I have a 2003 Vette LS1. If I change the factory H pipe for an X pipe, will I see better performance??????? Is it worth it??? I plan on not changing the mufflers... As always thanks for your help.. Great forum. Joe.

the sound will more than likely change noticeably ,
but the performance on that car, with the stock mufflers being retained, is not going to be a huge improvement , in most cases, simply because the exhaust on a late model corvette, is not extremely restrictive, in its stock form, so the gains will be minimal IF the (X) USED ON A STOCK ENGINE VS the (H) it replaces


an (X) is more efficient, at blending and reducing the flow restriction to the exhaust pulse waves, than an (H) at lowering the flow restriction, and blending the sound waves, but if your not dealing with a reasonably restrictive exhaust simply swapping to the (X) from the (H) won,t gain you much but a mellower tone in the exhaust sound, if the exhaust is not at least some what restricted, so that adding the (X) reduces that restriction.

headers like these help noticeably



http://www.corvetteguys.com/dougs-long-tube-ls1ls6.html




you may want to read thru these

http://www.boyleworks.com/ta400/psp/exhaust3.html


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