HEI ignition in nailhead?

[cobravii]

I saw an HEI distributor on eBay and I am wonering what it takes to convert to HEI.

Is it just a matter of dropping in the distribuor, supplying a power scource and changing plugs?

[Guest pfloro]

Hello cobravii:

What is your reasoning for this conversion?

I'm not familiar with potential distributor clearance issues on the nailhead. But...

If the HEI distributor will physically clear everything around it AND the shaft length/mounting setup is the same as the stock distributor, then supplying a +12V 'ignition on' supply is the basic requirement. Of course, you must transfer the source for the vacuum advance to the HEI distributor. More modern plugs with a wider gap (~.060") might reduce emissions & improve economy.

IMHO: I would leave the stock distributor and simply upgrade to a Pertronix 'Ignitor' electronic ignition system (follow link below). The conversion is invisible except for an extra wire exiting the distributor. The Pertronix simply replaces the points & condenser. You can keep your existing ignition coil too. They are very reliable units. HEI won't buy you anything over the Pertronix. A pre-emission controlled engine doesn't really benefit from the higher secondary voltage which HEI provides. Again: IMHO!

Pertronix

Paul

Edited February 22, 2010 by pfloro (see edit history)

[cobravii]

I want to switch to HEI simply to get away from points. I don't want to have to fiddle with dwell etc and would like better performance along with easier parts availability.

The distributor I saw on ebay was a nailhead distributor converted to HEI.

My car is a 1964 Buick Electra convertible with a 425 and dual 4 barrels. I think there is plenty of room.

[Guest pfloro]

OK..., I understand your reason for the conversion and your reasoning is sound...! IMHO, getting away from points is a good thing.

HOWEVER:

The distributor I saw on ebay was a nailhead distributor converted to HEI.

This makes me more than a bit nervous. I'd be concerned that this 'conversion' is 'Rube Goldberg' (convoluted & non-standard).

Take a look at the Pertronix Ignitor upgrade. You know the state of your present distributor. The Pertronix upgrade simply substitutes a solid state module & reluctor for the existing points & condenser. That's it...!

Others on this forum will attest to the beauty & reliability of the Pertronix Ignitor. I've had one on the '66 Mustang for 10 years and it's been flawless.

Fast starts are the rule in any weather and the timing never changes.

Paul

PS: I don't work for Pertronix but I support sound technology...!

PPS: I just looked on ebay & saw the 2 red capped 'Nailhead HEI' distributors. This is the standard GM HEI design used from about 1975 - 1980 (before Computer Command Control). They are certainly NOT converted Nailhead distributors. For that price, you could buy 3 Pertronix Ignitor units...!

NAILHEAD HEI DISTRIBUTORS

Edited February 23, 2010 by pfloro (see edit history)

[cobravii]

I looked on the Petronix site that you reccomended and found it confusing. i wasn't sure what I should be ordering.

The other thing that crossed my mind is if I have problems with the Petronix set up, where do I go for parts quickly where as with the GM style on eBay I can go to any parts store for parts.

Do you know a part number in Petronix that I should look at and is there anywhere I can get replacement parts in a hurry if I need to?

Thanks for the info... much appreciated.

[Guest pfloro]

Additional thoughts & information:

With the GM HEI distributor, parts will be available anywhere. The HEI unit has a module, pickup coil & integral ignition coil. These replacement parts are inexpensive as thousands (tens of thousands...?) of HEI units are still in operation.

Consider the initial cost of the new ebay HEI unit.

The HEI's mechanical & vacuum spark advance curves would most likely need to be tweaked for your nailhead engine. Your stock distributor is already properly 'curved' for that engine.

Are you concerned about maintaining a stock appearance on your nailhead?

Pertronix has been around for some time & I suspect replacement Ignitor modules will be available for years to come. As a backup, you might carry a set of points & condenser in the car along with the simple tools needed to swap in case of an Ignitor failure. Some folks (like myself) carry a spare Ignitor module in the car. I've never had to use it...

If your car will not be a daily driver, a set of points & condenser (as backup) should be more than enough. The Pertronix Ignitor is at least as reliable as the GM HEI module (the most likely part to fail). I understand that 'off shore' HEI modules (even in a Delco or Standard Blue Streak box) are questionable.

*****

I checked the Pertronix site and you only need the basic IGNITOR I unit. Scroll down to find the application for your Buick. They show two different IGNITOR I part #s: 1181 and 1181LS. I would call them to find out the differences (I suspect either would be fine)...

IGNITOR APPLICATION GUIDE

Hope this info helps guide your decision.

Paul

Edited February 24, 2010 by pfloro (see edit history)

[Bhigdog]

I have Pertronix units in all 6 of my collector cars ranging from a 39 Chev stovebolt 6 to a Vette 427 big block. The longest has been in for over 10 years. I haven't had any problems whatsoever (knock on wood) and there is near zero ignition maintenance. The units are readily available from many vendors and I'm certain you could have one at your door the next day, by Fedex, if you really needed it................Bob

[cobravii]

Ok, you guys have convinced me..... Pertronix it is!!!

Now, there are two part numbers ... 1181 and 1181LS. The info tells me that LS means lobe sensor. How do I know which one I need for my 425.

