ZRE Cat. Back Exhaust System

[SHIRE.ZRE]

Hi Guys,

Was visiting my friends at Hi-Tech Mufflers today for something completely un-related to the Corolla, in fact it was to discuss the design of a completely new exhaust system for the new model X-Trail and I dropped off the exhaust gasket for them to start designing the headers/extractors.

Was too lazy to drive my X-Trail, so decided to take my Corolla there instead :)

Here we're standing and discussing the ZRE Corolla and Hi-Tech said, it's indeed a nice car and here I am trying to find a nice exhaust tip to weld it on the exhaust to pretty it up a bit, 1 hour later I drive out with a full cat. back system on the car with quad exhaust system and the kids were over the moon (and so was I). hahahahaha :D

Here it is (sorry, some pics been taken with my mobile at Hi-Tech shop, as I didn't have the camera with me)

The factory muffler on its way to the bin. And that long section is the pipe coming from that monster resonators we have under the ZRE. I first thought it was the cat. converter, but when when we un-bolted the exhaust system and had a closer look, it was nothing but a big resonator to muffle the sound of the factory exhaust system and the cat. converter was further up. We decided to keep the big resonator in place to keep the system quiet, but it can be removed for those who like a noisier exhaust system....I don't.

I decided to go with a dual exhaust set-up system, as it has been proven to free-up the exhaust a bit more and provide more power, which is what I was after, especially in the low and mid RPM ranges.

We also decided to put one additional resonator on each side to make the system sound a bit more quiet but purring nice at the same time, which is exactly what happened and what was achieved.

On the drive back home, I was amazed at how much more responsive the car was, there was no throttle lag as I would have experienced before when trying to force it to change gears (mine is Auto) and the acceleration was simply amazing. There is definitely an increase in power that can be felt.

The system sounded very nice indeed, it doesn't drone when driving or idling at the lights and you can hear its nice purr when you drive close to barriers.

Took some pics of it when we got home:

It has certainly transformed the Rolla for sure and now that I started (un-intentionally) the performance mods on this Rolla, they gonna continue, so here comes the CAI. hahahahaha

I would definitely recommend this cat. back system to any ZRE owner. The good part about it is that it doesn't impact the factory warranty at all ;)

P.S. Am not sure how different the ZRE Hatch exhaust system is, but if it is the same as the ZRE sedan, then this system can be fitted to your car within 2 hours max. and while you wait.

[Rusty Bucket]

Looks awesome mate. Love the dual twin tips. Glad you got a decent performance gain too..

[Ascendant Rice]

Sedan must have dif exhaust system, on the hatch the muffler is combined with the second cat underneath the cars mid section and the thing in your first pic is actually the resonator on the hatch.

Love what you've done keep up the good work!

-will

[SHIRE.ZRE]

Sedan must have dif exhaust system, on the hatch the muffler is combined with the second cat underneath the cars mid section

Are you sure? That bulky rocket in the middle if the car (if you have one) is actually a resonator and you would see an O2 sensor just before it and if you look further up, you would see the black cat. converter with another O2 sensor before it as well. My assumption is that the first cat. converter is part of the exhaust manifold.

and the thing in your first pic is actually the resonator on the hatch.

Yes, it is the resonator on the sedan as well as was located at the back of the car behind the factory muffler tip.

[GTL05T]

Good Work Champ... Looks The Part...

[Ascendant Rice]

Sedan must have dif exhaust system, on the hatch the muffler is combined with the second cat underneath the cars mid section

Are you sure? That bulky rocket in the middle if the car (if you have one) is actually a resonator and you would see an O2 sensor just before it and if you look further up, you would see the black cat. converter with another O2 sensor before it as well. My assumption is that the first cat. converter is part of the exhaust manifold.

and the thing in your first pic is actually the resonator on the hatch.

I'm positive!

The guy that did my exhaust showed it to me he said that at first he assumed it was a resonator but infact its actually the muffler also if u look into it u will see the second cat converter, its integrated into the muffler.

will

[SHIRE.ZRE]

That's strange Will because a cat. converter needs to have a ceramic core. This bulky resonator is completely empty inside, so it can't be a catalytic converter. Had your exhaust guy run a wire through it he would have realized it's not a cat.

