19mm Gudgeon pin rods and standard pistons

ibiza_95

1.8T MK2 Conversion
I have a set of forged rods, with the 19mm wrist pins, and a set of standard pistons to suit.

While i got these at a decent price im left wondering whether i should have waited and got some of the 20mm pinned rods. The pistons are standard units and came attached to the rods.

Can anyone tell me what the pistons will be good to see power wise and whether the 19mm pinned rods are weaker than the 20mm ones? if so by how much? and im not being petty am i with the pin size?

I know the weakest point of the engine is the rods hence me opting for the forged items, I only want to be building the engine once more now, 3 times is enough for me, but depending what power standard pistons can take and the difference in wrist pins will either mean i hold out for some stronger pistons, put them in as they are, or sell the 19mm pinned rods and buy a set of 20mm rods and stronger pistons.

Thanks for any info and advice.

EDIT: This is all on a 1.8T engine running k04 RR'd at 258bhp with nitrous ontop of that
 
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