Can you benefit from running no cats on a tuned motor?

[sumo]

That's with cats. I have a catted y section with my long tube headders.......and supercharged......

 

[gunslinger]

I think what the original poster wants to know is if you took the cats off your system now, what would the difference be? Keeping in mind you would of course be in another league with that blower, so I would expect it to be more dramatic in your case.

 

[JennaBear]

Stock cats are high flow... Not much to gain from just cutting them out.

Sent from my fone.

 

[sumo]

Other than sound

 

[01ssreda4]

When you say a ton of power, can you quantify in hp? I'm interested in people putting these on a Dino before and after. I'd suspect a lot of the gains you feel are also attributable to the tune I'm sure you did afterwards. In other words apples to apples would be comparing your long tubes, y pipe no cats, and tune to a guy that did long tubes, y with cats, and tune... Not to a stock system.

It had a bolt on tune before. Basically some timing and fueling tweaks, nothing major cause its a stock engine. I installed the headers and made no other changes. The power increase was immediately noticeable and only got better as the computer adjusted the fuel trims as I drove. I selected 1 3/4 headers due to me maintaining a stock rpm limit on this engine. Before the torque was good but midrange was lackluster and the engine didn't seem to like rpm. Now it builds steam all the way to shift and is begging for a higher shift point.

 

[ccapehartusarmyINF.(ret)]

there is always a gain from running no cats
cats are literally pointless even for the enviroment

 

[gunslinger]

It had a bolt on tune before. Basically some timing and fueling tweaks, nothing major cause its a stock engine. I installed the headers and made no other changes. The power increase was immediately noticeable and only got better as the computer adjusted the fuel trims as I drove. I selected 1 3/4 headers due to me maintaining a stock rpm limit on this engine. Before the torque was good but midrange was lackluster and the engine didn't seem to like rpm. Now it builds steam all the way to shift and is begging for a higher shift point.

That's some good detail. So I guess what I'm saying is I'd be curious to know what the power difference would be if you'd left on the cats when you bolted up the headers. Seems like a lot of other post are unquantifiable opinions and speculation.

 

[Countryboy07]

That's some good detail. So I guess what I'm saying is I'd be curious to know what the power difference would be if you'd left on the cats when you bolted up the headers. Seems like a lot of other post are unquantifiable opinions and speculation.

When switching to long tubes, most people go catless Y because it's simpler and cheaper. You won't be able to utilize your factory cats when you switch to long tubes. You can buy a catted Y with high flow cats if your wanting to run a set of cats, or take your vehicle to an exhaust shop and have them modify your factory Y to hook up to your new headers

 

[sumo]

Nope. Certainly cant use factory cats with LT

 

[Countryboy07]

That's a very nice looking set up! @sumo