I just pulled my 5.0 from my 1989 150 and was in the procces of installing a4.9 out of a 1991 two wheel drive but the motor mounts do not line up w/the mounts on the frame. any ideas?

 

The mounts and frame perches are different. You need them from the 4.9 truck. Or you need a 5.0 or 5.8 which will bolt right up.

 

The V8s are 4 cylinders long, so the mounts are roughly centered on the block between the 2nd & 3rd cylinders; the I6 mounts are between the 3rd & 4th, so they're farther forward from the firewall.

Why are you putting in a different engine? It might be easier to put the good '89 parts into the '91 chassis. The truck would be worth slightly more, being 2 years newer.

The 4.9L frame perches are bolted on top of the crossmember; the smallblock V8 perches are bolted & riveted to the back of the crossmember.


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But there are several other differences, including the radiator, Y-pipe, & fuel lines.

 

In case you are interested, I did a 351 swap to replace my tired old 300 six. I still have the 300's perches if you need them...