is it safe to run nitrous on flathead pistons? with a CR of about 9:1

depends...are the pistons forged? Cast pistons migh not survive very long

Agreed.... the pistons better be forged or you will see pieces on your piston lands coming out the tailpipe (if you're lucky).



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"Freedom of speech makes it much easier to spot the idiots."

Not an expert, but I was under the understanding that flattops were fine, even preferred for nitrous over dished and domed. You can run squeeze on cast pistons, but do not EVER, EVER run lean. If going over 125 shot (175 for BB) then you want to REALLY think about going forged.