intake mainfold switch

Any thoughts on switching out a 4.0 '98 intake manifold for a 99+ mainfold? I have read that the later manifold is larger and switching dramatically improves horsepower. When doing this do other things need to be changed as well?

I did the swap from my 95 to a 00 intake and it really didn't change that much. It idles and accelerates a little smoother but seat of the pants I really couldn't tell the difference!! Hope that helps!

1995kamikazeXJ said:

I did the swap from my 95 to a 00 intake and it really didn't change that much. It idles and accelerates a little smoother but seat of the pants I really couldn't tell the difference!! Hope that helps!

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I did this on my 96 the same time as a APN header. Also didn't nitice much. I also have a donaldson airbox so my intake is unrestricted. I figure that upgrading my cat and muffler will be when I really notice a difference.