I know that a lot of people here will flame on me, but anyway I think that we have to think about the environment too.

I know that the test pipe or cat delete produce the most gains and a better engine response, but it produces a lot of pollution too.

Nowadays the High flow catalytic converters are giving almost the same gains of the test pipes, but without pollution.

Does the 5whp more (test pipe vs High flow cat) worth the environment degradation?

 

The differences from what I've seen have been about 10-15whp, so yes, its worth it to me especially considering its a LOT cheaper than a high flow cat to begin with.

 

I picked up 5 HP with a DP and high flow cat over the factory cat and DP. Pipe is pipe pretty much so,I'm guessing that even though it is "high flow" it's choking my car. I'm currently building a test pipe to remedy that situation. Sorry enviroment.

 

In this month Import Tuner the gains were minimal (1-2hp) between the high flow cat and test pipe. But they tested on a SI. What is the difference on the Evo? In California thats not even worth the potential crazy fines I'd get.

 

The SI doesn't have a turbo you are trying to spool. Besides a full exhaust on an SI is what? 5HP 10 tops. That is nothing acompared to even just a catback on a turbo car.

 

You can see in this test that the difference is not that high:
https://www.evolutionm.net/forums/sh...andom+cat+test

 

I only drive the Evo on the weekends. The rest of the time I driving a 1900 lb. 100 HP Toyota Paseo (bone stock, with lots of weight reduction) that gets over 40 miles per gallon (has the factory cat). I don't feel too bad about killing the environment two days out of the week America is starting to move away from petrol energy anyways (which is a good thing) so maybe we won't have to feel as bad about killing the environment if everyone else is driving around in alcohol powered cars while we pay $15.00/gallon at the pump for straight 93 octane =)

 

I understand that...thats why I asked what the differences on the Evo were, in terms of power. Read the post. Changing the Catback and DP are not the same as changing a Highflow Cat and test pipe in terms of power gains. If the power is anything less than 5hp I wouldn't eff with it (in Cali)

 

If I was in Cali, I wouldn't run a test pipe PERIOD, but thankfully I don't.

 

i am close on starting bolting up exhaust parts, but i don't think that i will ever run a test-pipe...

i can live with minus 10whp... As my evo is a daily driver i don't want to smell the poisonous fumes of the engine every day...

 

test pipe ftw

 

I try to respect my fellow motorists. Being stuck behind a catless car at a light is simply rude to those who breathe.

 

Get a cat. It will make your car smell less, those behind you will appreciate it, and you will be saving the environment to boot. 5-10HP is not worth it.

 

I like clean air, I'll always use a cat. Seriously, there's always someone faster; you think you're 900hp Evo is fast? Well, there's some guy with a 1500hp Vette somewhere. Heck, 500hp Busas are pretty damn fast too....

If you want more power, spend money on a go-fast part that doesn't significantly hurt emissions. Go get some cams, get a better exhaust manifold, get a 2.3L motor.... Or just go run everday and lose some weight

 

Just to clarify, the fumes are smelly and poisonous with or without the cat. (that's kinda funny if you read it just right )