[Whitey1212]

Wow, just wow! I love it!

I had my car up on a hoist a few weeks ago. I should post the photos.

I'm really tempted you know! Damn you shire, I'm blaming you for all my negligent spending on my car. You're so inspiring :P

Edited October 14, 2009 by Whitey1212

[SHIRE.ZRE]

Wow, just wow! I love it!

I had my car up on a hoist a few weeks ago. I should post the photos.

I'm really tempted you know! Damn you shire, I'm blaming you for all my negligent spending on my car. You're so inspiring :P

hahahaha :) Sorry mate to inspire you that much LOL :)

Looking at your set-up I can confirm that it is 100% the same as the sedan ZRE, so this system would fit it like a glove. The system starts from the flange after that big resonator all the way back to the twin tips. The pipe size of the factory set-up is very restrictive at 1.25". Hi-Tech have fitted 2" pipe all the way through.

[Ascendant Rice]

=/ most of it is hollow but if u look at it the cat is b4 the welded section ><! I will ask toyota on friday when i get my car serviced!!!!!!

[Whitey1212]

Wow, just wow! I love it!

I had my car up on a hoist a few weeks ago. I should post the photos.

I'm really tempted you know! Damn you shire, I'm blaming you for all my negligent spending on my car. You're so inspiring :P

hahahaha :) Sorry mate to inspire you that much LOL :)

Looking at your set-up I can confirm that it is 100% the same as the sedan ZRE, so this system would fit it like a glove. The system starts from the flange after that big resonator all the way back to the twin tips. The pipe size of the factory set-up is very restrictive at 1.25". Hi-Tech have fitted 2" pipe all the way through.

Oh nice.

Now I'll be asking that age old question. How much? :P

I thought that the cat was up the front near the extractors? The one in the middle is just a resonator/muffler isn't it?

Edited October 14, 2009 by Whitey1212

[SHIRE.ZRE]

Here is a pic explaining where the cat. converter is:

Only one of the O2 (Oxygen Sensors) is showing in this pic, the other O2 sensor is before the cat. converter further up. I also think that this is the second cat. converter, as there would be another one built into the exhaust manifold as part of the extractors.

The price of this cat. back system is $980.00 (plus GST) supplied & fitted and it carry's 10 years warranty which is more than any factory warranty on any exhaust system I have ever seen. The entire system is Stainless Steel (not mild steel) which means it will never rust!

It's black because I told them to paint the pipes and the mufflers for a "sleeper look" ;)

[One-pager]

I think that's pretty expensive for a muffler back system. It's not cat-back since you left the muffler behind the cat stock. It looks great though!

[SHIRE.ZRE]

I think that's pretty expensive for a muffler back system. It's not cat-back since you left the muffler behind the cat stock. It looks great though!

True, it's expensive indeed, but I pay for quality, 10 years warranty and knowing that it will give results. I didn't want to remove the resonator behind the factory cat. at seemed to be doing it's job. Had I needed more ground clerance I would have gotten rid of it. It's still on the cards though as I'm going back to Hi-Tech next week sometime to make the system a bit more quiet.

Those of you coming to the meet-up this Saturday will be able to hear it and let me know if you think it's loud and requires fine tuning. I am testing this system at the moment and might have to go back to Hi-Tech a couple of more times to have it operating exactly as I want.

[Ascendant Rice]

I think that's pretty expensive for a muffler back system. It's not cat-back since you left the muffler behind the cat stock. It looks great though!

True, it's expensive indeed, but I pay for quality, 10 years warranty and knowing that it will give results. I didn't want to remove the resonator behind the factory cat. at seemed to be doing it's job. Had I needed more ground clerance I would have gotten rid of it. It's still on the cards though as I'm going back to Hi-Tech next week sometime to make the system a bit more quiet.

