[adynes]

A little off topic, but was wondering what you guys know about the 7 pin components.

I retrofitted a 7 pin module into a 4 pin distributor for timing control with megasquirt. Seems to work fine so far.

Looking at pictures on rockauto, the pickup coil in 7 pin distributors have an extra plate on top. Also, there is a thin sheetmetal piece covering the module. Are these for shielding? Are there any other significant differences in the 7 pin components?

Rockauto lists the same ignition coils for both distributor types, but they have two options of the 'white wire' coils. D505a and D555a. What it's the difference in these two coils? Is one better for use with a 7 pin module?
Edit: looks like the D555a is a little longer (more windings?)

[Sun Tuned]

Well it seems there's not a whole lot that will even be noticed on this deal.

These modules are running in the $2.37 range per unit cost to the larger parts houses...

Doubt anyone will even bat an eye here. They can give you 5 before even needing to remotely worry about the thing at all. Most will give up after that many.

[Schurkey]

Originally Posted by adynes

ARockauto lists the same ignition coils for both distributor types, but they have two options of the 'white wire' coils. D505a and D555a. What it's the difference in these two coils? Is one better for use with a 7 pin module?
Edit: looks like the D555a is a little longer (more windings?)

D505A is listed as "Original Equipment" "undergoes more stringent testing than aftermarket products."
D555A is listed as "Professional, premium aftermarket replacement "

I have a dollar that says they're the same part from the same factory, with different part numbers, and different warranty. But what do I know?

[SRR]

I work in a parts store and it has a module tester. I have tested modules that tested good even after being tested 5-6 times and when put back in the car-have running issues. The only thing I could think of when tightened down, this would cause the issues. Parts quality control as mentioned has gone to crap. For example: Bought pilot bushing for SBC, was very hard to install, fit on trans shaft before install but not after install. Took hell to get it out. Bought another thinking I wart hogged it. Measured this one and it was 6 thousands larger than the hole in the crank??? Had to turn it down in a lathe to make it fit. One more, needed a starter for my 1994 6.5 Diesel C3500, saw one on amazon for $40. less than parts store and in the comments were several saying the mounting holes weren't drilled correctly. Screw that. One more! Fuel module needed to be replaced on same truck, bought it and the mounting relocation kit from Summit. Module was USA made! Relocation "kit" made in China, the allen screws were not made good at all, no Allen metric or SAE would fit...The threads in the mounting plate must have been tapped with a dull tap as the screws went in very hard. I was happy to see the module came with properly made screw. Oh, the lock for the connector snapped off when I plugged in. I just tie wrapped it.