New zaust being fitted Saturday !! **DONE**

Post Thu Dec 07, 2006 9:43 pm

After my R/R result, i wasnt too happy, but have since been ok and got my head round the impressive torque figure of 225lb.. but ive spoken to my local performance zaust centre (Torque exhausts) who have nearly garaunteed me an increase in both bhp and torque with a new 2.5" free flowing Vortex system... so confident that he is offering to contibute towards R/R mapping if no gains.!! After much discussion about the size, ive decided on 2.5" not to lose on any torque figures... so results to follow..

Post Thu Dec 07, 2006 10:08 pm

The best exhaust for a turbo is no exhaust so going really big at the exducer isn't a bad thing.

2 1/2" should be fine though, wait with bated breath

What's a Vortex system though?

Post Thu Dec 07, 2006 10:31 pm

who did you discuss with ,and what was reasoning in favour of 2.5?

3 inch -tubby to tail with a tombstone tail,for me

Post Thu Dec 07, 2006 10:38 pm

I had a 2.5" pipe on my car and it fitted perfect.Iv now lowered it 60mm and made a 3" system .I wish i had not bothered as it is only about 3" off the floor.

Post Thu Dec 07, 2006 10:39 pm

Turbo-Brown wrote:The best exhaust for a turbo is no exhaust so going really big at the exducer isn't a bad thing.

2 1/2" should be fine though, wait with bated breath

What's a Vortex system though?

vortex is a new kinda system with top reviews... they say it acts like a vacuum and draws the fumes out enabling them to escape alot quicker.. the reason behind the 2.5" was that i dont lose any of my torque..

Post Thu Dec 07, 2006 10:42 pm

e30cossie wrote:I had a 2.5" pipe on my car and it fitted perfect.Iv now lowered it 60mm and made a 3" system .I wish i had not bothered as it is only about 3" off the floor.

youve only lost .5 inch over the 2.5 system for ground clearance?

Post Thu Dec 07, 2006 10:57 pm

I know it is only .5 but the bends on 3" are a lot bigger and take up a lot more space. The downpipe took me about 4 hours to make.

Post Thu Dec 07, 2006 10:59 pm

e30cossie wrote:I know it is only .5 but the bends on 3" are a lot bigger and take up a lot more space. The downpipe took me about 4 hours to make.

tight past column,or was it a nice fit...

Post Thu Dec 07, 2006 11:05 pm

there is a stainless metal company near me and they sell 90 bends,45 bends and straight tube so i buy the bits i need and cut and weld. The downpipe was so tight in the end i cut out a small section and wealded a flat plate and all looked good in the end

Post Fri Dec 08, 2006 8:09 am

You shouldn't lose torque by fitting a giant exhaust to a turbocharged engine.

I'm deeply sceptical about these things that claim to create a vacuum and the like, have you got any details on how it's supposed to work Erel?

Typically they'll tell you what they think it does, not how it works (or doesn't)

Post Fri Dec 08, 2006 9:04 am

Erel,

EVERY exhaust 'specialist' I went too said 2.5 inch was as big as I needed, best allrounder etc.

I ended up with a 3inch straight through, turbo to tailpipe!

As Alex said, turbo needs no backpressure at all, so larger the better.

You ask the Swedes on PPF and they all run atleast 3 inch, some 4 & 5 inch downpipes into 3 or 4 inch systems.

Gotta say 3 inch is a PITA to fit around the steering but it does go with some adjustment

This time BIGGER is BETTER!

Post Fri Dec 08, 2006 9:10 am

"3 end to end,
donÃ‚´t waste your time with a in the meantime "2.5

Post Fri Dec 08, 2006 9:33 am

I've already stated the case for the 3" guys.

2.5 isn't worth the investment imho. time or Ã‚£Ã‚£

Post Fri Dec 08, 2006 1:19 pm

I understand and appreciate your replies fella's.. ive got till 2moro to change my mind, but the only reasons ive opted for the 2.5" is

1. I thought i would lose torque by going 3". ? Is this not true then??
2. I believe sierra cossy's have a 2.5" systems and they all lash out over 300bhp!

