IAME 175 SSE, Should I run the exhaust spacer?

I need help deciding if I should continue to use the exhaust header spacer. What are the pros and cons of running this spacer? I’m a club racer and value reliability over peek horsepower. our rules do not require this spacer. Thanks for your feedback.

It depends on to what extent you’re looking to manage reliability. If it were me I would remove the spacer and throw it in the trash. It will raise the power band by 1,200+ rpm, and the engine will just run better overall. Might there be some reduced longevity as a result of the higher rpm? Perhaps…but I think any difference in longevity is negligible.