Thanks for all your help guys!! Really appreciated.

[Guest pfloro]

Great...! You won't be sorry.

I did some additional research on the Pertronix site. With the 1181LS, the existing cam lobes in your distributor trigger the module to switch the coil primary voltage (just like the points). The 1181 uses (I believe) a plastic ring which fits over the cam lobes. Within this ring are 8 tiny magnets which trigger the module. This is the type which I have in the Mustang.

I would spend the extra few dollars for the 'LS'. It has fewer parts. You might want to 'play dumb' and ask Pertronix about the difference...

If you scan the application guide, you'll see that the 1181 or 1181LS is used across many GM divisions from '57 - '74. They all basically use the same Delco-Remy distributor...

Keep us posted,

Paul

PS: How about some pictures of your '64 Electra Convertible? Nice!

[RivNut]

Pertronix is okay as long as there's absolutely no "play" in the bushings on your distributor.

They have been known to leave folks stranded. Most of the guys I know who are running a Pertronix keep an OE distrbutor in their trunk.

Google Dave's Small Body HEI and see what he has to offer. Your OE distributor with OE HEI parts that can be purchased from any NAPA, AutoZone, or O'Reilly's. IF, and it's a big IF, you ever have trouble, help is as close as the neaest town rather than waiting for delivery of special parts from the manufacturer.

At least look it over before you make a commitment.

Ed

[Guest 40series]

I have points and pertronix. Both have never left me stranded. If you have a matchbook in the glovebox; points will always work.

[Guest kaycee]

I agree with going to a Pertronix. I installed one in a '65 Riviera 425, and never had a problem with the installation or operation of the car afterwards. As was mentioned, make sure your distibutor is 'tight'(bushings are good), and it's a quick installation if you follow instructions on installation, including distributor shaft end play adjustment ( just remove the drive gear and install a thrust washer (furnished with the Pertronix) if you need to after measuring the shaft end play). It's never a bad idea to have a spare point type distributor as a spare if you have doubts on reliability.

kaycee

[Wmsteed]

I have used the Pertonix ignition conversions for years in everything from boats to various cars.

The one thing you have to be careful about is to make sure you use the right module and correct coil. I usually call Pertronix tech line and get the correct application for the vehicle I am working on.

The only trouble I have ever had with the Pertronix conversion is because someone did not follow the directions that came with the unit.... Bill

[NTX5467]

Regarding shaft bushing wear, every points-style distributor I've put points in has had some side-play at the rotor end of the distributor shaft. I suspect this is from the side thrust put into the shaft by the points spring. The first factory electronic distributor I put a cap and rotor in (a '72 Chrysler factory electronic distributor) had NO shaft side-play, which led me to believe that the contact spring of the points was what was wearing the bushings. So, when you get the distributor out and cleaned-up internally (think "disassembled and cleaned, oiled, and reassembled), check the existing side-play against factory specs.

The other issue with point-style distributor cam lobes is WEAR and original machining accuracy. If you get a dial indicator and, as I was going to do, use that to set the point gap, you'll probably find a wear groove where the rubbing block of the points contacted the distributor cam lobes. With that wear, the specified point gap and resultant dwell may or may not be in the middle of the factory specs. The wear was visible, but it varied from lobe to lobe, even minutely, which would affect point opening and closing points . . . or in the case of the Lobe Sensor, each cylinder's spark timing. With the dial indicator, it was all right there on the meter's face. Having seen this, it would just mean that a Lobe Sensor system would not improve on the existing distributor's cylinder-to-cylinder timing accuracy, but would improve upon the other things which electronic distributors have for improvements over point-style ignition systems.

As I recall, the ACCEL electronic distributors mimic the design of the earlier Chrysler distributors, but I don't know if they have those for Nailhead Buicks.

Davis Unified Ignition has conversion distributors using GM HEI components adapted, extenally, to existing distributor bodies. Looks kind of "different", definitely not "stock", but it expands the good points of the GM HEI system to other brands of vehicles.

Even with the inaccuracies of the distributor cam lobe wear issues, do make sure that all of the distributor shaft bushings are "in spec" or take the trouble to get them replaced during this conversion process, for good measure.

Just some thoughts,

NTX5467

[cobravii]

So with the wealth of kowledge on this forum I went ahead with the 1181 Pertronix kit and a 40 000 volt pertronix coil. I am in the process of reassembling my 425 and have just finished overhauling the dual quads.

My question is: with the new module and coil.... what do I do for sparkplugs?

[NTX5467]

Usually, the heat range of the spark plug has no relationship to the type of ignition system firing them. In some cases, though, you might be able to go a heat range or two colder as the hotter plug might have been there to keep things cleaned up on the plug's insulator so that it would work well with both lots of time idling around, followed by a quick acceleration to highway speed.

Typically, though, the higher performance engines were set up with colder plugs than the normal engines were to allow for longer periods of WOT application without the plugs going into "melt down" or detonation from the plug not dissipating enough heat too enough. In many cases, they were driven normally rather than to see lots of low-speed use.

Starting with what the factory spec plug was, at least to get the engine running and enjoyed some, might be a good plan.

Enjoy!

NTX5467