Hi Guys - I am in the process of swapping out the original Motorcraft Distributor in my 351w (now 408) to a Petronix distributor Part# D7131810. When they are side by side the original motorcraft distributor is approx 5/8th" longer than the Petronix unit. The Petronix unit seems to fit fine and seats nice but my concern is having that 5/8th less shaft on the oil pump. There seems to be plenty of engagement on both units but I'd hate to have a failure at that point. I have a call out to Petronix tech support but so far have not heard anything. Thoughts/ideas? or am I just being paranoid...
Can’t give you a definitive answer on the length and pump shaft engagement, I have what’s probably the same one on a 302 (not sure if the 351 is taller?). Suggestion I took from others, make sure you swap the oil pump shaft for a stronger hardened one if you are running something stock.
My other piece of advice is don’t leave the ignition on with the engine not running for more than 30 seconds with the pertronix. I had my ingnitor module burn out and search on the internet tells me it is caused by leaving the ignition on. Pertronix replaced it under warranty so they do stand behind their product.