De-cat exhaust system

[aucorium]

Hi guys , has anybody had a de-cat done on their yaris , if so have you had any problems? any info will help as i want to de-cat my 1.3.

Thanks

[Capagotks]

i know a friend who de-catted their RX-7. Here (and probably in most parts of the world) it is illegal to remove the cat, as it removes most of the toxic gasses from the exhaust. (im pretty sure you can take it off for show cars/race cars). You will get a significant HP increase, but it is easy to notice if you have it off because if you rev it, flames might start coming out (and not just the occasional small one, i mean FULL ON) and your eyes start watering if your in a confined space/revving it up at the lights (but mainly for the people behind you)

[thomasward00]

Remember that our stock engines were designed to operate with a certain amount of back pressure, taking the cat off some stock engines will cause premature valve seal failure, it's not worth the gain, and besides it will kill your lower end.

[BailOut]

As Capagotks mentioned, the catalytic converter is there to greatly lessen your vehicle's emissions. If you remove it you will be dumping a lot of noxious emissions straight into your local atmosphere.

[aucorium]

thanks for all the advice guys , i really appreciate it!

[WRBlue]

OBDII cars (every car made post-1996) have 2 O2 sensors, one before and one after the cat to verify cat performance. Remove or gut the cat, you'll get a check engine light.

A high flow cat flows just as much as a straight pipe, doesn't give the CE light, and will pass a sniffer test.

There is other issues with gutting a cat, including turbulance and killing yourself slowly with the nasty crap that goes into a cat.

i know a friend who de-catted their RX-7. Here (and probably in most parts of the world) it is illegal to remove the cat, as it removes most of the toxic gasses from the exhaust. (im pretty sure you can take it off for show cars/race cars). You will get a significant HP increase, but it is easy to notice if you have it off because if you rev it, flames might start coming out (and not just the occasional small one, i mean FULL ON) and your eyes start watering if your in a confined space/revving it up at the lights (but mainly for the people behind you)

Thats something specific to a rotary. Because of how the work, alot of gas enters the exhaust and ignightes easily.
Scooby's do it too, cause they are a boxer. Especially bouncing off the rev limiter.
Most other cars it takes something wrong with them to do it.

[Capagotks]

speaking of rotaries, do you think onw would fit in a yaris, mounted sideways, and even if the front bumper had to be extended?

[jdium]

speaking of rotaries, do you think onw would fit in a yaris, mounted sideways, and even if the front bumper had to be extended?

Absolutely, if you get the chance, check out the size of those lil engines. Tiny. But you're wallet will have to match the size...and you have to consider that you can't run FWD, as far as I know, there are no FWD rotories worldwide, so the swap would have to include a RWD conversion...but I'd love to see this done, in pretty much every platform...ooohhh the fun possible with 10k redlines and turbos :eek:

[Black Yaris]

only thing that is still stock on my exhaust is my cats, and only the cats... everything b4 and after has been opened up to larger diameter pipe.... and no CEL's

[WRBlue]

Absolutely, if you get the chance, check out the size of those lil engines. Tiny. But you're wallet will have to match the size...and you have to consider that you can't run FWD, as far as I know, there are no FWD rotories worldwide, so the swap would have to include a RWD conversion...but I'd love to see this done, in pretty much every platform...ooohhh the fun possible with 10k redlines and turbos :eek:

A 12A is smaller than a beer keg ;) lol

But there was a FWD rotary. A crappy NSU, the Ro 80. The engines were crap - needed rebuilds at 30k, and all the cars came with an auto.

You could adapt a FWD tranny to a Rotary, but it'll be pricy.

Then there was the Norton Commander and the Suzuki RE5 - Rotary powered motorcycles. Those would definatly fit :D There are ways to adapt them to power a car FWD, but the Suzuki was only a 500cc making 60hp... It'd be alot lighter, but it would be hard to get over 120hp out of it. lol

[Capagotks]

what about a Suzuki GSX1300R (Hayabusa) engine? its not a rotary, but produces 129kw (175 HP) and its only 1299 cc, 4-stroke, four-cylinder, liquid-cooled, DOHC, 16-valve, TSCC. (from wikipedia), so I reckon it would easily fit in the yaris, and the 2008 model is bigger with 1340 cc, 4-stroke, four-cylinder, liquid-cooled, DOHC, 16-valve, TSCC and a compression ratio of 12.5:1 (up from 11:1). Then turbo it. then you've got yourself a deathtrap on wheels.

