going over the numbers on base plates for 440-6's.......can someone tell me what mine is for? The number on the base plate is # 2946386-made in Canada.Looking through other materials....I have found other numbers but not these.I realize a 70 and 71 base plate are different for the airgrabber. I always assumed that this was an original on my 70RR....but now I'm not so sure. Any help will be greatly appreciated. Thanks

Can't find a 2946386 in my 70 parts book. 2946389 is the 440-6 baseplate for 70 and 71 with fresh air option. Do you have a picture? Mis-stamp? Here's my NOS 2946389...

From what I've dug up is that #3512765 is used for 1970 and #2946389 for 1971.As for mine....#2946386 you can see why I'm confused. Attached are the photos of the baseplate

And.......

and ....what exactly is the difference between the 2 years......

Probably a summer student hired at Fram came in for work one morning hung over and when spinning the Trodat 'Made in Canada' stamp to correct 2946389 number for that days' assignment of stamping the bases, let it stop at at a 6 instead of a 9.....thats all.
Hopefully yours is the only one he did that way before waking up.
Same kid likely did this one too, all backward numbered on a 340 shaker base

I'll go along with that explanation...that must make it rare than! lol I wish!! The cars are built by humans. Do you know what the difference between the 2 years in baseplates. Apparently I've had that 71 baseplate on my car since 1981 and it seems to seal good on my 70 and no one has ever noticed. Looking through books and magazines....I cant tell the difference.

Oh those crazy Canuks.

So......nobody knows what the difference between a 70 and 71 sixpack baseplate for an airgrabber is or why they have different part numbers????

There is no difference in the 440-6 air grabber base for 70 and 71.
They use the same part number 2946389 and are identical.
I dont know what source you got the info from regarding part number 3512765 but 3512765 is a 1970 340 4 barrel shaker base.

I'm losing faith in "Charger,roadrunner & super bee restoration guide" by Paul Herd. It was stated on page 43 //// just a suggestion....Moparts should put out their collaberated restoration guide!---Number one seller...

You Herd it right here...that book is chocked full of errors