Highflow cat okay with turbo?

[Primoce]

I'm getting tuned tomorrow. I'm debating on putting this magnaflow highflow cat on before the tune.
I want a cat because I want to keep a low profile. You know, not as loud but still a good performer.

Question is, what do you think of having a highflow cat?

 

[Prozon]

Good idea, especially if you have to pass emissions.

 

[lokibear]

I really don't know to much about boosting but to help with sound wouldn't a glass pack help?

 

[Tam4511]

no downside to it, put it on.

 

[Primoce]

I've been told that it works the turbo out?... Not pushing out as much air as a straight pipe...?
I'd really like to have it, so my car is not roaring all the time as i daily drive it...

Oh and btw

I finally got it tuned

 

[JDMxDB8]

If I had a turbo, I wouldn't use a cat. :twocents:

 

[Tam4511]

I've been told that it works the turbo out?... Not pushing out as much air as a straight pipe...?
I'd really like to have it, so my car is not roaring all the time as i daily drive it...

Oh and btw

I finally got it tuned

well how big is the piping? if its 3" don't worry about it. but you could run a straight pipe and just get a resonator.

If I had a turbo, I wouldn't use a cat. :twocents:

yeah i have 3 inch piping straight form the turbo lol.

 

[AlexD]

you would probably end up destroying that cat with a turbocharger

 

[teg9five]

you would probably end up destroying that cat with a turbocharger

I would love to hear your theory on this.


High flow cats flow very well. They have very little restriction and pass emissions with flying colors (assuming your tune isn't running hella rich). I've been running a high flow cat from summit for the last 5 years. No issues, great performance.

 

[Spawne32]

you would probably end up destroying that cat with a turbocharger

 

[Prozon]

I have no idea how a turbo might destroy a high-flow cat. The exhaust shouldn't make any difference with the turbo on or off.. the high flow cat is built for just that- HIGH FLOW. They work fairly well.

As for the piping, I think even with 2.5" you should be fine, these aren't very big motors and really do not require that much piping to get the exhaust flow out easily.

 

[AlexD]

Heres something that Josh from .. .wait for it...

TEAM INTEGRA said in a thread just like this

It's actually lean AFRs that increase temps and actually destroys the honeycomb inside a catalytic converter due to melting or cracking. The unburned fuel in a rich AFR will burn cooler but increases the amounts of unburned fuel in the exhaust. This leads to excess hydrocarbons in the exhaust stream which will plug the cat with carbon deposits. Two different types of cat failure...

That's my understanding of it

Also if rich AFRs heated the cat quickly then why would so many cars run air pumps on cold start at idle for emissions reasons? They are adding air which = more lean AFR

He seems like a pretty credible source, but I can see what hes saying.

 

[AlexD]

I would love to hear your theory on this.


High flow cats flow very well. They have very little restriction and pass emissions with flying colors (assuming your tune isn't running hella rich). I've been running a high flow cat from summit for the last 5 years. No issues, great performance.

Are you turbocharged? If not, then your situation doesnt apply to the OP's question then.

 

[Prozon]

Alex is right, the lean AFR's are what causes the heat.
That's why you can melt a piston if you are running too lean.

I think with a tune- your AFR should be perfect and you shouldn't hurt a cat.

 

[AlexD]

the thing is though, when youre tuning for part throttle AFR's you are tuning really really lean to help conserve gas mileage. On the other hand, if you tune safely, you are tuning slightly rich. In which case, you are still harming the cat.

Best method of going about this is not running a cat imo.