free or hi flow cats?

[nik..]

hi everybody what is the best for my vqhr motor? free or hi flow cats i already have install the jwt dual pop charger there is no any other modification on my car ..i like alot the stock sound i don't want to change the exhaust, i just want the stock sound a bit louder..so what do you think???

[nik..]

any ideas ???

[Z1Performance]

Do you have, or are you planning, on an aftermarket exhaust?

[nik..]

not at the moment..but i will after a year with nismo exhaust ..
Modified by nik.. at 4:08 AM 8/28/2009

[dasoupdude]

Depending on your emission laws and how much you love your planet Earth, it all depends on whether you feel the need to get hi flow cats, or go ahead with (resonated) test pipes.

I live in florida, so I use test pipes. therefore I'm an as*hole. Yeah.

[raremotive]

gains with free flow and high flow are very minimal.. might as well make the sniffers and tree huggers happy

[NSRsheets]

Test pipes makes the car sound raspy. The high flow cats will give you the better sound minus the raspyness.

[nik..]

thanks for your help gays i think i will go for berks hi flow cats...better stock sound without any strange noises i think...

[evildky]

high flow cars are generally only good for 2-3 whp, not worth it imho

if you like the stock exhaust not you'll likley lake the aftermarket exhausts as well

[nik..]

just install the berks hi flow cats sounds great but notice i think i am not sure the power moved to higher rpm or lost some power what do you think? i have also jwt dual pop chargers installed

[RCAnismo]

just install the berks hi flow cats sounds great but notice i think i am not sure the power moved to higher rpm or lost some power what do you think? i have also jwt dual pop chargers installed

You gained like 2 hp...I doubt you would even be able to tell much of a difference with just this one mod alone.

[nik..]

ok i understand is not noticeable but is there any possibility to lost hp from the mods i have done?

[RCAnismo]

ok i understand is not noticeable but is there any possibility to lost hp from the mods i have done?

I don't think it would make it slower. It's possible it could use some tuning now but with just those 2 mods I wouldn't waste the time or money on it. Maybe something else is wrong if you've lost a lot of power.... But I'm not sure what that could be.

[SemperFiV12]

High flow cats are better in every which way than "free flow" or test pipes. Overall HP is better with HFC and powerband is improved throughout. "free flow" or test pipes will loose tq and early HP and give you radical gains at high end.

In other words get test pipes if you track your car and find yourself near redline. If not HFC is the way to go.

Unless price is a huge factor, in whic case TP will be cheaper than HFC.

TP will also be louder and raspier than HFC.

[SemperFiV12]

Also... reading on. HFC for HR engines are very responsive. You can be sure to gain more than 8-9 hp around the 11k at the 6k range and a moderat 4-9 throughout.

Should have made a big difference and freed up a lot of higher end power.

[nik..]

thanks a lot you are relay helpful also I've been driven my car a lot the last days it has a noticeable more power in higher rpm .. anyway sounds nicer different better and louder and probably that's the reason seems to me is not throttling compare the sound in lower rpm ..