So rather than doing 2.5", would it be ok to go 3" from downpipe back...?

Turbo-Brown, as for how it works, errm, he sold it to me good didnt he, ? but i did a search on VORTEX exhaust system and it found a few good reviews..

Post Fri Dec 08, 2006 1:20 pm

dude id go with Ant's advice mate

Post Fri Dec 08, 2006 1:47 pm

Fair enough, just don't see how you can modify a pipe to generate a vacuum myself.

Anyway, just to clear up a couple of points:

No engine needs backpressure to make power. You see the term bandied about a lot but people don't seem to understand what's useful as backpressure and what's not.

Keeping gas speeds high in the manifolds and to a lesser extent in the system can promote scavenging in the cylinders and thereby lead to better cylinder filling. To keep the gas speed high, the pipes mustn't be too large and the trade off is a little more back pressure than no pipe would give, but an overall increase in power.

Now, take a manifold and weld a washer into each runner and you'll get massive back pressure but obviously massively decrease power etc.

With a turbocharged engine, you ideally want to keep the pulses as seperate as possible and as hot as possible up until they reach the turbo, but after that, there's pretty much nothing to be gained by further restricting their flow. You just wanna get rid of them through whatever drain-pipe you can fit in

Post Fri Dec 08, 2006 2:04 pm

So will i not lose bottom end torque by going 3" as opposed to 2.5"

Post Fri Dec 08, 2006 2:08 pm

Shouldn't do, you might even see boost sooner on in the rev range and more power for the same boost

Post Fri Dec 08, 2006 2:20 pm

sounds good

Post Sat Dec 09, 2006 10:43 am

blingsta wrote:So will i not lose bottom end torque by going 3" as opposed to 2.5"

start it at 2.5" and mid system increase it to 3"

a lot of jap cars have huge exhuast systems from the turbo back and they loose lots of torque, i might add this is mainly on big power skylines.

when fitted with a system with a gradual increase in diameter extra power is found more low end torque, and no detrimental effects to over all power

on dips cossie, after a rolling road session and after driving it we felt it was feeling a bit restriced, the car was running 2.5 all the way thru and pushing about 20psi and made 380bhp and similar tourque figuer

now, its been changed to a 3" after the centre box to the tail pipe and is has made on hell of a difference, much smoother, more grunt. unfortunatly no new power figures but i'm sure it has increased

the theory with turbo cars is that you want minmal back pressure, but with hot gasses expanding and rushing thru the system, the system bore needs to expand to accomodate the flow

Post Sat Dec 09, 2006 1:36 pm

A exhaust on a turbo car canÃ‚´t scavenge , belive me the turbo at 100,000rpm is doing alot more scevenging then
any exhaust header ever could, why do you think you have more power at 0psi then before?
ItÃ‚´s not because air is beeing assisted in , but assisted out much like real good headers would do.

turbo exhaust is for flowing the exhaust out from under the car and nothing else, you will not loose any spool, rather gain it by having no backpressure holding up the air flow ,
and donÃ‚´t buy that vortec vacuum thing , just get some simple mufflers to keep the noise down, if the noise is to high add some more, for instance put one where the cat should be, if that is good enough, but a pipe all the way back, if not add another one inline with this one, if thats not good enough, add another one in the back and call it a day,

the turbo is the main muffler in the system

Post Sat Dec 09, 2006 3:06 pm

Kos and Gunni, sorry guys but your comments/views were a little too late as new zaust has been fitted, i decided to go 2.5" all the way! A noticeable difference was noticed straight away! believe it or not car seems to be faster both low and high up in the rev range, and as for sound, It's well throaty !!!..

Gunni, why did you say "dont buy that vortec vacuum thing"? have you had any experiences with it mate?

