Hi flow cat idea

[Chuck 98 RT/10]

I think it's time to swap my stock cats for high flows. Mainly for the reduction in heat but HP increase is always welcomed. Being the case what ideas do any of you have regarding 3-inch cats with reducers to the 2.5 inch stock pipes?

 

[99 R/T 10]

How about just sticking in a 2.5" straight pipe? I bet you will enjoy the new sound along with the extra 15 HP.

 

[Chuck 98 RT/10]

I already have one loud Viper. I like the muffler delete sound on the RT/10.

 

[Dom426h]

How about just sticking in a 2.5" straight pipe? I bet you will enjoy the new sound along with the extra 15 HP.

that 15hp is all up top though...
downside being loss of low-end, and the harsh sound that comes with no cats.
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2 more options:

if you have a 2.5" system, why not just use 2.5" Cats?

or if you want to really lose some heat, just replace the cats with something like a moroso spiralflow. It will keep the sound down and provide a little backpressure to keep the low-end.(this is just a theory, havnt dyno test myself...)

I imagine Anything is better than stock cats. Hell, i couldnt take the heat even with the old oval roe cats...

 

[Chuck 98 RT/10]

if you have a 2.5" system, why not just use 2.5" Cats?

or if you want to really lose some heat, just replace the cats with something like a moroso spiralflow. It will keep the sound down and provide a little backpressure to keep the low-end.(this is just a theory, havnt dyno test myself...)

I imagine Anything is better than stock cats. Hell, i couldnt take the heat even with the old oval roe cats...

I have not heard the Moroso spiralflows. Have you?

 

[dave6666]

I have not heard the Moroso spiralflows. Have you?

That sounds like a poser question Chuck.

Very disappointed.

 

[Dom426h]

i have only heard clips on youtube. search the VCA for moroso spiral flow for much disscusion on them. make sure to separate spiral flow to get results as spiralflow will yield nothing.

 

[RTTTTed]

I hate Cats. I dislike the heat they create and the hp they waste. Having a Gen2 is a huge benefit because of the rear exit exhaust. The length of the tubing causes a mellow sound for our cars that can't be achieved with the side pipes. Like Dave I was going to go to side pipes to save weight and allow me to build a diffuser plate on the rear of the car.

However, since I like the sound of my Corsa track exhaust and the only other 'perfect' sounding cars I've heard are other Corsa track exh (loud and not for everyone) I decided that I'm keeping the rear exit exhaust.

[media]http://www.youtube.com/watch?v=EQ1SvlIqmP4&feature=related[/media]

Chuck I had Roe Hiflows and Random-Tech Cat-back on my 98 GTS with stock exhaust manifolds. If you like quieter that combination was great. Loud idle with no drone under 2000rpm. WOT was not too loud and sounded pretty good.

[media]http://www.youtube.com/watch?v=7Ioq41bZFxc[/media]

As you can probably notice the Corsa inside is louder than the Random-Tech outside the car.

Ted

 

[dave6666]

Contrary to you deciding that I went to side exhaust to save weight and build a diffuser, the person that made those mods on that car did not do so for that reason, and is quite happy with the sound of said side exhaust.

So, when you paint your hood vents white I'll worship your exhaust preachings.

Deal?

I hate Cats. I dislike the heat they create and the hp they waste. Having a Gen2 is a huge benefit because of the rear exit exhaust. The length of the tubing causes a mellow sound for our cars that can't be achieved with the side pipes. Like Dave I was going to go to side pipes to save weight and allow me to build a diffuser plate on the rear of the car.

However, since I like the sound of my Corsa track exhaust and the only other 'perfect' sounding cars I've heard are other Corsa track exh (loud and not for everyone) I decided that I'm keeping the rear exit exhaust.

[media]http://www.youtube.com/watch?v=EQ1SvlIqmP4&feature=related[/media]

Chuck I had Roe Hiflows and Random-Tech Cat-back on my 98 GTS with stock exhaust manifolds. If you like quieter that combination was great. Loud idle with no drone under 2000rpm. WOT was not too loud and sounded pretty good.

[media]http://www.youtube.com/watch?v=7Ioq41bZFxc[/media]

As you can probably notice the Corsa inside is louder than the Random-Tech outside the car.

Ted

 

[Leslie]

I wasn't sure which way to go so I went with RTTTTed's suggestion for my GTS and did the corsa exhaust with high flow's.

Interior is much cooler, loud enough for me to enjoy it on the street, and it REALLY gets loud at the track! Perfect.

 

[RTTTTed]

Contrary to you deciding that I went to side exhaust to save weight and build a diffuser, the person that made those mods on that car did not do so for that reason, and is quite happy with the sound of said side exhaust.

So, when you paint your hood vents white I'll worship your exhaust preachings.

Deal?

Sorry Dave, you misunderstood me. "I was going to go with side pipes like Dave." The weight saving and non-interference for air flow and a rear diffuser was MY idea and I wouldn't presume to guess why you do your mods.

Ted

 

[RTTTTed]

I wasn't sure which way to go so I went with RTTTTed's suggestion for my GTS and did the corsa exhaust with high flow's.

Interior is much cooler, loud enough for me to enjoy it on the street, and it REALLY gets loud at the track! Perfect.

Glad you like it Leslie. You really need louder at the track so that you can intimidate all the other drivers that get in your way. The Helmet requires extra loud exhaust.

Ted

 

[Chuck 98 RT/10]

I'm leaning towards the highflows. I already have a loud tracker, this is for my street ride. Thanks all for the input.

 

[Tom F&L GoR]

The spiral flows are straight-thru mufflers that instead of the usual fiberglass packing around the perforated pipe have a spiral corkscrew around the centered non-perforated pipe instead. So presumably some exhaust goes through a straight, smooth walled pipe and some goes around and around that pipe.

I had high flow cats and switched from bullet style fiberglass packed mufflers to spiral flows. It was much louder. Much louder all the time louder. Went from loud bothering neighbors to loud and drone bothering driver. It's the only time I wore earplugs to drive. Took them off.

But on the good side, they are inexpensive.

 

[eucharistos]

highflows.... this is for my street ride.

for sound and no funk

 

[GTS Bruce]

I have headers,high flow and corsa from Jon B. Many compliments on sound and some think its loud. I had no cats with headers and corsa for about 2 years. Its alright inside the car and at cruise or low speeds. With no cats it is barely warm however when you're on it it sounds like the main straight at Lemans. You can be heard a mile away. NO BS. Yes there did seem to be a loss of low end torque too with no cats unless you were WOT. I like loud and the sound was good but its a better sound with the high flows and more torquey in the lower rpm range. Why not get a set of used headers from Jon B, a corsa ,cats and go 3" all the way. You will kick yourself for not having done so sooner. GTS Bruce

 

[GTS Bruce]

PS: depending on year with no cats you will need syms like I did on my 01. Bruce