What is the biggest engine I can fit in a 1997 Pontiac firebird
I think the largest motor from the factory was the 5.7L but im sure you can go bigger with some modifaction.
You can shoe horn what ever you want in there just takes time and costs money. Michael is right the largest factory engine is the 5.7L LT1. They were also a limited amount with the WS6 Ram air with 20 more HP. And the Firehawks had the Corvette LT4. Base engine is the 3.8. If you have the 3.8 you'll need to swap PCM and wiring harness to use the 350. Intake, exhaust, and tuning can take it from 285 up to 330+. Or starting in '98 the LS1 replaced the LT1, which would be more work but more aftermarket parts and tuning support.
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