I pulled my old 1994 Rockhopper FS out of the shed and cleaning it up. I am looking at upgrading the front suspension shock from the OE to a vintage Rockshox. Does anyone know the specific levels of worst to best in the vintage Rockshox? Been looking at a few Judy's but I don't know where they fall in their product line.

what size is the steerer tube/head set? threaded? threadless?

judy's....there's a couple different levels within that group, as i recall. all pretty much mid range.

you might consider manitou or marzocchi in your options, too. i have a couple of mid 90 era marz' forks and they beat the two rock shox i have. not like the rock shox suck. they're just the bushing/spring type

1 1/8; Threadless.

I'll take a look at those as well. The current shock is way soft, and just wanting something a bit firm. But then again, it's going to be more of a gravel flat trail bike, not jumping rocks!

Cool! I have a '97 Rockhopper A1 FS that I recently dug out of the basement of my parents' house. I'm going to get a shorter stem and riser bars to make it more comfy to ride.

Looks like your '94 RH FS came with a SR DuoTrack 8001 suspension (source here)

My '97 RH A1 FS has the original Rock Shox Indy C it came with and I like it. (stats here) If I remember correctly the Indy C is below (cheaper) than the Judy.

I found a website retroforksbike.pl that might have the info you're looking for.

Sure you don't just want to go rigid? I have a 98 Stumpy and the Judy XC is pretty meh like all 90s suspension forks, I would rather it was rigid like my 92 Cinder Cone.. To get a really worthwhile upgrade you have to look at finding a susp fork from 2001+ IMO and keep the travel <=80mm,, no easy task.. Rigid would cut a few pounds and then you can invest in some nice new tires.

in that case, the bushing/spring rock shox work well for that, imo. i have an indy xc and another one...don't remember the model offhand. i'll check that later and post. those two would give you something to look for on the bay.
yeah, there are much better forks these days. and, better forks even say ten years newer than your bike. but, as you probably know, the axle to crown height and fork travel will be your limiting factor on choices.
trawl ebay for forks. otoh, there's a website that sells refurb'ed marzocchi forks. i can try to find it for you at another point, but the guy's name is marzocchi mike....or something like that. get an older bomber Z1 or Z2. fully adjustable, linear pull brake compatible (or for some extra, a hanger and you can use canti's). just make sure the travel is around 70 or 80mm's and no more.

edit: i think this is the site i was thinking of...... https://www.mtbforksbymark.com/forks-4-sale. i'll have to check my old emails and make sure that's it. otherwise, this link is at least one more place for forks

How is your '94 threadless? I have a '93 and a '95 and they're both 1 1/8 threaded.

Not sure how/or why, but it's threadless. Bought it new, and bike is completely stock.

Thanks. Stock, as it is now, is prob ok for what I am going to do (I am mostly a roadie) flat trails here in coastal SC. I was just thinking it might be nice to get something a little firmer...definitely going used, and prob not much more than $150, and would really like to keep it within the year range as well. Don't really need anything with newer technology. I am looking at upgrading the group to XTR (again same vintage) and going to at 175 crank.