Honda5272

I have a 1999 Honda Civic d16y7 4-2-1 header no cat and a N1 muffler short ram intake
I need to try and improve my gas mileage and low end power. It bogs when I step on it. Would a ebay high flow cat do it some good for gas mileage, low end power and back pressure and such things?

doctorake

None of those things will make power.

sleepyaccord96

here my .02 cents... i agree with doctrake


secondly, i bought a magnaflow high flow race cat brand new for almost 200 dollars... i used it on a low miles jdm h22a for about 18k miles and i got a blockage in my exhaust and upon inspection i realized the cat had come apart. i got it warrantied out. I drove another 9k miles and BOOM it exploded going down the road while i was at 6500 rpms.

Rule of thumb= do not buy a magnaflow cat of any type.



also, a cat will not help your situation one bit.

purgat0ry

iTrader: (3)

Also, backpressure = myth, it's been proven.

That doesn't mean chop off your exhaust entirely, it just means don't worry about it.

dadawof

please explain your back pressure statement

because any disruptions in the tubing/piping of the exhaust can negatively affect the flowing/sucking action that is getting the exhaust fumes out and the fuelair mixture in the combustion chamber

doctorake

Just google backpressur myth

B_Swapped93

lol putting money into a 100hp engine

TripleLude

If you need a cheap cat, Magnaflow works. It is considered high flow because the inside diameter is larger. If you don't have a matching header and exhaust, you will not take advantage of the Magnaflow cat.

I've been running Magnaflow cats for years (one is 10 years old) and never had one explode or warrantied.

Honda5272

So don't buy one then? I got harassed by the Sheriffs the other day saying my car was to loud.

purgat0ry

iTrader: (3)

It's loud because you have got a HYYYUUUGGEEE fart canister on the back man

No catalytic isn't helping either, it's there for emissions, it can indeed end up making the car not nearly as loud due to extra resistance and **** within the exhaust system to end up making it quieter

B_Swapped93

just get one ! the car smells like **** I bet... I got one just cause of stop n go traffic and it would pour in to the cabin . plus there is no performance to be gained or lost by getting one.

Marvin1985

iTrader: (5)

Say that to boosted cars.

doctorake

There still isn't much loss on a turbo car with a high flow cat. At least with my other two turbo cars, don't have a turbo civic though.

JDM-Punk

sadly... this :/

honda tuning did a dyno review several years back on a b16. they litterally gained 1whp from switching to a high flow cat and then another 1whp when going to test pipe... so i personally wouldnt bother, unless you plan to have it in your build, past your current motor. also keep in mind there is two different type of high flow cats and most ebay "high flow cats" are not actually cats, but mini resonator pipes.

EsotericImage

iTrader: (8)

I am using a small hi-flow cat just to reduce noise levels on my 3" exhaust. It does help a little with noise until im at WOT. If I do get pulled over, I have a cat to show the officer and thats all.

but for normal cruising it sounds like it should.

Mines not a mini resonator, but has a core that looks like rolled up cardboard which you can see thru. Mine is one made for vettes as they have limited space.

Honda5272

Idk thanks for all the help though. I mean I just want it to be a little quieter when I'm just putting around so I'm not getting harassed all the time.

estewar03

If you're already running no cat then don't waste your money unless you need one for i/m tests. It wont lower the noise level enough to be worth it, personally I'd switch your "muffler" out for a real muffler like magnaflow or flowmaster or better yet if you want it quiet go for a tanabe madalion muffler.
As far as magnaflow cats I have been using them for years with ZERO issues what so ever, they are great.
Or you could have a resonator welded inline on your exhaust pipe and that will definately quiet it down allot as well.
And as far as gas mileage you definately will not gain any mpg's by adding in a cat, you're just going to have to stay out of the throttle which will be difficult w/ your current motor lol.

JDM-Punk

well if you're looking for a bit quieter, then you might want to look into a different muffler.. cops in my area mainly go for the "n1" look (but will harrass and ask about the cat if its loud).

i would get pulled over all the time when i had a n1 style muffler and never got pulled over after switching to a tanabe touring medallion (have yet to get pulled over for my apexi noir on a diff car)

Mad-Mike

iTrader: (1)

I'm using a high flow cat on my 91 civic base model. It was a last resort because the cat rusted out and I had it sitting around.

Honda5272

So in all you wouldn't buy a high flow cat?

EJ Rocket

If you live in a state that doesn't have emissions testing, I'd just get a test pipe. With a d16y7 you're not gonna feel any power difference, though. In fact, it may drop low end power a bit. HondaTuning's test found that a high flow cat nets a 4 whp gain on a B16, but a B16 responds a lot better to bolt ons than any D-series does.

TripleLude

You only get decent gains from high-flow cat if your downpipe ID and midpipe ID match the high-flow cat ID.

I have dyno proof of intake + exhaust + high-flow cat = 21% gain on a dyno. This was a B20a3.

B_Swapped93

this is still going ?