I'm happy with the coil strengths on my Seawitch. The lower flipper coils are AQ-25-500/34-4500 and I obtained them from Pinball Resource. The uppers are J-25-600/34-4500; they are red Stern coils & may be the originals. If you go too strong on the top coils you may end up replacing broken drop targets on the center bank from shots off the upper left flipper. I've replaced one so far.

And many of the games came with a 5W resistor attached to the upper coils to weaken them so the nearby DTs would not be destroyed. Don't go bigger. If you do, you could always increase the gap in the leaf switch contact points to reduce power.

I believe that's a 1 ohm resistor, btw.

I just played a couple dozen games of Seawitch & I don't think that I would want the upper flippers to be any stronger. BTW: there are resistors on my upper left flipper but not on the upper right.

For the OP, are you sure you are looking at a Seawitch manual? I haven't seen 450 flipper coils specified in any classic Stern except for Galaxy. 475 coil should be your coil of choice on both the lower left and right flipper per the Seawitch manual and 1981 Stern parts catalog. You do NOT want to go any stronger than the 600 on those upper coils, really no need.

First off, what triggers this question to begin with? Are yours sluggish? Have you rebuilt first? Have you compared rebuilt flippers to those in youtube vids of seawitch? Or do you just want to make them more powerful for some reason?

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