Sergio

I mean, i cannot see why the catback portion of any exhaust system should be different from a LT1 and a LS1....
The cat is located in the exact same bottom section right ? The entire bottom is pretty similar to me but there must be some difference(s) to justify the $75 LT1 hardware package SLP charges for their Loudmouth setup.

Polo-94Z28

The LS1 and LT1's use different cat mounting locations. The LT1 single cats are farther back after the 'y' in the y-pipe, vs LS1's which have two cats farther forward, 1 cat on each leg of the 'y'... which is similar to the dual cat LT1's... but not the same by far. The y-pipe on the LS1 comes farther back torwards the rear of the car and has a slip joint, and is also closer to the middle of the car. The LT1s have a bolt/ball flange, and the joint is closer to the rocker. Basically the 70bucks you are paying for in the LT1 kit is a 's' pipe that allows you to use the ball joint on your LT1 cat, and allows you to use the slip on joint of the ls1 loudmouth... because that was what it was orginally designed for I beleive (the ls1 fbodys)

Anyone correct me if I am wrong... been a while since i installed a loudmouth... though I have done both LS and LT series...