msd ditributor and msd ignition and blaster 2 coil

[sua sponte]

I am strippin down my 62 which has a Chevy 350 and I was wondering if the distributor would fit in my 69 which has a 345 in it? And also would I be able to use my msd ignition model#6420 on the 345 as well as the blaster coil 2 model# 8202?

 

[Michael Mayben]

The lower distributor body/drive for any IH I-4/sv engine is unique to that engine series, no other distributor application will work.

The only new distributor series that are available for a IH app are the units from mallory, but those will not include a drive gear, as a suitable donor gear must be sourced and installed.

The davis unified ignition (dui) conversion of a delco hei distributor involves using the top half of an hei unit and marrying it to a custom machined lower drive segment.

Distributor identification information along with pics of a typical mallory unit are in this thread:

http://www.forums.IHPartsAmerica.com/ignition-tech/642-ihc-vehicle-distributor-identification.html

The msd blaster II coil will work with any inductive or cd ignition system as long as it's primary resistance value is a correct match, nothing special about those other than they are a "high turn ratio" item which has a potential kv output of around 35kv as compared to an oem coil potential of a nominal 20kv. The use of an additional ballast resistor sometimes supplied with those coils is totally dependent upon which type of ignition system it's being combined with. And before determining that, you must know what the primary resistance of the coil you have is as measured witha dvom.

The msd 6420 unit is a "six" series capacitive discharge box, known as the "6al" (l stands for included rev limiter which has no use in any IH application). An msd six box can be triggered from points, a magnetic trigger (hei), or pertronix trigger (hall effect). An msd box can use nearly any ignition coil, the primary resistance of the coil is not really important like it is when using a breaker point system. The msd box becomes the ignition system and is "capacitive discharge" design, so the system is noi longer considered "inductive".

 

[sua sponte]

Hey michael when you say to change out the bottom end of the distributor and use the mallory top and my stock 345 bottom end of the distributor is that something that has to be welded or is it something minor that could be done with basic tools?

 

[Michael Mayben]

hey michael when you say to change out the bottom end of the distributor and use the mallory top and my stock 345 bottom end of the distributor is that something that has to be welded or is it something minor that could be done with basic tools?

I May have confused ya here, let me clarify...

The mallory replacement distributor is a drop-in. Available in a dual point version (works great with a msd/mallory box!), unilite version (optical trigger), or mag trigger version (most universal). But you must move a drive gear from a donor distributor to the mallory, then set the endplay, they do not supply a drive gear with a new distributor.

The davis unified ignition (dui) is the bastard of the bunch. Those have an oem delco-type hei upper housing grafted to a custom-machined drive section in the early versions, the later versions are a dedicated one-piece body with a proper IH drive system.

Sometime in late spring/early summer, we will be launching an in-house converted Holley 1500 series distributor under the ihon/CPT brand, those units will be mag trigger so that they can be used stand alone with a carburetor system, available with a mallory or msd "6" box and matching coil for a mega-performance ignition system, and with the cd box, May then be easily converted for use for timing control with efi in the future,...one distributor will do all! These will not use a pertronix conversion, they will be a mag trigger which is far more adaptable in a performance system.