Will I gain any horsepower with High flow Cats

[FLX109]

I know it should run cooler under there but do I gain anything with Random Tech Cats?


FLX109

 

[HOdbleFman]

Take 'em out.

 

[2BADD 4U]

You will gain 5-7 hp with r/t ceramics and similar with r/t metal ...

I just installed Belangers and r/t ceramics, the side sills are cool now, and the cockpit temp is MUCH cooler.

The sound was a nice improvement also.

Dave

 

[Dimitrios]

is there a HP gain with NO cats? also i hear lots of vipers that make a popin sound when letting off the gas and some even shoot flames out of the rear and they are not Super charged. is that because of the NO cats?

 

[Chuck 98 RT/10]

is there a HP gain with NO cats? also i hear lots of vipers that make a popin sound when letting off the gas and some even shoot flames out of the rear and they are not Super charged. is that because of the NO cats?

Yes
Yes

 

[LIVIPER]

How do the guys who take out their cats pass emissions?

 

[ViperRay]

You live in a state where they don't check

 

[Marc Lublin]

You can't pass if they check. Before anyone takes them out completely, listen to someones first. Mine are out and the car is louder than I would like, but the idiot in me doesn't want to give up a couple of horses and make it quieter.

 

[Streak]

There is something you guys need to understand.....
If your current exhaust is flowing good, even with cats, you will not gain ANY horsepower or torque. I took the stock cats off and only gained about 4 torque and 1 horsepower .....because it was flowing enough.

Now when you force induce it or put heads and cam...then you will gain more due to the need to increase the flow.....

Steve
Speed Motorworks

 

[Ron]

Steve,

Are you referring to a Viper?

Thanks

 

[ViperJoe]

Take a look through a STOCK cat and then a RT hiflow.....nuf said

 

[ZX1100]

How do the guys who take out their cats pass emissions?

Mine are out and passed emissions. As long as the computer says everything is ok they won't sniff it. Depends on year of car though. Here in IL if it's older than a certain year then they sniff it automatically.

 

[Streak]

Ron,

Ohhh yes. I have worked on exotics for years. I have a 97 gts. Without getting really technical, if the exhaust is flowing more than the the engine is able to produce horsepower, then their will be no gain from installing a high flow cat or taking off the cats.

For instance....A 97 I worked on. It had headers and exhaust with stock cats. I took the cats off and gained NOTHING because it was already flowing enough exhaust. Same dyno, same correction factor. It depends on the condition of the cats also....

Steve
Speed Motorworks

 

[NascarDave]

My 2000 R/T passed without cats. They hookup OBDII and make sure all tests are running. If so, no sniffer as ZX1100 says. Also, make sure no "check engine" light.

Mine pops and shoots flames

DN

 

[Ron]

Joe,

Would love look, but don't happen to have a set of high flows in my garage at the moment. Agree with Steve though, if OEM cats give you what you need, flow wise, what difference does it make? Cooler running perhaps... nice but no HP in cooler running.