Difference between 3rd and 4th Gen Cat Backs
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Joined: Jun 2001
Posts: 278
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From: new phila, oh
Car: 1990 RS
Engine: LS1
Transmission: T56
Axle/Gears: 3.73 9 bolt
Difference between 3rd and 4th Gen Cat Backs
What is the difference in these? I mean under the car is all interchangable so shouldnt the exhaust be the same length with the same bends. Reason I am asking is I always see 4th gen cat backs for cheap, but rarely do I see 3rd gen ones for sale.
Joined: Jul 1999
Posts: 10,950
Likes: 26
From: Orange, SoCal
Car: 1990 Pontiac Trans Am
Engine: 355 TPI siamesed runners
Transmission: Tremec T56
Axle/Gears: 12-Bolt 3.73
The part where the cat-back connects to the cat is different. Everything else is really similar. LT1 cat backs are going to be easier to bolt-up than LS1's. But you'll still need some custom work to get it to connect.
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