just slightly to get a bigger spark.cruiserbrett said:I would go with plugs for the ignition. compression ratio and other factors are similar for both motors, ignition is certainly stronger with the FJ60 dist/coil. Maybe the FJ60 plugs take advantage of the ignition better???
I think my 76 2F took BPR5ES NGK plugs. what's the FJ60 take?
Yep. They started at .060" when GM first brought out the system. I'm not sure what a new car spec is or whether it's been changed over the years but if you've got one I'd say that trying out .050" won't hurt and might amaze you.brian said:so then how big a gap should a 2f with an HEI setup have?
more than .035?
Could be - as I said, I don't know how far they've brought it. But the gap ought to be in line with the spec for the system. It goes to how much voltage is used. I mean if it's a '75 HEI and that year used .060" then so should the current user. If as you say newer systems are using .10" and your system is one of those newer ones then .10" would be your gap.brian said:i would say it's larger, almost twice as large.
i'llll, have to let my Friend know this, so He can properly gap HIS plugs........
Performance and economy gains for high voltage ignitions are one of those things that sounds good, but in practice it doesn't really accomplish anything.honk said:Large gap produces a hot long duration arc fully igniting the fuel charge and producing a potential for better performance in both total output and fuel economy.
LOL! No, but if I had I'd probably have been paid better than I was at the time. I think that GM came out with the system as part of their attempts to meet the then new and for the manufacturers very difficult to meet federal emmissions standards. As such it's one of the better ideas - far better than the screwed up carburation, the injection of raw air behind exhaust ports, and the myriad heaters, coolers, fans, and other attempts to clean up tailpipes without having the expense of major retooling and innovative engineering.Rocky_LC said:Quote:
I think Honk used to write marketing brocuures for GM.
That said - I agree with him (and everyone else). Pick the plugs for the motor and gap for the ignition.