necessity of a high flow cat?

[ninzee]

hey guys just wondering if a high flow cat is a must to a good full exaust and what sort of power will i be loosing by using a stock cat. the exaust consists of 2 1/4 extractors and a 2 1/4 catback for a D16A8 CRX all stainless steel mandrel bent.
cheers

[JDM.Power]

yes a hi flow cat will make a difference

[geeang]

There are too many variables for someone to tell you how much power you would gain with a high flow cat, but a high flow cat is definately necessary if you want a GOOD exhaust system.

[johnprocter]

just curious i have a titanium catback exhaust, is it possible for me to get a high flow cat? cause i heard they can't weld steal/SS with titanium or something along those lines

[geeang]

They could easily just weld flanges on the cat so that it bolts onto the catback, most Honda's are setup with a cat that is bolted on and not welded in place.

[saikou27]

hey guys just wondering if a high flow cat is a must to a good full exaust and what sort of power will i be loosing by using a stock cat. the exaust consists of 2 1/4 extractors and a 2 1/4 catback for a D16A8 CRX all stainless steel mandrel bent.
cheers

yes get one. the cat is one of, if not the most restrictive part of an exhaust system

[ninzee]

thanks heaps guys.. any suggestions i.e magna flow, x force??

[aaronng]

On a D16A8, make sure that you have the need for that extra flow capacity. If you are not maxing out the exhaust flow, then the gains from the high flow cat will be low.

[90LAN]

just keep it stock
so you wont get pulled over for it and get defected and complain
better spend your money else where
wont make much off a difference anyway

[saikou27]

thanks heaps guys.. any suggestions i.e magna flow, x force??

any quality brand such as magnaflow or x force will be fine :thumbsup:

[GIPONU]

or metalcat

[FastFwd]

wonder how much different between the three

Normal Cat
Hiflow Cat
Decat Pipe

Would be good to see a dyno result

[saikou27]

i remember reading an article were they tested exactly that using a d16y7 or y8. the highflow cat gave a 3hp increase, the metal highflow cat 6hp and test pipe at 8hp or something along those lines. ill see if i can dig up the article again

[GIPONU]

isnt a testpipe only advances on turo applications?

[ninzee]

i thort test pipes were illegal if not highly likely 2 get u defected

[FastFwd]

test pipes are highly illegal...not defected. More like "tow your car home" and a possible $10,000 fine. My car currently has one only for tuning perposes as im not driving my car daily anymore. but removing the cat to a decat made a huge difference. Also gives you car a nice black paint job on the rear from all the carbon.

[yourfather]

LONGCAT IS LOOOOOOOOOOOOOOOOONG

http://img6.imageshack.us/img6/774/longcat.gif

seriously for a D16 don't even bother man.

it's way too much money for bugger all gain.

[saikou27]

well in short there is no "necessity" for a highflow cat or any exhaust modifications at all for that matter. theres no doubt that it will give you some power gains. its entirely up to you whether you deem the price to performance ratio worthy or not

[FastFwd]

Being that there is limited Bolt on upgrades for NA and if your trying to scrape as much as you can out of your motor without having to get into the hardcore upgrades i would deem it as a half decent upgrade and if your getting an exhaust system at the time and having to buy a bigger cat for your new exhaust i also consider the extra dollars spend doing it the right way would be worth it also.

[joyride]

if it were me, i would be looking for a used high flow cat for cheap. like some of the other guys above said, it wouldnt make a BIG difference to an NA car.

[lookingforboost]

cats do wear out and become more restrictive we romed my brothers cat to see if there was a power difference and there was a noticable power difference in the higher RPM range

[EGJOE]

go to the wreckers and pick up a vn or earlier commodore cat cheap and enough for your application.

[saikou27]

go to the wreckers and pick up a vn or earlier commodore cat cheap and enough for your application.

i would strongly urge u not to do the above :thumbdwn:

[EGJOE]

i would strongly urge u not to do the above :thumbdwn:

Flows much better then stock and is a popular budget mod for nissan skylines RB20 and Rb25. Why do you think it will be no good on a d16? The last time I did one i used an old cat of a sr20 its even better then a jdm b18cr cat.

