Same as 4.6 but with .060 over pistons (3.935" bore). Adds ~70cc of displacement, marginal HP gain, slightly weaker cylinder walls.
The 4.7 stroker is the 4.6 build taken one bore size further — .060" over instead of .030". Final displacement is 4657cc (284ci) versus 4587cc (281ci). The HP/TQ difference between a 4.6 and 4.7 with the same cam/head/intake is small (5-10 hp peak, similar torque). The argument for going 4.7 is that a tired 4.0L block needing more than .030 to clean up is already on the path.
The argument against: cylinder walls at .060 over on the AMC block start getting thin near the deck, and core shift on factory castings can leave one cylinder thinner than the others. Sonic-checking the block before machining is mandatory at .060. Some builders skip the gamble and stay at .030, sourcing a fresh block if needed.
All other components (crank, rods, head, cam, intake, fuel) are identical to the 4.6 build. Pistons are the .060-over version of the same Hesco or KB piston.
Verdict: only go 4.7 if your block sonic-checks clean at .060 or if it already needs that to clean up. Otherwise stay at 4.6.
| Part | Vendor | Est. price |
|---|---|---|
| Hesco short block 4.7 | Hesco | ~$4400 |
| KB pistons +.060 | KB | ~$380 |
Written and maintained by an AZ wheeler and driveway wrencher. Always cross-reference your factory service manual — modifications affect vehicle safety and warranty. Work at your own risk.