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can anyone tell my looking at this engine which one it is.. the ad says 4.1 but they didnt put that trash in the rivs.. so is this a 350 in this 81 riv on ebay?

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1&item=4532868279&category=6142

can anyone tell my looking at this engine which one it is.. the ad says 4.1 but they didnt put that trash in the rivs.. so is this a 350 in this 81 riv on ebay?

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1&item=4532868279&category=6142

Yes , sorry to say it is a 4.1/252 CI
In the 81 Riviera, it had 4 different motor's to chose from.
3.8/231 w/turbo
4.1/252
5.0/307
5.7/350