ID on motor mounts?

[matt030305]

I have these motor mounts that came off of of 1971 duster (originally a /6)with a 340. I was wondering if these mounts are standard mounts (if so, which side is which) or the conversion mounts (I6-V8 mounts)

 

[crackedback]

Right one is a std 318 driver side bracket.

If the ear sizing/spacing for the bolt holes to biscuit surface are the same on each. Looks like a pair of 273-318 brackets. Not 340's or 360 mounts.

 

[matt030305]

Okay cool, I’m putting a 408 Stroker in my car. Should I upgrade these brackets to std 340/360 ones?

 

[doug 371]

standard

 

[crackedback]

Okay cool, I’m putting a 408 Stroker in my car. Should I upgrade these brackets to std 340/360 ones?

A 340 drivers mount is more narrow than the pass side. That mount is also missing the ear for the mount hole to ear location on a 340.

The bottom one is the bracket you have... Top is a 340 bracket

If you can weld, it's an easy fab to make the bracket you have work. I have done a bunch of them over the years.

 

[Professor Fate]

I have these motor mounts that came off of of 1971 duster (originally a /6)with a 340. I was wondering if these mounts are standard mounts (if so, which side is which) or the conversion mounts (I6-V8 mounts)
View attachment 1716369070

I can't tell from your picture, the one on the left is unidentifiable as you have it angled in the picture.
It could be either of these:
A smallblock P. side truck bracket, commonly used to adapt a smallblock to the '67-'72 slant 6 K frame; and basically the same as the popular brands of conversion mounts (Schumacher, Trans-Dapt, etc.):

Or it could be the standard A body P. side bracket:

A picture of yours fron the side or at least more of an angle would help a lot.

 

[matt030305]

Will do, I’ll just buy a new set of mounts from Mancini. Thanks.