The factory options were:
* 2.8L V6: This is the smallest engine offered.
* 3.1L V6: A slightly larger V6 option.
* 5.0L V8 (TPI): A popular choice.
* 5.7L V8 (TPI): A larger V8 option.
You *could* fit significantly larger engines, but this would require extensive modifications, potentially including:
* New engine mounts: Larger engines will not fit the existing mounts. Custom fabrication will be needed.
* Modified firewall: A larger engine might require cutting and modification of the firewall.
* Exhaust system modifications: The exhaust system will need to be completely reworked.
* Transmission and drivetrain modifications: You might need a stronger transmission and possibly a different rear-end to handle the increased power.
* Cooling system upgrades: Larger engines generate more heat and will require a more robust cooling system.
Essentially, while you can fit bigger engines, the cost and complexity increase dramatically. Swapping in a slightly larger V8 (like a 6.0L LS-series engine, a popular swap) is relatively common and manageable with the right skills and parts. Going much larger than that quickly becomes a major undertaking.
In short, there's no single answer. It depends on your budget, mechanical skills, and the level of modification you're willing to undertake.
