Hmmm.... my document (1973-74 parts catalog) says the only 4980 series engines used prior to 1974 are the 498058 and 498059, both applicable to the '73 model year only. The 498048 is shown as used in 142/144/145 models in 1974. If that's the case, more likely it's an 8 bolt.

I'd never looked into this before, but if it turns out this (4980 series) engine *is* an 8 bolt, you have to wonder - are all 4980's 8 bolt engines, while the other 49XX series (e.g. 4969, 4982) are 6 bolt? Has anyone ever attempted that correlation? Sure looks like a good possibility from here; the 1974 model year 140's were apparently shipped with nothing but 4980's, with a very light sprinkling of same showing up in the 1973 model year. One could guess those (1973) 4980's may have been late production. The remainder (and vast majority) of 1973 engines shipped in 140 series cars appears to have been 4982 series.
--

Gary L - 142E ITB race car, 73 1800ES
BlueBrick Racing Website
YouTube Racing Videos