18-10-2013, 12:41 PM
Tbh mate, whatever is said about manufacturers claims being optimistic etc, losing 20bhp is a significant amount that would imply a bigger problem. Best way to sort it out would be with a specialist, especially if you're keepimg it long term and want to stay NA. Getting another engine as a donor would be cheaper, but require a lot more work from you/me/anyone else daft enough to get involved and be a bigger risk (possibility of buying a duffer etc). Depends where your priorities lie.