msd distrubitor question

[GerryP]

Don't be a slave to MSD.  You can use any OEM or aftermarket module.  Yes, even a Ford Duraspark box.  Or an HEI.  Accel makes a very nice HEI module that is as good as the factory originals in that it increases coil dwell with RPM.  All the module does in to interpret the pickup signal and then interrupt the coil's field current, which causes the spark.  By using a non capacitive box, like the MSD, you are just back to the standard inductive ignition.

[fryedaddy]

can someone give me a part number for a good module that will work with my pro billit distributor

[GerryP]

These HEI modules will work:  D1906, DM1906, LX301, TP45.  You would also need the heat sink for the module:  https://www.amazon.com/Genuine-Parts-19351887-Airflow-Sensor/dp/B0012P2EQU/ref=d_pd_day0_vft_none_sccl_3_5/144-8759243-6838835?pd_rd_w=vXU2s&content-id=amzn1.sym.8ca997d7-1ea0-4c8f-9e14-a6d756b83e30&pf_rd_p=8ca997d7-1ea0-4c8f-9e14-a6d756b83e30&pf_rd_r=ZJ7QZ16XE4X9ADMKVQZK&pd_rd_wg=6Dny7&pd_rd_r=40f8be70-d9bc-4f1e-9d16-ad7e0f026847&pd_rd_i=B0012P2EQU&psc=1  You also need the heat sink grease to make sure the module transfers that heat to the sink: https://www.amazon.com/StarTech-com-Thermal-Grease-Compound-Heatsinks/dp/B005VULWLA/ref=sr_1_1_sspa?keywords=heat+sink+grease&qid=1686596608&sr=8-1-spons&psc=1&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUExWjRCM0pKR1dBRE9JJmVuY3J5cHRlZElkPUEwNDEwMjIxMjNSNVdETjZDVzdXMSZlbmNyeXB0ZWRBZElkPUEwMTUyNTQzMzcxU0owM0YwOFpJTCZ3aWRnZXROYW1lPXNwX2F0ZiZhY3Rpb249Y2xpY2tSZWRpcmVjdCZkb05vdExvZ0NsaWNrPXRydWU=

There may be adapters out there for any number of modules, but you'll have to search.  And you can always splice in whatever connector you want.  I made my own connector for a Duraspark distributor to an MSD box.

[fryedaddy]

thanks for the part numbers,as cheap as these modules are you would think that it would make the several hundred dollar boxes be hard to sell.

[fryedaddy]

i bought the accel module.i will have to do some research on how to wire it up,not sure if you use both wires coming off the distributor.

[GerryP]

You do use both wires:  https://www.camaros.net/threads/remote-mount-hei-module.462339/

Also, the NAPA TP45 module is the same performance wise as the very best high performance GM 990 module.  About the same price as the Accel module.

[fryedaddy]

im going to try the accel module,but my son found a bad diode in the msd box,he said it burned up first so the rest of the  box would not be damaged and it would also be a easy fix when repairing..

[fryedaddy]

rewired my ignition with the accel module,fired up instantly.i left my harness for the box in the car,if my son gets the box fixed,i will have a backup.

[GerryP]

...if my son gets the box fixed,i will have a backup.

It is more practical to get spare 4-pin HEI modules since you can carry those as spares in the glove box along with a spare pickup.  Just like the old days of carrying a spare set of points and condenser.  You got the heat sink and the grease too?

[fryedaddy]

my son made me a custom heat sink,it even has a small computer fan on it,and he had some military grade paste to put on it.its overkill but thats ok.you are right,i have a extra coil new in the box,new pickup,all i need is another 4 pin module and i will be set with about everything i need in case of failure.it may be me but my engine seems more responsive with the new module vs the box.it even idles without a choke in just a few seconds from starting.

[GerryP]

The difference is that instead of a capacitive ignition, you are back to using an inductive ignition, which is what the factories have been using for more than 100 years.  An inductive ignition has a longer duration spark, which is better for a good burn, and since electricity is passive, it has just as much energy as a CD in most cases.  CD is great when you have a hard to light burn but offer no advantage over inductive ignition in most nearly all street applications.

[fryedaddy]

no doubt,its more responsive and it is no longer cold natured,you do not have to play with the throttle to keep it running when you first start it.it idles right away.im liking that

[fryedaddy]

WILL CHANGING FROM A MSD BOX TO A GM MODULE EFFECT MY TIMING,DOES IT NEED TO BE CHECKED OR RESET?

[GerryP]

A four pin HEI module does not retard timing.  If you get a five pin module, the fifth pin, when grounded, will retard the timing by five degrees.  The module does this in concert with a knock sensor and timing control.  It's a nice feature for when you might be in a situation, like a race car, where your timing is optimized for the run but is too far advanced for starting.

[fryedaddy]

The reason i asked about the timing is im getting a backfire and i dont know why.would the initial timing be different