I'd agree with Pete, and it seems over the years my old car and modified specials friends would say the same too. I just wish NGK did a RSN13-P replacement. . . . . . . . . .!

The Ford hot-start hassles we can't blame entirely (in the UK anyway) on the old flat-head although they were never good at it; the EU-law specified high volatility fuel does not help and set to get worse as they are about to jack up the RVP again in a further low-pollution effort. Let's just hope they don't get the US alcohol (MTBE) idea - all very well in a continuously computer tweaked, closed-loop injection system but likely a re-jet hassle in an old carb. (and has just happened to a US friend with carburated UK MVs)

Ballard's F15 seems to favour the technique defined on a windscreen sticker found in the last carburated Ford cars here, half throttle and crank, keeping the revs well up when it fires and steadily backing the throttle over several seconds for a fast idle as the engine clears itself and settles.

I re-fitted his truck with really meaty, 1" dia core, starter cables of self-manufacture and kept the length to a minimum, not forgetting you not only have to get huge amps into the starter on a 6V system but get them back to the battery too, so similarly huge chassis/engine bond and continued back from there to the battery.

The starter is lucky to even see 4V when cranking on these old 6V systems and hence the trick 8V batteries we hear of from down under. Its never failed yet but you do have to whirr it around for several seconds after a run on a really hot day and there's always that moment of anxiety.

R.