I found one manufacturers test pipes will fit 03-08 model years but then another manufacturers test pipes say they only fit 03-05...so if the dimensions are the same wont anyone's test pipes fit any year from 03-08?

 

03 to 06 are the same , 07 and 08 are the same

 

Turns out, manufacturers sometimes lie. Sometimes, they are also just that stupid.

 

Why is everything for the 07-08 twice the price as 03-06 parts.

 

Before creating any thread you should read this entire thread:

https://my350z.com/forum/2003-2009-n...questions.html

Your question would have been answered here:

https://my350z.com/forum/3688103-post31.html

 

The HR motor was fairly limited production. Typically, a smaller market will mean higher prices. Hell, the entire Z platform has higher prices than a lot of other performance imports.