why does motordyne need v3-v4 revisions for their test pipes n exhausts? they should try and get it right on the first try, or the 2nd at most

 

Because they don't just sit back on their laurels, they are constantly after the best product.

Remember there are manufacturing tolerances, on the 370 in particularly, there seems to be a lot in the gearbox mounting, there is only so much testing you can do when it shows no problems.