How Much Power Does a Cat-Back Lid and Filter LS1 Car Have

Question:

How much will the above exhaust system affect my cars torque and horsepower? I intend to add an SLP breather with a low restriction filter element. What do you think of these 2 mods? The LS1 should breathe better and thus run better.

asked by: Dan L

Expert Reply:

As the owner of a 98 Pontiac Trans Am with an LS1 and an automatic transmission I am pretty familiar with the gains associated with the basic mods of these cars. Magnaflow claims you will gain about 14 horsepower and 18 ft-lbs of torque. That seems a bit generous, but it will definitely sound better and you will pick up power.

Lid and air filter is usually worth another 10 horsepower and torque as well. We carry a filter similar to the one you are looking at.

Most lid and catback cars with auto transmissions put down around 300 rear wheel horsepower and 310 torque, so I would say you would be right in that range.

Another free mod you can do to help get you a little more power is called the "free ram air" mod. It's pretty easy to do and makes a noticeable difference.

If you have any other questions on mods feel free to email me back with the goals for you car and I would be more than happy to help you. When I bought my car it was basically stock and now it has heads/cam, big stall, every bolt-on, built transmission and suspension work.

expert reply by: Jameson C