[Healeys] Backfire

[Bob Spidell]

Symptoms suggest fuel delivery (faulty pump, clogged filter, etc.).

What cap and wires are you running? If stranded wire secondaries they 
could be affecting the Pertronix from RFI (the guys on Roadkill Garage 
had that issue with an old Chevy dragster). The larger the plug gap the 
more voltage produced at the plug electrodes (IMO 0.035 is pushing it 
and not really necessary).

Bob

On 9/19/2025 2:36 PM, Richard Antal via Healeys wrote:
> Gents,
>      A few days ago I replaced the sparkplugs, ten years old or more, 
> with six NGK BP5ES plugs gapped to 35, and a Pertronix 3 ohm coil. 
> I've not yet changed the wires, distributor cap or rotor. Today I 
> drove the BJ8 almost 200 miles without incident at speeds up to 60 
> mph. While going 80 mph on the interstate, over a span of two or three 
> seconds, the car bucked and backfired three times. I immediately 
> dropped the speed to 50 and then gradually back up to 80 with no 
> further backfiring. What could have caused this discomfiting turn of 
> events? Thanks for your thoughts.
> rich antal
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