From what i can see, this thing actually works, you can actually hear a swirling type noise from the box under load.!! sounds great.

.. All thats left is a power run on R/R on Monday to check if there has been any improvements, i'll be surprised if there isnt.

Post Sat Dec 09, 2006 5:32 pm

Cool, what does a swirling noise sound like? The product sounds like good marketing to me(coming from someone doing a degree in it

)

I'd also be suprised if there wasn't an increase in power, just there would have been more of an increase with 3inch i feel. As long as you are enjoying it

Post Sat Dec 09, 2006 7:05 pm

thew swirl noise is more than likely to be the sound of the turbine spinning @ idle, Blingsta had a two box OE sty;e system originally to keep cost down ( originally ) the new setup is single box, so the change in sound will be a similar effect to a one boxed RS turbo , with the resultant low rpm turbo growl

Erel, no WOT on that dyno unless the WB02 is on and being closely monitored ..... I'd suggest a full slow run up 1 k 2k 3k 4k etc, rather than the usual lead foot from idle and see what happens style.

get the laptop hooked up too, and datalog the run/s, connect, click Alt L and choose a filename.

Post Sat Dec 09, 2006 7:26 pm

Ant wrote:thew swirl noise is more than likely to be the sound of the turbine spinning @ idle, Blingsta had a two box OE sty;e system originally to keep cost down ( originally ) the new setup is single box, so the change in sound will be a similar effect to a one boxed RS turbo , with the resultant low rpm turbo growl

Erel, no WOT on that dyno unless the WB02 is on and being closely monitored ..... I'd suggest a full slow run up 1 k 2k 3k 4k etc, rather than the usual lead foot from idle and see what happens style.

get the laptop hooked up too, and datalog the run/s, connect, click Alt L and choose a filename.

Ant, cheers for advice fella, i was gonna go for power run on Monday, but as i said to you before, they dont use the wideband on just the power runs!! could this be dangerous for me mate?? and in regards to getting the laptop hooked up! U know im clueless mate.

.. what should i do matey, not go b4 i see ya?

Post Sat Dec 09, 2006 7:28 pm

did you remember to get an 02 sensor boss fitted M8 ??

It was on the list of goals when we disussed the zaust last time around.

Post Sat Dec 09, 2006 7:34 pm

Naah, didnt ask as they done it from end of downpipe back.. i can always pop back on Monday though!

Post Sat Dec 09, 2006 7:41 pm

Oh Ant.. the swirl noise i was talking about mate, is at load rather than at idle and doest sound like turbo..its coming from the rear wher the new box is?

Post Sat Dec 09, 2006 7:44 pm

Video clip required

Post Sat Dec 09, 2006 8:50 pm

.. Dude, im useless on computers !!! you can maybe do the honours next time we link.

.. p.s sent ya pm

Post Sun Dec 10, 2006 2:05 am

That sound is probably the wastegate beeing heard or turbine spinning,
sounds to me your exhaust is well open trough?

the vortex thing canÃ‚´t work on a turbo car, the function of any scavengin stops at the turbo, unless in some major high pressure systems,

With the new exhaust IÃ‚´m sure your EGTÃ‚´s have dropped nicely and the exhaust reversion back into the engine has either stopped or gotten alot better, that is the reason for the new found power

IÃ‚´m sure you want to get to a dyno as soon as possible now, to see how much the exhaust made in power,

IÃ‚´m happy it worked out so well,

Post Sun Dec 10, 2006 2:10 am

cheers buddy.

Post Sun Dec 10, 2006 12:13 pm

blingsta wrote:Kos and Gunni, sorry guys but your comments/views were a little too late as new zaust has been fitted, i decided to go 2.5" all the way! A noticeable difference was noticed straight away! believe it or not car seems to be faster both low and high up in the rev range, and as for sound, It's well throaty !!!..

seems very promising mate now get it on that Dyno because you've probably lifted some restriction as you've noticed the difference. See aint so bad now!