Experimental Exhaust System

[ELEGNT]

solid effort for the 1st day anyway man!

its just a bummer that toyota made the computer so touchy on this car...otherwise we could get away with alot more :(

[apg39]

Bugger.

Thanks for the update though!

Good Luck for day 2.

Once its done are they looking to sell off the shelf kits that we can order?

[ELEGNT]

we will pay a good price

[CHA54]

Well so far not so good unfortunately...

After a complately new system was fabricated (manifolds included, with sensor stuff so it wouldnt cause issues)... Well it did, kicking up the engine managment light and restricting engine revs. While it sounded GREAT on idle, it would keep kicking up diagnostic errors, even after spending over half the day trying to adjust it.

So we reverted back to the stock setup and started working in stages, just working from the back to the front...

After fabricating new back sections (after the stock pipe splits into 2) it sounds really meaty and grumbly, although it began to drone even at that moment. 2,000-2,300rpm would just send a massive vibration through the car, drone like hell and even induce the dash rattle. Which i NEVER had until then :S

So day 1 isnt looking so hot at the moment, but theres always day 2 :) keep ya posted, and i forgot my camera so ill get some pics hopefully.

What codes was it throwing?

[Tofuboi]

If we are able to make it work properly, im sure they'll start doing kits once its all done up nice. :)

Not sure how much tho lol.

In terms of the error codes I actually can't remember what they were now... They did come up on the little display on the ZR6 and engine light was stuck on. I assume it was throwing some sort of engine management code.

[CHA54]

the scantool you use to clear the codes should tell you exactly what they are, will help to sort the exhaust so it doesn't cause the CEL

[dave262]

Well done Tofuboi for doing what so many of us are too scared to do with the Aurions, experiment with exhausts! Will be interesting to see what can be done, especially about that crush section. The only reason I can possibly come up with as to why a crushed Y section would have been made (other than for cost reasons) would be for backpressure purposes or some method of controlling the drone. By removing this, it's anyone's guess as to what the outcome will be! Good luck!

solid effort for the 1st day anyway man!

its just a bummer that toyota made the computer so touchy on this car...otherwise we could get away with alot more :(

It is a scarily advanced ECU from reading the service manual... I read about it having dual processors and dual memory banks with each processor and memory bank crosschecking constantly for any errors and failing over if necessary! Not to mention things like soak timers that trigger off fuel tank pressure checks 6 hours after the car is turned off. Some rather impressive technology there, but unfortunately with such smarts comes limited flexibility - especially for modding :(

Makes it even harder when it's a EURO4 compliant car, since all the sensors are super-sensitive...

[SecaBoy]

glad someone is mucking around with this... :)

i'd be interested, but i'd need to be guaranteed that it'll work on the TRD with its ECU being even more sensitive than the standard aurion...

ps: jase, when are we gonna finish this intake of mine? lol

[Tofuboi]

Yeah not too sure how it'll go with the Aurion.

Hopefully next monday we can continue and see how we go :)

[SCOOTA44]

Well so far not so good unfortunately...

After a complately new system was fabricated (manifolds included, with sensor stuff so it wouldnt cause issues)... Well it did, kicking up the engine managment light and restricting engine revs. While it sounded GREAT on idle, it would keep kicking up diagnostic errors, even after spending over half the day trying to adjust it.

So we reverted back to the stock setup and started working in stages, just working from the back to the front...

After fabricating new back sections (after the stock pipe splits into 2) it sounds really meaty and grumbly, although it began to drone even at that moment. 2,000-2,300rpm would just send a massive vibration through the car, drone like hell and even induce the dash rattle. Which i NEVER had until then :S

So day 1 isnt looking so hot at the moment, but theres always day 2 :) keep ya posted, and i forgot my camera so ill get some pics hopefully.

i have had the same problem, droning in that rev range, got straight through redback mufflers,replaced centre res with 10 inch hot dog and 8 inch hotdog before the split at the back, ok when its cold but give it some stick up hills and warm the mufflers up its unbearable, and theres nearly no note at all 2500 and above,. going to try another glass packed oval muffler instead of the hotog up front, will let you know how that goes.

[Tofuboi]

Well at the moment the 'big' projects on hold. But I've taken ELEGENT's advice and went for the SuperCat Oval 8x4 Hi-Flow Muffler on the back and the burble is there. The drone is there too but its not as loud as it was initially. I can hear noise up higher in the rev range but it seems the front of the car overtakes the rear in the sound department when the revs hit about 4,000 haha.

[the_random_hero]

Well so far not so good unfortunately...

After a complately new system was fabricated (manifolds included, with sensor stuff so it wouldnt cause issues)... Well it did, kicking up the engine managment light and restricting engine revs. While it sounded GREAT on idle, it would keep kicking up diagnostic errors, even after spending over half the day trying to adjust it.

