High-flow cat converter for cheap

[negatron]

Hey hey,

If I can plonk the cat converter from a 1jzgte (a twin turbo charger) unto my exhaust system will it do me any good?

I'm thinking that the 1ZZE may not produce enough pressure to push it through properly but i'm thinking it may turn out to be a cheap hi-flo cat.

Your thoughts?

[Mintos]

Firstly "plonking" will not be a zero cost exercise unless you are handy with a grinder and welding or have the flanges.

I thought that cats were universal for all cars, in which case you may want to look for some stuff from the wreckers off some of the new high end Holden & Fords, they come stock with high flow cats i read somewhere.

I know nothing of the 1jzgte cat and am slightly perplexed as to why you would seemingly want to add more back pressure to your exhaust system.

In all honesty i dont think a different cat other than the stocko one is worth it unless you dont plan on staying N/A. I have a brand new high-flow cat and it doesnt give me an extra few kilowatts or anything, that is for sure.

[rolla02]

It's unlikely to fit .

I think the Rolla Cat is quite close to the Manifold, so I can't imagine it would be bolt on.

And as Mintos said it won't give you any gain in power.

Then again we could all be wrong.

[justin_es]

i have a supa flow cat converter on my stivo its HEAPS louder cus of it

not sure about the levins or whatever you have

but the stivo cats(mine is 05 so also not sure about 03-04) have baffles in it to help with noise

so if yours is the same it will make it louder with a different cat

Edited October 9, 2005 by evl_50a

[DANZZT231]

Standard cat is efficient enough according to many exhaust shop I went to. Change it when its blown, it that ever happens that is.

[Buddha]

I spoke to a few different exhaust shops around the northside of Brisbane, and while they can differ immensely in terms of pipe size, mufflers, etc, they mostly agree on one thing ... the standard Corolla cat and resonator flow extremely well, to the point that none of them suggested changing the cat and only one suggested removing the resonator, and then only if the exhaust note is too soft with it on.

As it turns out, certainly to my ears, its perfectly fine right where it is.

[SILVABULLIT]

Standard cat is efficient enough according to many exhaust shop I went to. Change it when its blown, it that ever happens that is.

←

Standard cat on the Stivo is larger than what is on most cars with an engine of almost double the capacity and the shape of it as you would see is not a hinderence of the flow like what you would see under a commodore etc with an almost square shaped cat. Hence why the CES system bolts on after the cat as they have looked at it and said for the extra cost of a new cat and the minimal gains that may/may not be made is certainly not worth the cost.

[negatron]

Hmm,

so the question is, is it worth my while hunting for a stivo cat to plonk unto my 1zze?

[lucio_libre]

What you really need is for CES to make you a custom one :P

[MR22ZZ]

You may be able to find a Celica one from a Wrecker if you're lucky :D

[Orbit]

I can confirm what Danz said. Prior to fitting my exhaust system i did a lot of mailing and phoning around to get the may info i found and every reliable source told me to just keep the original because one that would really be better then the stock one would cost me a fortune for a really small gain (1, maybe 2 horses).

So i ended up with a 60mm line from the cat to the rear with a Rally group N silenser at the end. It's loud but really ok when cruising. Only when really hot and while breaking on the engin it gets LOUD betwean 4 and 3 K. I'm sattisfied with it because the gain in power was significant and clearly translated in a faster 0-100 and a faster 400m.

[shaohaok]

I can confirm what Danz said. Prior to fitting my exhaust system i did a lot of mailing and phoning around to get the may info i found and every reliable source told me to just keep the original because one that would really be better then the stock one would cost me a fortune for a really small gain (1, maybe 2 horses).

So i ended up with a 60mm line from the cat to the rear with a Rally group N silenser at the end. It's loud but really ok when cruising. Only when really hot and while breaking on the engin it gets LOUD betwean 4 and 3 K. I'm sattisfied with it because the gain in power was significant and clearly translated in a faster 0-100 and a faster 400m.

←

since when did group N and silencer were used together :P

[Northy]

Hmm,

so the question is, is it worth my while hunting for a stivo cat to plonk unto my 1zze?

←

as buddah mentioned the stock cat is fine, when i had the 1zz i was told the same thing buy a few diff places.

[SILVABULLIT]

What you really need is for CES to make you a custom one  :P

←

CES actually modify standard cats to flow more than the suposed off the shelf hi flow cats. :P For a lot cheaper :P

[Mintos]

What you really need is for CES to make you a custom one  :P

←

CES actually modify standard cats to flow more than the suposed off the shelf hi flow cats. :P For a lot cheaper :P

←

I can "modify" standard cats too - for i bet even cheaper than CES, its called a freestyle exhaust and involves more cutting than welding. :P

[Orbit]

 

since when did group N and silencer were used together :P

←

?

Since when not ? In several cases they even need to use the stock catalityc convertor ...

[DANZZT231]

Maybe its far worth changing into hi flow cat once u turbo or s/c your car.

[negatron]

Man, after seeing all those cars burn up (poor volkswagon :( ) i'm going to start dropping all these on the cheap mods ideas

[Orbit]

Maybe its far worth changing into hi flow cat once u turbo or s/c your car.

←

And again I need to agree. The exhaust for a NA engine is way more critical then the exhaust for a car with forced induction. On a NA car you need some kind of pressure to get the gasses out at a high speed. Thats the reason that you schould really think when choosing the diameter of your exhaust system. The speed of the gasses getting out schould be not to fast, nor to slow (faster in a thin pipe, slower in a larger pipe). Why? Because the exhaustgasses create somekind of suction in the stage where the exhaustgasses exit the cilinder. And this suction is created by speeding the exhaust gasses. When your exhaust is to big it will slow the gasses down and thus create less suction wich leaves less room for new and fres air/fuel mixture in the cilinder. When you pipe is to small it will just create to much pressure and thus again hindering the suction.

This is also the reason that exhausts on 2 stroke engines in general (from RC nitro engines over lawnmowers to racebikes) are extremely important for the performance of the engine. Since they don't have valves they rely completely on presure and suction to get the old gasses out and the new in.

Hope it is understandable :)

For a turboed car it is way simpeler. You already have a huge problem with your exhaust, namely a turbo is in it's way ... Thus the only task for your exhaust is to give the turbo as less pressure as possible at it's exit side. So fit the largest tubing you can find ... The suction thinghy is now the problem of the downpipe which is also the reason a downpipe can make a serious difference on a turbo's car, also when the exhaust already has a large diameter.

SC cars folow the rules of NA cars, just larger diameters then for NA. Which is logical, if you want to have the same speed of the exhaust gasses you will need more diameter because there are simply more gasses in comparison to a NA car with the same displacement.