[Capagotks]

or even better, the Kawasaki Ninja ZX-14, with 1,352 cc Liquid-cooled, 4-stroke In-Line Four, 12:1 compression ratio, DOHC, 16 valves, fuel injection, digital ignition, electric starting 140 kw (187 hp) @ 9,500 rpm; 147.1 kw (200 ps)(197 hp) @ 9,500 rpm with RAM air; 154 Nm (113.5 lb/ft) @ 7,500 rpm and a 6-speed transmission.

[jdium]

what about a Suzuki GSX1300R (Hayabusa) engine? its not a rotary, but produces 129kw (175 HP) and its only 1299 cc, 4-stroke, four-cylinder, liquid-cooled, DOHC, 16-valve, TSCC. (from wikipedia), so I reckon it would easily fit in the yaris, and the 2008 model is bigger with 1340 cc, 4-stroke, four-cylinder, liquid-cooled, DOHC, 16-valve, TSCC and a compression ratio of 12.5:1 (up from 11:1). Then turbo it. then you've got yourself a deathtrap on wheels.

Sounds kinda like this:

http://www.youtube.com/watch?v=xLVQtK04lig

SmartCar with a GSXR1000 in it...

[Capagotks]

pretty much. fool everyone in the bike lanes....:laugh:

[eTiMaGo]

bike engines are nice, but they need to be revved up to crazy speeds to make much useful power. That's not too much of a problem on a bike as weight is very low, but a car is far heavier, wouldn't make things very sluggish at lower RPMs?

Although, I suppose, with this kind of swap, you wouldn't want to drive at low RPMs ever!

[Motorhead6T5]

If you delete the cat you will need a mil elim,since the ecu cannot be reflashed to turn the rear 02 circut off(yet). A mil elim is a malfunction indicator lamp eliminator. Its baisicly a resistor that tells your ecu that it is getting a clean reading ,it is pluged into the rear o2 harness.

[Black Yaris]

If you delete the cat you will need a mil elim,since the ecu cannot be reflashed to turn the rear 02 circut off(yet). A mil elim is a malfunction indicator lamp eliminator. Its baisicly a resistor that tells your ecu that it is getting a clean reading ,it is pluged into the rear o2 harness.

or you can do it the easy way and get defoulers for a few bux

[Vanderkitten]

I decatted and race-piped the Yaris last week... top end is GREAT... low end is brutally underserved. It did improve over 3-4 engine cycles, and it's in preparation for some un-normal aspiration, but now I am pondering Supercharger over Turbo!

[Capagotks]

bike engines are nice, but they need to be revved up to crazy speeds to make much useful power. That's not too much of a problem on a bike as weight is very low, but a car is far heavier, wouldn't make things very sluggish at lower RPMs?

Although, I suppose, with this kind of swap, you wouldn't want to drive at low RPMs ever!

Hey did you get my last PM about the yarisworld sticker and my paypal address?

Anyway, a turbo would help along with racing filters and the like, and maybe the transmission could be modified to adjust the ratio and reduce the top speed/increase acceleration. And I would remove the yaris transmission and get a mechanical LSD and use a custom transmission (or add in an idler gear to have a 6 speed forward and reverse, 250km backwards would be awesome.... :burnrubber: )

[Capagotks]

I decatted and race-piped the Yaris last week... top end is GREAT... low end is brutally underserved. It did improve over 3-4 engine cycles, and it's in preparation for some un-normal aspiration, but now I am pondering Supercharger over Turbo!

in your situation i would go with a supercharger to help the low end. do they make one for the 1NZFE (or whatever engine you have?) Im designing a system for My D&T (Design and technology) major project at school, it involves removing the cat but without affecting the low end power. i'll put up some plans here when I get it working (still in the design stage)

[regime]

the yaris has a 1.5 thats needs back presure to make the little bit of torque it has....

if you havn't done alot of engine work, i wouldnt open up the exhaust too much...

[CASTREX]

I decatted and race-piped the Yaris last week... top end is GREAT... low end is brutally underserved. It did improve over 3-4 engine cycles, and it's in preparation for some un-normal aspiration, but now I am pondering Supercharger over Turbo!

Hey Vanderkitten, I really will like to see some pics of your exhaust set up! when ever you have some time.
I will most probably decat my Yar as well. Is the race pipe custom made??

