If you want to make over 350HP you will need to get away from the cast iron log style manifolds. Look for tubular manifolds like the ones offered by full race or AJP or SRT.

You will spend more up front if you just buy a kit from one of them but it will all fit no questions asked.

If you go the custom route like I did you will still spend over $5000 to get over 350HP.

What are your power goals?

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