So we reverted back to the stock setup and started working in stages, just working from the back to the front...

After fabricating new back sections (after the stock pipe splits into 2) it sounds really meaty and grumbly, although it began to drone even at that moment. 2,000-2,300rpm would just send a massive vibration through the car, drone like hell and even induce the dash rattle. Which i NEVER had until then :S

So day 1 isnt looking so hot at the moment, but theres always day 2 :) keep ya posted, and i forgot my camera so ill get some pics hopefully.

i have had the same problem, droning in that rev range, got straight through redback mufflers,replaced centre res with 10 inch hot dog and 8 inch hotdog before the split at the back, ok when its cold but give it some stick up hills and warm the mufflers up its unbearable, and theres nearly no note at all 2500 and above,. going to try another glass packed oval muffler instead of the hotog up front, will let you know how that goes.

Always something I've been interested in doing to an Aurion, I'd love to see a LARGE centre muffler with just two hotdogs at the back. I think half the issue is there's so much pipe with nothing to stop some crazy reverb happening.

[Tofuboi]

Well so far not so good unfortunately...

After a complately new system was fabricated (manifolds included, with sensor stuff so it wouldnt cause issues)... Well it did, kicking up the engine managment light and restricting engine revs. While it sounded GREAT on idle, it would keep kicking up diagnostic errors, even after spending over half the day trying to adjust it.

So we reverted back to the stock setup and started working in stages, just working from the back to the front...

After fabricating new back sections (after the stock pipe splits into 2) it sounds really meaty and grumbly, although it began to drone even at that moment. 2,000-2,300rpm would just send a massive vibration through the car, drone like hell and even induce the dash rattle. Which i NEVER had until then :S

So day 1 isnt looking so hot at the moment, but theres always day 2 :) keep ya posted, and i forgot my camera so ill get some pics hopefully.

i have had the same problem, droning in that rev range, got straight through redback mufflers,replaced centre res with 10 inch hot dog and 8 inch hotdog before the split at the back, ok when its cold but give it some stick up hills and warm the mufflers up its unbearable, and theres nearly no note at all 2500 and above,. going to try another glass packed oval muffler instead of the hotog up front, will let you know how that goes.

Always something I've been interested in doing to an Aurion, I'd love to see a LARGE centre muffler with just two hotdogs at the back. I think half the issue is there's so much pipe with nothing to stop some crazy reverb happening.

Well this is the thing. With the Aurion's exhaust. It's main noise cancellation is done at the rear mufflers. It's what stops the majority of the drone. You could pretty much have just straight pipe where the centre resonator is and you won't hear TOO much of a difference if the stock rear mufflers are in place.

[DJKOR]

Well this is the thing. With the Aurion's exhaust. It's main noise cancellation is done at the rear mufflers. It's what stops the majority of the drone. You could pretty much have just straight pipe where the centre resonator is and you won't hear TOO much of a difference if the stock rear mufflers are in place.

This is also where things start to get a little funny.

See, Elgin put twin cannon style resonators on the rear of his TRD and left the centre resonator in place. This created a slightly louder tone outside of the car which sounded quite smooth. Inside the car however, it droned like crazy. It was much louder inside the car than out.

When I had my cut-out which was located just after the centre resonator, this created a deep tone which when held at around 3000-4000 RPM, would be deep enough to be heard over a good distance. It would also set off car alarms within a short distance. The way to describe it was like the drone that Elgin got, but instead of inside the car, it was outside of it. Inside the car, it sounded a little deeper because you could hear it better, but there was never any droning.

[SCOOTA44]

Well so far not so good unfortunately...

After a complately new system was fabricated (manifolds included, with sensor stuff so it wouldnt cause issues)... Well it did, kicking up the engine managment light and restricting engine revs. While it sounded GREAT on idle, it would keep kicking up diagnostic errors, even after spending over half the day trying to adjust it.

So we reverted back to the stock setup and started working in stages, just working from the back to the front...

After fabricating new back sections (after the stock pipe splits into 2) it sounds really meaty and grumbly, although it began to drone even at that moment. 2,000-2,300rpm would just send a massive vibration through the car, drone like hell and even induce the dash rattle. Which i NEVER had until then :S

So day 1 isnt looking so hot at the moment, but theres always day 2 :) keep ya posted, and i forgot my camera so ill get some pics hopefully.

i have had the same problem, droning in that rev range, got straight through redback mufflers,replaced centre res with 10 inch hot dog and 8 inch hotdog before the split at the back, ok when its cold but give it some stick up hills and warm the mufflers up its unbearable, and theres nearly no note at all 2500 and above,. going to try another glass packed oval muffler instead of the hotog up front, will let you know how that goes.

