seen some in the Marine Mega-Mall here. From the looks of them, I think they are rebadged Pertronix kits, but that is a guess on my part. I believe the Pertronix will save you some cash and get you what you are looking for over the HEI. <br /><br />Pertronix is very helpful in selecting the right kit and helping if you have problems installing it. Their number is - PerTronix Tech Dept. at 1-800-827-3758 if you want to call them with questions, give them your distro info and they will give you the part number to order. You can also shoot Carl at VP an e-mail from his website.<br /><br />My 302 purrs like a kitten now at the idle RPM it should. That didn't happen with the old points for some reason. I haven't tested her on the lake yet, but hope to Saturday.
 

FreeBeeTony

Captain
Joined
May 15, 2002
Messages
3,991
Re: HEI Ignition Conversion

Thanks Jason for the info. I opted to purchase a Pertronix conversion kit from Aftermarket Discount Marine Parts. I don't know if its an Ignitor II. With a coil, cap, rotor and wires it ran me ~$110. Thanks for the advice. Now I have to return everything else I bought that was automotive. Now for the next question: I have 2 distributors and want to make sure one of them is marine. One has 2 openings on the bottom with screens over them. Is this the marine distributor? Both have Delco P/N's.
 

f_inscreenname

Commander
Joined
Aug 23, 2001
Messages
2,591
Re: HEI Ignition Conversion

Did mine Monday night. Started about 7:30pm and it gets dark about 8:15 and had time left over to driveway test it. Never herd the starter engage before the motor was running (after the boat had not been started for a week). That has never happened with the points set up. Not even with a Mallory duel point dist. Went out today and it ran so well I didn't even bother to tweak it out (with the change over I can now set the crab and timing right). Time limits prevented me from doing so today but the next time I out I am sure I can almost reach near perfection on this ignition thing. After the last two years of screwing with points it will almost be like nirvana.<br /> As for removing your resistance wire, read the directions, mine said if I had one to leave it in place. I am sure they all install a little different
 

JasonB

Lieutenant
Joined
Feb 10, 2003
Messages
1,449
Re: HEI Ignition Conversion

I would GUESS the one with the screens is the marine. I would also bet that your kit will be the standard Ignitor. It is a good unit and the only reason I paid the extra for the II was the auto shut off feature. I've mistakely left the key on for a while due to moving the trim in the driveway.<br /><br />Good call on the new cap and wires. The pertronix kit will likely have a rotor, but I was unable to use it as it had too much play on the shaft and its electrode seemed to be a bit too long. Then again, I have an odd prestolite distributor. A standard rotor works fine on mine even with the Pertronix's magnet sleeve.<br /><br />On a side note, Hey, F_in, how's the S'nova these days?
 

f_inscreenname

Commander
Joined
Aug 23, 2001
Messages
2,591
Re: HEI Ignition Conversion

Hay JasonB <br />Just fine. Was out today. The best it ever run, if I could just stop hitting floating stuff. Not much time to react at 65mph. Think I will be on my way to the prop balancers soon. I wanted to cup up a size or two anyway. After 27 years of owning boats (my first was row boat when I was 7) this 31 year old boat is my favorite by a long shot and I still have not seen a better made boat yet.
 
Top