'84-'85 GN Maf = Cardone #74-7699
'86-'87 GN Maf = Cardone #74-7899

Any ideas on the differences?

 

yes 84-85 is a hot wire Bosch tpi design i do belive and the 86-87 peice is a film style AC delco peice. it could be the other way around.

 

My sources are quoted as having said -

'The hot-film MAFs, which AC Rochester
introduced in 1984 on the Buick turbo 3.8L
V6 and were also used on Chevrolet 2.8L
engines and GM 3.0L and 3.8L V6 engines,
produce a square-wave variable frequency
output. The frequency range varies from 32
to 150 Hz, with 32 Hz being average for idle
and 150 Hz for wide-open throttle'

This from a Wells Counterpoint issue.

Perhaps the '84-'85 are the hot film frequency based MAFs, similar to the 2.8's?

 

I believe you are correct in the frequency output of the earlier ones. Cant verify the use of them on toher cars however.

I dont know alot about the earlier ones, but the later 86-89 MAF was pretty much junk if u got a good one , u did, the rest would just crap out in a week it seems. Something like a MAF translator(if u can make it work) may work really nice for you if u can use it. Let u run a late model MAF and they are alot cheaper and way more reliable.

later
Jeremy

 

Hmm... I think I'll pick up like an '84 GN Maf, see about using it in place of the stock 2.8 one