Always something I've been interested in doing to an Aurion, I'd love to see a LARGE centre muffler with just two hotdogs at the back. I think half the issue is there's so much pipe with nothing to stop some crazy reverb happening.

im thinking along the same lines,i will see what goes with a muffler up front and what sound i will get from the redbacks, if it is too quiet take redbacks off and run with straight pipe out back.

[SirNed]

OK I know this is an old topic but was wondering if there are any updates on the Exhaust mods?

[Tofuboi]

OK I know this is an old topic but was wondering if there are any updates on the Exhaust mods?

Yeah at the moment there isn't a whole lot going on. I'm more focused on some other things to my car at the moment so the exhaust stuff is on hold.

[Jap]

I'd like to see this thread kick off again, I'm all for playing around with exhaust systems lol.

I have a funny feeling I know what is causing your error codes to show, it would be interesting to check out this experimental system.

[00UCH]

I should have mine finished in 1-2 weeks with NO codes flashing at me :)

[SCOOTA44]

Its taken a while but here are photo's of the exhaust mod. everytime I look at it I think more about a twin system,Im sure it could be done if you could place 2 hi flow cats side by side. I should stop thinking, it cold get expensive !

[Jap]

Thanks for the update.

What is happening up near your headers? looks like a stock pipe disappears into a 2.25 or 2.5" pipe?

Also, keep the pipe diameter down, this helps reduce drone.

I've done some R&D on the 1GR and it is a hard engine to dull down.

Don't be greedy with diameters and you'll be set

[SCOOTA44]

Thanks for the update.

What is happening up near your headers? looks like a stock pipe disappears into a 2.25 or 2.5" pipe?

Also, keep the pipe diameter down, this helps reduce drone.

I've done some R&D on the 1GR and it is a hard engine to dull down.

Don't be greedy with diameters and you'll be set

[/quote That was the only bit I didn't like with the mod (the larger diameter) pipe, the only part I need to update is the collector, its too thin and you can hear a buzz, sounds like a leak. They removed the small cat from the rear header. Im thinking of trying to get another manifold to cat and set it up properly.

[Myxalplyx]

Thanks for the update.

What is happening up near your headers? looks like a stock pipe disappears into a 2.25 or 2.5" pipe?

I am wondering about this as well. You are referring to the part where the two headers join inot a single exhaust pipe right? The picture looks like it joins them smoothly. Really nice!

Outside of the header, piping sizes, cats and resonators, the only thing that may be worth changing is the mufflers themselves. If you remove the stock one, take a look at how the exhaust flows through it. If it appears that the exhaust flow is not a straight/direct flow, then change it out for a muffler that has a straight through flow. Just make sure the muffler itself is a decent size so that it actually does some muffling rather than making a lot of noise.

[Jap]

I am wondering about this as well. You are referring to the part where the two headers join inot a single exhaust pipe right? The picture looks like it joins them smoothly. Really nice!

Outside of the header, piping sizes, cats and resonators, the only thing that may be worth changing is the mufflers themselves. If you remove the stock one, take a look at how the exhaust flows through it. If it appears that the exhaust flow is not a straight/direct flow, then change it out for a muffler that has a straight through flow. Just make sure the muffler itself is a decent size so that it actually does some muffling rather than making a lot of noise.

No, I was referring to the part on the front header, where it looks like a stock pipe drops into a different section.

Looks like crap.

Cats also take a lot of harshness out of an exhaust note (especially if you're re-using stock ones) so keep that in mind when altering your system...

[SCOOTA44]

Thanks for the update.

What is happening up near your headers? looks like a stock pipe disappears into a 2.25 or 2.5" pipe?

I am wondering about this as well. You are referring to the part where the two headers join inot a single exhaust pipe right? The picture looks like it joins them smoothly. Really nice!

Outside of the header, piping sizes, cats and resonators, the only thing that may be worth changing is the mufflers themselves. If you remove the stock one, take a look at how the exhaust flows through it. If it appears that the exhaust flow is not a straight/direct flow, then change it out for a muffler that has a straight through flow. Just make sure the muffler itself is a decent size so that it actually does some muffling rather than making a lot of noise.

I actually went from a staight through to triple flow sports muffler, give a better note than the straight through ones and give a nice rumble at revs. In reference to the front header yes the stock pipe does go into a larger diameter piece, and the rear one is that size right up to the manifold down to the merge. As dicussed in earlier threads these "pressed cone" collectors are thinner than stock pipe, due to their shaping therefore prone to sound leakage (buzzing) this is why Im thinking of either getting another manifold to cat and start again or measure up spacing for 2 oval cats and twin pipes from there.