To what diam did you open your pipes? The Yar is 1 3/4" cat back (I think)... So I was thinking first to delete the cat but kept a resonator and then open the entire pipe just a little bit up to 2" back to the muffler (I have Dynomax Turbo exhaust waiting just to keep things quite)

I hope such exhaust set up won't have a terrible effect on the low end tq.

[Spades]

wow....not only is de-catting illigal in most places...on new cars it f--ks up the computer unless you get a piggyback to trick the o2 sensor or reflash the computer. besides, with the amount of high flow cats on the market for race applications, WTF would you wanna de-cat a car with 105 horsepower???

I mean really guys...when you are pushing 400+ horsepower and a 4" diameter high flow cat isnt pushing enough air through, then lets worry about it, chances are at that point the car wont be street legal anyway...untill then, do yourselves a favor and save some cash and (dare i sound like a pot smoking hippie) stop dumping your "octane boosted" weapon r intake mostly stock econoboxs emissions into the atmosphere...

EDIT: get rid of the damn resonator first, not only is the stupid thing restrictive it tones your exhaust down...if you have to straightpipe something get rid of that pile of scrapmetal.

[chongopants]

So i take it, it would be a bad idea to simply remove everything before the cat? Where is the second O2 Sensor exactly? I haven't looked real hard at the exhaust yet. But I would like to let it breath, and I honestly dont care about emissions or sound. Just pure performance. Anyone have any ideas that wont damage my engine let me know.

Thanks

[BailOut]

I honestly dont care about emissions
Spoken like a true Texan. :thumbdown:

[chongopants]

Yup, still dont care... its a yaris, my 81 f-150 with no smog sytem and 300hp puts a LITTLE bit more out than the yaris, oh and so does my honda lawnmower... so meh, keep your thumbs down....

[chongopants]

oh and my yaris bets better mpg than yours so ... unless you have a $10,000 electric conversion, I am getting mid 50s in mpg in town...

[severous01]

first off...it's illegal

second...you will get almost no gain out of the cat removal, you'd be better off with a catback

third, the cat is there to remove NOx, CO1, hydrocarbons, and converts it all into CO2 and water. if you wanna be an ass and contribute to pollutants in the atmosphere go ahead. i hope someone finds you and puts u in jail and fines you the full 250k.

i'll tell you this, and you can take it for what you want. i've done extensive research and on newer and older cars, i've worked in shops and custom shops, and i've tried it several ways and with several different cats and styles. the very best thing you can get is a cat from random technologies. it's a full pass, hollow cat. i dont know how it works but it does, even at WOT. second would be a magnaflow cat as they're cheap as 20 bux on ebay for a 2.25". third and last option, if you're a backyard mechanic with a torch and some extra pipe laying around and you're a cheapass....you can gut or delete the cat alltogether. and be an idiot.

i have a 383ci camaro, full length headers, borla catback, and 2 magnaflow 3" cats. i make more power with the cats than without. and it cost me a total of 40 bux plus 10 to weld the 'adapters' from the stock units on. i tried open headers, exhaust, with and without cats...and with todays fuels and addatives it's better to leave the cats on.

here's the link to random tech if you're really wanting to delete the cat...but you're more worried about saving money than the environment so i doubt you'll be using it:
http://www.randomtechnology.com/products.html

[chongopants]

yup.

thanks.

[ddongbap]

Spoken like a true Texan. :thumbdown:

I don't either. And I'm from California.

[YarisPR]

Does the yaris come with 2 cats and a resonator?

[06silveryaris]

speaking of rotaries, do you think onw would fit in a yaris, mounted sideways, and even if the front bumper had to be extended?

Some guy in my town had put one in a 99 tercel and kept it front wheel drive. They made a plate for the tranny to use the toyota one. I know they had issues with the intake side of the engine. It was carburated, but now the car is full track car and made rear wheel drive and of course still rotary powered. BTW don't remember if it was 12a or 13b

[06silveryaris]

Does the yaris come with 2 cats and a resonator?

Yes

[fmicle]

Spoken like a true Texan. :thumbdown:

+1 :clap:

And then they bitch about the Chinese building one new coal power plant every week :smile:

[fmicle]

I don't either. And I'm from California.

I wonder if this attitude would change if you guys had to breathe that crap yourselves... But hey, I guess it's alright if some poor kid somewhere will develop some respiratory disease because of the smog, as long as it's not your kid...

[BailOut]

I wonder if this attitude would change if you guys had to breathe that crap yourselves... But hey, I guess it's alright if some poor kid somewhere will develop some respiratory disease because of the smog, as long as it's not your kid...
... or if they had lived through the destructive acid rain events of the 1970's, which were mostly solved by making catalytic converters compulsory.

