IHC Vehicle Distributor Identification

[Michael Mayben]

I overlooked your response regarding the list on the Holley carb you are using.

That is a 2210c based upon the list 7309 in the pic.

That carb is discussed in detail in this thread, starting with post #22:

http://www.forums.IHPartsAmerica.com/carb-tech/511-Holley-22xx-series-carb-stuff.html

The 22xx series carbs were never available with a governor system, those were/are throwaway emissions carbs.

So the engine system you have is not a "governed" engine, it's the same power unit that was installed as standard stuff in light duty Scout II, pickups, and travelalls of the same era. There were variations in the engine support systems used in the various platforms though. Some blocks were/are machined and drilled for all variations, some are not.

 

[Bill Bennett]

Mike, check your e-mail box. I sent you the dist specs.
Bill bennett

 

[Michael Mayben]

As long as ihc-variation distributors keep popping up, I'll keep posting.

Here's yet another variation of a mallory aftermarket replacement distributor for the sv engine application. The "unilite" 37 series. This model has mechanical advance only, it's companion is the "47 series" which mounts a vacuum advance unit.

mallory :: product details

The unilite distributors have been around for years, one of the very first performance "breakerless" distributor designs. These units use a photo-optic trigger system and must be used with the rotor assembly shown...aka "shutter wheel" by some.

Mallory uses the same basic distributor body and drive system for all ihc engine apps of their distributors, just changing the type of trigger system used internally.

This item belongs to mikee roth and came to him in a recent purchase of a lot of sii race truck parts. However, this unit was never set up properly and has an exorbitant amount of end play present since someone did not shim the drive gear correctly. It will be disassembled and inspected for damage and repaired if needed, then the drive gear will be properly installed.

Over the years, the unilite series has gained a rep in some circles for being unreliable. But if that was a fact, then they would not have remained in production and have sold in the 10's of thousands of units over the years. I have no doubt that the reputation is impacted by incorrect installation. These units must have a proper spec ballast resistor installed, dependent on which ignition coil it's paired with. If used to trigger a add-on cd box, then a ballast May or May not be required:

http://www.malloryperformance.com/pdf/1214m.pdf

 

[towpainter3]

Distributor id question. Michael, I have what appears to be a prestolite electronic dizzy. It has 3 wires coming from the side and the vac canister. Under the rotor button is an electronic board with the motorola logos on the diodes and such. There are no part numbers that I can find. Any info will be helpful I will get a pic on here in a few. Thanks brad

 

[Michael Mayben]

Regarding the prestolite electronic distributor...the electronic module is under the breaker plate component to which the pickup assembly attaches. Don't know about any electronics that might be mounted under the rotor button????

Pics will tell the story though.

 

[towpainter3]

Michael, sorry bout the misleading info,the module is under the breaker plate and the little white colored pickup is the only thing mounted on the plate. They have installed the wrong cap , according to the previous threads, female lugs should be male? Correct? Will post pics in the next reply if I can figure it out . This damn lectronic thang aint no junk iron.

 

[ronmc1954]

Brad, here's a pic of the prestolite I just installed in my rig, it's just the top view but it sure sound like the one you have.

Ron

 

[Michael Mayben]

michael, sorry bout the misleading info,the module is under the breaker plate and the little white colored pickup is the only thing mounted on the plate. They have installed the wrong cap , according to the previous threads, female lugs should be male? Correct? Will post pics in the next reply if I can figure it out . This damn lectronic thang aint no junk iron.

No doubt what you have is the prestolite electronic as shown in ron's pic.

There are several things "wrong" with trying to interchange the caps between the Holley and the prestolite-pattern distributor bodies. Primarily...they don't fit correctly! And to really add to mystery performance, the phasing of the terminals in the two caps is not the same resulting in really crappy performance.

There is a way to use the prestolite cap on a Holley body, I did a swap on Jeff's converted efi Holley distributor on his white sii yesterday...but even that one is not optimum...yet.

Yes...a correct cap for the prestolite will have male terminals (contrary to popular belief, delco did not originate that concept as seen in an hei distributor design). Also..stay away from the aftermarket prestolite caps with aluminum terminals/contactors...those are garbage...and the internal terminals are not shaped/manufactured correctly for the prestolite rotor design.

I'll post some additional info with pics regarding the prestolite sparker this coming week after I get home and can shoot some pics of the sample parts.

The time we spent with navybill and navyjoe this past week dealing with the efi-enabled distributor variations will result in a converted distributor that is optimized with all the good stuff that fits properly and can be used with or without efi.

 

[towpainter3]

Yep thats the puppy. Ok now can this diz be hooked up like a GM hei to eliminate the points diz I have now and if so how. I can purchase the correct cap and rotor thru napa only one I can seem to find at the wally world stores are the junky aluminum contact ones. Good thing there are still a few good part stores around. Anyway I woulld love to do the swap if possible. If not oh well. Any info would be greatly appreciated. Thanks.

 

[ronmc1954]

I guess it depends on if the dizzy is for IH or not. If you read my post mm discribes the install.
http://www.forums.IHPartsAmerica.com/ignition-tech/2900-prestolite-dizzy-question.html

One thing I found out is that the dust cover is an important part, it acually fits over the rim of the dizzy and makes the cap fit properly.
Good luck, you will definatly notice a difference.
Ron

 

[Michael Mayben]

Thanks to monte and his fil ron, I was able to add to the distributor collection here at binder u. So we can continue updating this thread.