For the cost its a good upgrade bang for your buck. As if you would bother spending $300 or so for a high flow cat for this application. You can spend half the price and acheive same result. I'm speaking from experience not guess work, have tried and gained results.

[mr180sx]

hahahah!! Shutdown!

You cant state your opinion without elaborating on it. LOL:thumbsup:


i would strongly urge u not to do the above :thumbdwn:

[saikou27]

Flows much better then stock and is a popular budget mod for nissan skylines RB20 and Rb25. Why do you think it will be no good on a d16? The last time I did one i used an old cat of a sr20 its even better then a jdm b18cr cat.

For the cost its a good upgrade bang for your buck. As if you would bother spending $300 or so for a high flow cat for this application. You can spend half the price and acheive same result. I'm speaking from experience not guess work, have tried and gained results.

why would u buy a 2nd hand cat of a commodore its just stupid. as somebody mentioned before cats wear out and i doubt that a 20 year old commodore cat will be beneficial at all. what a joke to even suggest that u have tried it and felt gains. if u really want to, u might as well go buy a new normal replacement cat ( not that it would do much) for a commodore because it would cost next to nothing anyway. if u had half the experience u claim, u would know that a good high flow cat would greatly benefit the OP's system of full headers and a mandrel bent system seeing as how the cat would now be the biggest restriction in his system

i would also assume the OP would like something better than a used commodore cat seeing as how they have extractors and a mandrel bent system

[EGJOE]

why would u buy a 2nd hand cat of a commodore its just stupid. as somebody mentioned before cats wear out and i doubt that a 20 year old commodore cat will be beneficial at all. what a joke to even suggest that u have tried it and felt gains. if u really want to, u might as well go buy a new normal replacement cat ( not that it would do much) for a commodore because it would cost next to nothing anyway. if u had half the experience u claim, u would know that a good high flow cat would greatly benefit the OP's system of full headers and a mandrel bent system seeing as how the cat would now be the biggest restriction in his system

i would also assume the OP would like something better than a used commodore cat seeing as how they have extractors and a mandrel bent system

I'm talking bang for buck! I guess there must be alot of other idiots out there then. Tell me how do cats wear out?
Stock d series cat 2' or less in and out commodore cat around 2.25 to 2.5 in and out which one will flow more? How much a second hand cat worth $50 good value. Talking bang for buck not the best that money can buy.

Not going to bother further arguing my point. Dont question a persons experience if you dont know them and oh and im not suggesting I'm telling how it is.

[saikou27]

I'm talking bang for buck! I guess there must be alot of other idiots out there then. Tell me how do cats wear out?
Stock d series cat 2' or less in and out commodore cat around 2.25 to 2.5 in and out which one will flow more? How much a second hand cat worth $50 good value. Talking bang for buck not the best that money can buy.

Not going to bother further arguing my point. Dont question a persons experience if you dont know them and oh and im not suggesting I'm telling how it is.

so u think just because its bigger means it flows better. it depends on the cells per inch and commodores have more so they're are more restrictive. please by all means feel free to put old, used, clogged up, 20 year old commodore cats on ur car and leave the good ones for the rest of us.

[rbk_212]

I'm talking bang for buck! I guess there must be alot of other idiots out there then. Tell me how do cats wear out?
Stock d series cat 2' or less in and out commodore cat around 2.25 to 2.5 in and out which one will flow more? How much a second hand cat worth $50 good value. Talking bang for buck not the best that money can buy.

Not going to bother further arguing my point. Dont question a persons experience if you dont know them and oh and im not suggesting I'm telling how it is.

how do cats wear out? are you serious?

catalytic converter substrate can melt, warp, crack and the subtrate can come loose from the housing

a 20 year old cat would be epically stupid, and the flow of a cat is measured by the amount of cells per inch it has not how large the actual body is

[EGJOE]

Use your common sense you can see if its stuffed, believe what you want.

