[RKDinOKC]

When I had my 81 GMC Jimmy with a 305 I did an engine swap. Instead of an expensive crate or rebuilt motor, I bought a 78 Monte Carlo from a guy that worked where I did that had a small block 400 for $200. Sold the sans engine Monte Carlo roller with tranny for $200. Did a short block rebuild and 2.02 heads re-machined and rebuilt at a very reputable shop for less than it would have cost me in parts alone. Added RV Cam, High stall, lockup torque converter, Edelbrock aluminum intake, some cheap headers, and chrome valve covers. When swapping in the 400 used a combination of the brackets from both motors to use the newer 81 A/C compressor and strip all the smog stuff. Had the Rochester 4 bbl off the 400 rebuilt and ran it. Then sold the complete 305 engine for $325. I think the whole thing ended up only costing me less than $300 out of pocket.

Ended up going from 12 mpg to 19 mpg with LOTS more power.

An added benefit was 1978 cars were not required to have any smog stuff on em but 1981 did. Just had to go to an inspection station and pay $5 for a guy to read the serial number off the motor for a smog exemption certificate..