Those that do not learn from history are doomed to repeat it. :frown:

[cali yaris]

a 2 year old thread sprouts to life with all-new nastiness. :clap:

[ddongbap]

Since a little Yaris is the source of all the health problems in the world.

I think the hyper mileage section needs your input guys. Get to it.

[ozmdd]

Before this gets any uglier, can any of the cat-removal advocates cite anything that shows a HP or other performance gain from running w/o a cat? Everything I've heard/seen on small-displacement, non FI motors is that its around 0.3% difference, so why bother?

[Nexus1155]

YOURE KILLING THE OZONES!!! Please save the tree vs. the 1HP gain and get yourself a better suspension setup you will benefit betterssss

[aucorium]

well , been doing research , and it seems that a full exhaust system , header and de-cat gives the @2NZFE 1300cc 9 kw more power !! dyno tested here in RSA , thats on approx 50mm exhaust , thats 12 HP , and with a dastek uniQ it jumps to 12 kw , not to bad for a 1300cc , i bet the 1500cc will do much better

[ozmdd]

well , been doing research , and it seems that a full exhaust system , header and de-cat gives the @2NZFE 1300cc 9 kw more power !! dyno tested here in RSA , thats on approx 50mm exhaust , thats 12 HP , and with a dastek uniQ it jumps to 12 kw , not to bad for a 1300cc , i bet the 1500cc will do much better

Again, not to dispute your info, but that sounds about the same as the gains I got from a CAI and an axle-back exhaust w/ an underdrive pulley. No changes to my exhaust manifold or cats/midpipe at all. I don;t think the cat gives you even 1 hp.
I'd love to see something that shows different results.

[aucorium]

Again, not to dispute your info, but that sounds about the same as the gains I got from a CAI and an axle-back exhaust w/ an underdrive pulley. No changes to my exhaust manifold or cats/midpipe at all. I don;t think the cat gives you even 1 hp.
I'd love to see something that shows different results.

no prob buddy , remember , this is on a 1.3 , not a 1.5 , gains will differ. :-)

[YarisPR]

My dad used my Yaris (1 cat removed) to get the inspection of his Z3 (it doesn't pass inspection do to emissions) and my Yaris passed :laugh:

And Yes, emissions laws here are easily bend / broken / worked around LOL

[why?]

automobile emissions are the least of anybodies problems. Seriously. Anyone who has such worries is completely clueless.

And has never been stuck behind a bus, semi, or any other large vehicle which has absolutely zero emissions reducing devices.

[ozmdd]

automobile emissions are the least of anybodies problems. Seriously. Anyone who has such worries is completely clueless.

And has never been stuck behind a bus, semi, or any other large vehicle which has absolutely zero emissions reducing devices.

Diesel emissions are chemically different than gasoline. Just because they are visible doens't mean they are "dirtier."

[lilredrocket]

This is true NOx is the worst thing that comes out of gasoline buring motors and is clear. Diesel does not put off NOx when burnt but does produce soot which actually settles out of the air and lands on the ground.

[hatchbackkid82]

Someone correct me if i'm wrong but i'm pretty sure the first one is the cat and the second one down is the resonator. I don't remember seeing 2 resonators and cat when i did my mid-pipe

Does the yaris come with 2 cats and a resonator?

[BailOut]

automobile emissions are the least of anybodies problems. Seriously. Anyone who has such worries is completely clueless

That has got to be the most clueless statement I've read on YarisWorld this week, and that says a lot.

Have you ever experienced acid rain (http://en.wikipedia.org/wiki/Acid_rain#Adverse_effects)? Have you ever had your taxes used to clean up both the economic losses and ecological mess it leaves behind? Does it not bother you that these things are attributed to premature deaths and higher cancer rates?

Is it not totally ridiculous that these things are easily preventable, are mandated to be prevented, that we are all given the tools on our OEM builds to do just that, and that some incredibly selfish people choose to remove those protections for no quantifiable reason whatsoever?

Some may wish it wasn't a big deal. Some may wish we didn't have to live with it. Some may wish that what they do doesn't affect others. But we're all old enough to realize that wishing something doesn't always make it so.

[posaunemeister]

Someone correct me if i'm wrong but i'm pretty sure the first one is the cat and the second one down is the resonator. I don't remember seeing 2 resonators and cat when i did my mid-pipe

Yeah, that's what I thought, too. I don't know what the whole double-cat talk is all about. I've only seen one that precedes the resonator.

