Hi all im new and ive not been able to find anyone that knows were i should place my new bb motor mounts im new at this stuff but my old motor mounts were for a small block but i know they work for a big block as well but i decided to go with energy suspension.So do i, since i am swapping my 350 out for my 502zz will the same spots were the old motor mounts work for my new ones?I wasnt sure were to weld them in at,since they dont bolt up to the stock sub frame holes.and wil welding be good enough? thanks for reading my question..Ill buy a beer for any one who can help lol...or a six pack..ty ron my email is rizzon0001@hotmail.com

 

why aren't they lining up to your old holes? they totally should

 

well im sure why ive gotten 2 kinds and neither ones had the holes lined up so i asume they never had a 72 bigblock mounts i mean i could of gotten new stock ones they would of lined up ...

 

that dont make no sence why they arent lining up

 

they should bolt right in. I have the same ones in my 70 and it has a bb. fit with no problem. And 70-73 had the same subframe bolt holes in them. A little more info or pics would help us understand better.

 

well the old mounts were the old style were the pad goes on the subframe these new ones have the pads on the motor..

 

I am thinking that soemthing is up with the mounts bc i put in my car a 454 that was older and it bolted right up to the new mounts.

 

did you upgrade to newer style poly mounts?Were the pad goes onto the motor istead of the originals that the pad goes on the frame..Those bolt right up but the vibration is to much so i really wanted to upgrade.Oh another question is will the bigblock mount to the exact same holes as the small block mounts?Or is there a need of adjustment for the bigger motor?Im a nub at all this......ty for your help...

 

It should bolt right in,I swapped out a 327 for a 427 in a '69 and only needed the right mounts on the engine and it dropped right in.
The only issue was the heater core had to be changed to the special BB core because the hose connection on the stock SB core end up behind the head.
I think this is only an issue with '67-'69 cars though.

 

yes you will need to fill the heatercore holes in the firewall and drill new holes in the heaterbox and it's nice to fab some brackets on the inside to hold it from flopping around. some people keep the old lines in place but it is bad to do that.

the only other possible clearance problem you can have is tall valve covers with powerbrakes if you have a normal sized booster