Those of you coming to the meet-up this Saturday will be able to hear it and let me know if you think it's loud and requires fine tuning. I am testing this system at the moment and might have to go back to Hi-Tech a couple of more times to have it operating exactly as I want.

Looking forward to seeing it, i shall bring a change of pants aswell!

[SHIRE.ZRE]

i shall bring a change of pants aswell!

I started to drive the Rolla with 2 as well LOL :D The power increase is something that I didn't expect at all. I wish we could arrange a dyno day or something ;)

[johnnieboi]

Is it really that loud? Seems like your really trying to silence it down hardcore. I know it does improve performance, but only a couple of kw's, not that massive of a power jump. Good work anyway.

[SHIRE.ZRE]

Is it really that loud? Seems like your really trying to silence it down hardcore. I know it does improve performance, but only a couple of kw's, not that massive of a power jump. Good work anyway.

Maybe it's just me, as I got used to drive around in my x-trail which also has the twin set-up and it's much quieter than the Rolla. My wife is not complaining but I can hear it :) If I base the power increase from a cat. back system on the xtrail which was 9KW (at the wheels) for a 2.5LT engine (dyno proven), I believe the Rolla gained a bit more than 2KW at the wheels, it certainly feels like it but it has to be dynoed for more accurate figures.

I will put it on the dyno when I do the CAI.

[Ray89]

mmm interesting give me figures as soon as u get a dyno... ive seen a white zre sedan wif exhaust system sounded ok.... prefer the twin loop setup lol = ascendant rice white zre hatch good work bro :) but anyways back to power figures lol no offence but ive doubt theres much gain each car is different so yeah :) good luck

[Ascendant Rice]

mmm interesting give me figures as soon as u get a dyno... ive seen a white zre sedan wif exhaust system sounded ok.... prefer the twin loop setup lol = ascendant rice white zre hatch good work bro :) but anyways back to power figures lol no offence but ive doubt theres much gain each car is different so yeah :) good luck

Cheers bro

[SHIRE.ZRE]

=/ most of it is hollow but if u look at it the cat is b4 the welded section ><! I will ask toyota on friday when i get my car serviced!!!!!!

Did you ask Toyota about that muffler under the car? what did they say?

[SHIRE.ZRE]

mmm interesting give me figures as soon as u get a dyno... ive seen a white zre sedan wif exhaust system sounded ok.... prefer the twin loop setup lol = ascendant rice white zre hatch good work bro :) but anyways back to power figures lol no offence but ive doubt theres much gain each car is different so yeah :) good luck

No offence taken mate. I will let an owner of a stock ZRE sedan drive my car and decide if there is noticeable power gain as a resault of this system or not. They will notice the difference straight away (if there is any). I know I did and my "butt dyno" never fails :D

[DJKOR]

Good job mate. Glad to hear you are satisfied. Quad tips worked out alright. The whole power gain thing is like an endless argument until you can show solid proof. My opinions still stay in line with what Ray said in that:

no offence but ive doubt theres much gain

As long as you're happy though, that's all that counts.

[Ascendant Rice]

=/ most of it is hollow but if u look at it the cat is b4 the welded section ><! I will ask toyota on friday when i get my car serviced!!!!!!

Did you ask Toyota about that muffler under the car? what did they say?

oh! i completelly forgot!!!! i was too busy hassling them about my drive shaft =/ ill ask when they change my shaft.

[SHIRE.ZRE]

Thanks Daryl,

Solid proof of the gain will be provided in due course, provided I can find a stock ZRE owner to dyno their car as stock, so we can compare the gains more accurately that way. A power gain is a power gain, regardless of how much it is, for NA engine it's noticeable, hence my feedback.

Anyway, I just came back from Hi-Tech and decided to add another small resonator in-line to completely quieten down the system and I am completely satisfied with noise level now. That little bit of drone which some people like didn't go well with my sensitive hearing LOL :)

P.S. We checked that rocket of a muffler again and I can confirm 100% that there is cat. converter there whatsoever, had there been a cat. converter there we would have seen the O2 sensor mounted after it, which is not the case.