[SHU-ES1]

a highflow cat will give you better exhaust flows at higher rpm, but might make it more laggy during lower rpm. i just put a 100cpsi on my d17, and the higher revs are more free but i find it lags slightly at the lower revs now. but, all in all, i like having that extra punch (minimal) up top where it counts i guess. to answer the ops question, i think a high flow cat helps for a good complete i/h/e setup but some might disagree that the gains a minimal considering the money spent on one. btw, i picked up my venom 100cpsi cat for $150 and no CEL. woot!

[mr180sx]

Commodore Cat FTW!!:thumbsup:

[TYPE-ONE]

lol i love this thread

[preludacris]

lol @ buying a 20 year old cat.

where is the cheapest place to buy metal cat? i'm after one.

[SHU-ES1]

are you from melbourne? i have this guy who sells venom 100 cells psi metal cats if you're interested. pm me, ill give you his contact.

[Riviera]

if you can afford it buy one, dont be a tight arse unless its a cheap sh!t just
knocked it together system...

oi these are good man

http://i167.photobucket.com/albums/u148/Riviera001/catwtf.jpg

[preludacris]

i'm specifically after the brand 'metal cat'.

any body got good deals on them out there ?

[shitbox]

D16A8
Found in:
1988-1995 Civic/CRX/Concerto (UK/Europe/Australia)
1992-1995 Rover 216/416 GTi(UK/Europe)
1993-1997 Rover 216 SportCoupe (Europe)
Displacement : 1,590 cc (97 cu in)
Bore and Stroke : 75 mm × 90 mm (3.0 in × 3.5 in)
Compression : 9.5:1
Power : 125 hp (93.2 kW, 127 ps) @ 6800 rpm
Torque : 108 ft·lbf (14.9 kg/m, 146 Nm) @ 5900 rpm
Valvetrain : DOHC (4 valves per cylinder)
Fuel Control : OBD-0 MPFI
ECU Code : PP5
Gearbox : L3

[edit] D16A9
(Same as D16A8 but without a catalytic converter)

Found in:
1988-1991 Concerto (UK/Europe)
1988-1991 CRX 1.6i-16(UK/Europe/South Africa)
1988-1991 Civic 1.6i-16(UK/Europe/South Africa)
1989-1992 Rover 216/416 GTi (UK/Europe)
1992-1995 Civic Si (Peruvian version)
Displacement : 1,590 cc (97 cu in)
Bore and Stroke : 75 mm × 90 mm (3.0 in × 3.5 in)
Compression : 9.5:1
Power : 130/137 hp (96.9 kW, 132 ps) @ 6.800 rpm
Torque : 108 ft·lbf (14.9 kg/m, 146 Nm) @ 5900 rpm
Valvetrain : DOHC (4 valves per cylinder)
Redline: 7200 rpm
Limit: 7800 rpm
Fuel Control : OBD-0 MPFI (92-95 OBD-1)
ECU Code: PM7 (92-95 P29)
GearBox : L3 Cable type (92- 95 S20)



from wiki

[FastFwd]

if thats correct, thats swashed this thread forshore.

[reedyek4]

this could be an absolute noob question...but does installing a highflow cat increase exhaust volume over the standard?

[rbk_212]

this could be an absolute noob question...but does installing a highflow cat increase exhaust volume over the standard?

not the volume of gas no, it just allows it flow more freely

[reedyek4]

i meant in terms of noise volume?

[rbk_212]

^ oh right lol sorry

no it wont, not in any noticeable way anyway

[SHU-ES1]

i think it depends on your exhaust setup, if you already have an aftermarket catback exhaust it will probably make it louder. increasing flow generally increases the sound output. if its a stock setup, it shouldn't make much difference. but then again, why would you open up your flow with a hiflow cat just to restrict it again after it so i'm assuming you already have a aftermarket catback.