My former Suzuki Reno HB had two cats and a resonator. The first cat immediately came after the exhaust header and before the flex-pipe and the other cat (which actually looked like a resonator) lead into the true resonator. But yeah, I only noticed one cat...

[ddongbap]

It goes CAT o2BUNG CAT RESONATOR.

[why?]

That has got to be the most clueless statement I've read on YarisWorld this week, and that says a lot.

Have you ever experienced acid rain (http://en.wikipedia.org/wiki/Acid_rain#Adverse_effects)? Have you ever had your taxes used to clean up both the economic losses and ecological mess it leaves behind? Does it not bother you that these things are attributed to premature deaths and higher cancer rates?

Is it not totally ridiculous that these things are easily preventable, are mandated to be prevented, that we are all given the tools on our OEM builds to do just that, and that some incredibly selfish people choose to remove those protections for no quantifiable reason whatsoever?

Some may wish it wasn't a big deal. Some may wish we didn't have to live with it. Some may wish that what they do doesn't affect others. But we're all old enough to realize that wishing something doesn't always make it so.

Acid rain wasn't caused by automobile exhaust. It was caused by many many different things. First and foremost was factory smokestacks with zero filters.

Guess what? They can't do that any more. Now factories have to spend lots of money on filters for their smokestacks.

No matter what anyone does to a Yaris, its emissions can never compare to a bus, or a semi, or even a light truck. All of which has emissions that are not regulated in the cases of busses or semi's, or are less regulated in the case of light trucks.

Blaming acid rain or any environmental problems on passenger automobiles is simply moronic, or it is used as a tool to control the mass public, and use them to suit someone's political agenda.

[ddongbap]

Acid rain wasn't caused by automobile exhaust. It was caused by many many different things. First and foremost was factory smokestacks with zero filters.

Guess what? They can't do that any more. Now factories have to spend lots of money on filters for their smokestacks.

No matter what anyone does to a Yaris, its emissions can never compare to a bus, or a semi, or even a light truck. All of which has emissions that are not regulated in the cases of busses or semi's, or are less regulated in the case of light trucks.

Blaming acid rain or any environmental problems on passenger automobiles is simply moronic, or it is used as a tool to control the mass public, and use them to suit someone's political agenda.Don't forget SUVs. And the Prius batteries which'll burn a hole to China.

Don't forget that cows also fart.

Don't forget PETAisPITA.

[why?]

Now I have no problem with people saying clean air is important, because it is. But the technology in cars today make their emissions negligable.

I wouldn't ever personally remove my cat, because I do agree that race ones are actually better for power gains, and as was mentioned, small engines need backpressure for low end tourque.

But trying to put up the personal responsibility for the environment is just blatant hipocrisy and bs. The man who invented global warming puts out more emissions in a week then most of us do in an entire year.

[fmicle]

Don't forget that cows also fart.

:bellyroll:

[Mouse]

And people also breathe

[fmicle]

While I agree that buses, trucks and factories pollute more, there are simply so many automobiles, that their impact cannot be negligible.

Clean and super-green countries such as Austria and Switzerland have speed limits on the Autobahn (Freeway) to limit pollution first and foremost. Germany is the only country I know of that has no speed limits on the Autobahn, but that's because the Auto industry is big and has a powerful lobby.

[Mouse]

There are speed limits on the Autobahn in Germany in congested areas. It's mostly parts of the Autobahn that are in the country side that do not have a speed limit.

[fmicle]

There are speed limits on the Autobahn in Germany in congested areas. It's mostly parts of the Autobahn that are in the country side that do not have a speed limit.

I lived in Germany from 2000 until 2004 before moving to California :smile:

Usually, around every Autobahn exit (Ausfahrt) the speed limit is 120 km/h. Most mass produced vehicles are electronically limited to 250 km/h mainly for insurance purposes, except for sport cars and high-end models (which are much more expensive to insure of course). The German traffic laws recommend a maximum speed of 130 km/h and some insurances won't pay damages if the accident happened above this speed.

Additionally, any mechanical changes to the car must be approved by TUV and listed on the registration papers otherwise they void the insurance.

