Can you get a bigger throttle body for your 1991 civic hatchback or how hard is it to change the whole intake manifold you got the d15b2 eng an the throttle body come strait up instead of to pass side?

Yes, you can upgrade to a bigger throttle body for your 1991 Civic hatchback with a D15B2 engine, but compatibility will depend on the specific throttle body you choose. Changing the entire intake manifold is also possible, but it can be more complex, as it may require additional modifications to fit and align properly. Ensure that any new components match your engine's specifications and consider the tuning required to optimize performance. Overall, both upgrades can enhance power, but they may require some mechanical skill and knowledge.