This a prestolite idn-4000 series electronic distributor. These units were phased into light line vehicle production towards the end of the m/y '77 production run. However, they commonly May be found in "retrofit" applications on any I-4, sv, mv, lv engine application, sometimes as a replacement for the Holley 1530 gold box system.

Easily identified due to the use of the male cap terminals, the "square" section design of the body below the cup, and the removable portion of the vacuum advance assembly which retains the calibration spring.

The white wire found in the harness pigtail is used as part of the emissions-related dtm system on some vehicles, and has nothing to do with actual distributor operation. In many applications that wire is simply hanging and not connected to anything.

These are outstanding sparkmakers!

 

[Michael Mayben]

Here the detail of the exterior of the prestolite cap, it's also used for the breaker point prestolite distributor which shares this same body and drive system.

 

[Michael Mayben]

This is the interior of the prestolite cap. A completely differnt design as seen in the Holley caps.

Most significant differences...the flat-type terminals and the way the cap is located on the distributor body itself.

This is an oem-type cap, and also representative of the premium quality caps available for these distributors. Brass terminal that are well bonded to the bakelite receptacles.

The cheezeball caps are going to be found with aluminum terminations and will most likely have several segments that are "loose" in their receptacles and able to move around, that condition sure doesn't provide any stability to ignition timing! But they are much cheeeper than the premium caps, so buyer beware.

 

[Michael Mayben]

Here's the guts.

Ya see the rotor which is somewhat unconventional, we'll look at that next.

Underneath the rotor and attached to the mechanical advance unit is the toothed wheel referred to a the "reluctor" or some May call it the trigger wheel.

The white plastic pod is the actual electronic pickup, it's mounted in an adjustable fashion as part of the setup on these units involves setting the "air gap" between the pickup and the reluictor. The air gap is what determines "dwell", similar to what we understand about a breaker point system. Only in this case, that air gap can't change over time unless the distributor becomes badly worn internally, or some ham-fisted po thinks they can increase performance by tweeking it!

Underneath the "breaker plate" you will find the electronic amplifier/control unit mounted. Again, that is a somewhat unique setup as compared to many other electronic ignition distributors. That module can be replaced as a set along with the breaker plate. There is no other electronic module mounted to the vehicle other than the coil. The bulkhead-mounted dtm module is an emissions device that is controlled to a degree by the distributor amplifier, but has no bearing on distributor functionality.

 

[Michael Mayben]

Here we have the rotor used with this distributor. Again, this item is totally different in design as compared to a Holley rotor. Don't let any parts countermonkey tell ya they are "all the same"!!! No way these rotors will interchange!

Pay close attention to that steel contactor in the center which conducts juice from the coil to the individual plug cable terminations in firing order rotation. Notice the black, rectangular segment between the spring contactor and the flat tip???

Unlike rotors used in most other distributors, this one has a resistor incorporated in it's conductor path! Looks like a tiny battery and is retained just like a battery in a small electronic device also. The idea here is to always have the distributor/coil firing into a load, that enhances coil output same as opening up the spark plug gap or using a now-obsolete "resistor"-type spark plug. It also serves to attenuate electronic "noise" that ya hear through your radio/sound system and can screw with gps nav devices and cell phones.

The problem with these rotors is that they can exhibit significantly increased resistance over time, including going "open" which means no spark to ionize the plug gap, even though there is nothing wrong with the rest of the ignition components! Many new distributors and modules have been sold over time simply because the rotor went open and needed periodic replacement!

I have three of these rotors on hand right now, all appear to be in great shape and are clean and fresh...all are "open"!! After I did surgery on this one, the reason for it's "open" can be easily seen. There is considerable corrosion between the ends of the resistor element and the conductors at each end. Just like we see with dry cell batteries inside of battery holders that have corroded!

The upper limit for resistance of these rotors is 6,000ohms per the service manual.

The Scout II (and many other service manuals have complete service information for these distributors, along with identification information based upon the IH part number and the prestolite series number stamped on the tag attached to the main body.

 

[ronmc1954]

Alright michael I have to ask

thanks to monte and his fil ron,

What the hell is fil, the only thing I can find is that it refers to my "fuctional impairment level"

I think my fuctional impairment level is as good as anybody elses at binder u

I just can't spell as good as u guys

lol
ron

 

[Michael Dimock]

hahaha fil stands for father in law.

 

[Michael Mayben]

hahaha fil stands for father in law.

Yep! At least mikee has retained summa that crap they filled him with in post-secondary escapade!

But hopefully he won't end up with a fil when goes south for the winter, or even worse a mil! He needs to stay focused on the training he's gonna receive from Darren in azzkickin', crapper douchin', and maybe if he's fortunate...weld grindin'.

Go out and break the I.c.e. Off the hood and check that rotor ron!

 

[ronmc1954]

Break the ice you say, it's supposed to get down to -37f tonight and that's air temp no wind chill
brrrrr

 

[towpainter3]

After searching the napa website I found a cap and rotor for the 4000 series dizzy at a etter price than a/z or adv/ or orielly. The picture shows the cap to have brass male studs and the rotor appears exactly as in the previous pics on here. The p/n are as follows
cap mpe al162sb $7.69
rotor mpe al163sb $6.29

these appear to be as the site says a high quality yet economical oem replacement. They damn sure beat the other guys aluminum studded caps and chinese rotor. According to the guy at napa they are manufactured in the usa by echlin.
Whats your 2 cents on this m/m