[Marfulion]

My dad used my Yaris (1 cat removed) to get the inspection of his Z3 (it doesn't pass inspection do to emissions) and my Yaris passed :laugh:

And Yes, emissions laws here are easily bend / broken / worked around LOL

that cus all you have to do is fork over some mofongo and your good to go:laugh:

[fmicle]

My dad used my Yaris (1 cat removed) to get the inspection of his Z3 (it doesn't pass inspection do to emissions) and my Yaris passed :laugh:

And Yes, emissions laws here are easily bend / broken / worked around LOL

The California DMV caught about 7 smog check stations in the Bay Area (Santa Clara county) doing "clean piping" last week and removed their licenses...

[YarisSedan]

Couple things i noticed in this thread. A high flow cat basically is a hollow pipe with only about 5% of the catalist in a normal catalitic converter just coating the inside of it. It does really next to nothing to me its just a gimmic to make people feel better. How do you think oem cats cost about 500 dollars or more but those aftermarket high flow cats are as cheap as 50 bucks. Cause less expensive material used.

So your o2 sensor will still trigger a code for catalist threshold below efficiency P0420. Because your cat is less efficient the computer detects it and thinks there is a problem.

Also the amount of NOX produced by our car without a cat i would imagine is in the thosuands. Compared to one iwth a cat which would be maybe 50 or even zero. So that means the pollution your one yaris puts out is equivilent to 3000 yarises on the road that have cats. Just to put things in perspective to you.

[advocate]

Okay while the earth is good and we all love living, can we get back onto topic?

This has been posted in the performance section. No one cares about mother nature in this subforum. People care about... performance! So if you've de-cat'd and have a dyno or anything else about it that you'd like to add then add it!! We would love to read about some actual results, not opinions that belong in the political sub-forum.

[BailOut]

This has been posted in the performance section. No one cares about mother nature in this subforum.
It's just not that simple. When what you do has a negative, lasting impact on everyone in your region, it is a public act. You cannot put on such a public display and not expect feedback - much of it negative.

The air we breathe and the water we drink is much more important than some selfish person's baseless desire for more horsepower, no matter how you try to spin it.

[advocate]

Dude, cows farting ended this thread. Really.
http://en.wikipedia.org/wiki/Cows#Environmental_impact

There's probably hundreds of millions of them. And they fart all the time.
Edit: Wow there's over a billion. Gotta love In' N' Out!!
http://en.wikipedia.org/wiki/Cattle#Population


Plus, the world won't be lasting that much longer anyways, humans are on average too stupid. We care more about skin color and the languages people use to communicate instead of the fact that we are all made up exactly the same crap on the inside.
http://www.examiner.com/x-25013-Portland-Conservative-Examiner~y2009m12d2-Iranian-nuclear-weapons-soon-to-be-a-reality


Might as well enjoy life while it still exists.

[aucorium]

sjjoo , this topic has run away quite a bit , LOL !!

[aucorium]

anyone thats done a decat get a good power increase?

[06silveryaris]

The power gain will be very minimal if any these cars make little power to begin with. On a track car or turbo engine difrent story not the case for the Yaris. You will probably loose backpressure and will probably loose torque but make minimal hp at mid to top end

[aucorium]

The power gain will be very minimal if any these cars make little power to begin with. On a track car or turbo engine difrent story not the case for the Yaris. You will probably loose backpressure and will probably loose torque but make minimal hp at mid to top end


i spoke to one of the guys here in SA that did a yaris exhaust ,de-cat and header and they got a extra 9kw

[aucorium]

i dont think a cat can effect back pressure , but the boxes you use can.

[Jacksonville]

Spoken like a true Texan. :thumbdown:

Mind your Bunny Ranch... and dont be so quick to judge Texans.

[GianniVRS]

On my old Glanza 4EFTE 13cc, removing the cat was one of the first mods we used for high flow and the increase in engine response was noticeable. has anyone tried it on the 1NZFE N/A not turbo JDM (trd turbo m or any after market etc etc) ? on the Honda's with an uprated intake & Exhaust Mani + decat we do wonders, does our 1NZFE benefit ? (ok i know it is ilegal etc etc and it does harm etc etc)

[cali yaris]

i dont think a cat can effect back pressure , but the boxes you use can.

Anything that restricts exhaust flow affects back pressure.

[UberSilver]

speaking of rotaries, do you think onw would fit in a yaris, mounted sideways, and even if the front bumper had to be extended?

Would fit easy, you'll need to have an adaptor made to mate with the trans.

I put a 13b ported and blown, into a 71 morris mini. With close to 300 hp, that mini was a real beast.:thumbsup:

[chaditotx]

Does anyone know where I can get some real lead additive? Not the fake stuff either.