QUOTE(Dave_Darling @ Feb 21 2018, 10:51 AM)
The original size for a 76 would be 165/80-15. There are a few cheap tires you can get in that size; I suggest using one of those as a spare would be fine.
Caveat: If you have tires that differ significantly in overall diameter from the 165/80s, you may need to look for a lower aspect ratio number (e.g., 165/70) so the overall diameter is close.
If you're worried about the lug bolts--and you might be right to be worried--then pick up a set of four of the short steel-wheel lug bolts. Keep 'em with the spare.
--DD
Morrie,
You also may be able to fins a decent 4-lug Fuchs 2L wheel FS on here, evil-bay, etc. for not too bad of a price to use as your spare. I've seen some single & 2 odd wheels listed lately.
Dave & Mark are correct - if you use the steel spare, then you'll need to also carry a set of the shorter lug bolts for the steel wheels. AFAIK they're stil available from Porsche (try Sunset Porsche OR or Suncoast Porsche FL for best price on Classic parts), as well as repro bolts around, but you'll need the proper acorn head - not conical.
I think Firestone/Bridgestone sells an affordable 165/80TR15 tire (HR was on 2.0's, but T speed rating is adequate, or even an SR for a spare), or else go with the Vredestein 165HR15 (/80) as a good all around street tire in the original size, which won't break the bank.
Just google for the 165/80R15 tires, then go from there.
PS - The 185/75R15 & 185/70R15 tires should also fit in the spare tire well, since they were commonly used back in the day, & a factory option - so I doubt that an 165/80R15 could be that much bigger. If your current spare is a 195/80R15 or something, then it may not fit, but then it may not fit in use on your 914 too without rubbing somehwere (unless your fenders are rolled, puller or flared).
Tom
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