[encountar]

Hey guys, maybe martin has some specific info on this

[Shambles]

I watched the vid and still don't know what a dose is  

[eye30]

That sounded rough as 'ell.

[Martin]

I think you will find that the 'Dose' noise you refer to there isnt being generated by the Captiva    

[encountar]

Eh, wasnt sure if it was or not. still would be cool as [censored] factor for a day or two

[Martin]

Dude if you want [censored] factor, an i30 is probably the wrong kind of car to have bought........  

[encountar]

Na, no need for another car for [censored] factor
i have my harley in the shed, its loud enough for everyone to think im a tosspot  

[Martin]

you gotta start at the bottom and work your way up with motorbikes, harley being the starting point  

This we will agree on

[pedro]

The sound you can hear is air reverbarating back through the turbo. Cars with no blow off valve or incorrectly set up ones do that. As pressure builds the engine uses it, when the throttle is closed it has no where to go so it fights against the turbo wheel and reverbs back and forth creating the whoop whoop whoop sound.    

[LuciferDarklord]

Yeah compressor surge.  Why people like this sound is beyond me, and the name - dose?  Knob Jockeys if you ask me.....

[Lakes]

The sound you can hear is air reverbarating back through the turbo. Cars with no blow off valve or incorrectly set up ones do that. As pressure builds the engine uses it, when the throttle is closed it has no where to go so it fights against the turbo wheel and reverbs back and forth creating the whoop whoop whoop sound.    

Pedro, a decade or so back, a friend of mine's son had a mazda?? AWD 1.6 Turbo think 323? he took the wast gate out to allow more boost, i was driving it then backed off to take a corner and it started to jurk bad, he told me was cause he closed the wast gate that was before i ever saw those fart valves used.
i think what Eye and the boys feel with there flat spot is a mild virsion of this as i have felt that when i first got my car, just i drive differently now and don't feel that but thought thats same only milder, and latter found the turbo in i30 does not use a waist gate.

[pedro]

He wouldnt hav taken the waste gate out as that would have lowered his boost, closing the wastgate directs airflow to the turbine wheel to create more boost.
Your right that the turbos on the i30 are different as they are a variable vane style. Very interesting turbo as the boost curve and pressure too i believe is regulated by mulitiple vanes that direct gas flow to the turbine at different angles to change boost and efficiency where as a conventional turbo has a waste gate flap that completly by passes the turbine as boost comes to its preset limit.
Id be interested to see how Martin regulates and hences rises the boost pressure with his upgrade. Ive have been reading articles from martin in different media for yrs now and he really is at the forfront of the latest technology and development in engines. Once my warranty is up ill be calling him the next day.

[Lakes]

He wouldnt hav taken the waste gate out as that would have lowered his boost, closing the wastgate directs airflow to the turbine wheel to create more boost.
Your right that the turbos on the i30 are different as they are a variable vane style. Very interesting turbo as the boost curve and pressure too i believe is regulated by mulitiple vanes that direct gas flow to the turbine at different angles to change boost and efficiency where as a conventional turbo has a waste gate flap that completly by passes the turbine as boost comes to its preset limit.
Id be interested to see how Martin regulates and hences rises the boost pressure with his upgrade. Ive have been reading articles from martin in different media for yrs now and he really is at the forfront of the latest technology and development in engines. Once my warranty is up ill be calling him the next day.

Pedro, i've never been very interested in turbo's, but have watch them dyno motors useing them, my friends son was playing around with the turbo, the waist gate has springs, he was playing with the springs.
when you up the boost as the revs go up unless you have a large enough turbo, the turbo becomes a restriction so they get the excess exhaust out opening the waist gate.
the i30 turbo would be a very low end turbo as its very small, someone here had a good moving cut in half model of the turbo the i30 use has an outside band with variable vanes they are varied useing vacume, then there is a conventional screw type turbine in the center. since getting the scanGauge11 can see they run a lot of boost, if you have the motor in 5th and have the rev @ 1,900 and take a hill keeping it at that rev you see the turbo boost pressure go up to 22psi i've seen it spike as high as 30psi but i try to keep it around 15psi for economy.

[mtpleb]

Pedro is 100% correct in saying "He wouldnt hav taken the waste gate out as that would have lowered his boost, closing the wastgate directs airflow to the turbine wheel to create more boost."

The inbuilt wastegate when removed will result in almost no boost at all depending on the wastegate port size.

 The wastegate's main function is to regulate boost so it doesn't rise above a certain level as dictated by the spring. When that 'certain level' of boost begins to overpower the spring, the wastegate begins to open to vent excess exhaust gas that would otherwise spin the turbo faster and create more boost.
 So it is more about boost and turbo rpm control than it is about the turbo becoming a restriction.
The springs are in a sealed canister and are generally not changed to alter boost levels, the correct way to easily increase boost is to bleed off    or waste a tiny bit of boost before it reaches the wastegate spring.

This is done with an adjustable valve in the 'gate feed line , the 'gate spring will still see for example a mild 6psi and begin to open, however the turbo could now be pumping 10psi + because 4psi is being diverted away from the 'gate spring via the valve in its feed line, effectively 'tricking' the wastegate into opening later so a higher boost is achieved.
A very nasty way of increasing boost is to limit the amount that the wastegate opens usualy with a cut & welded (shortened) actuator rod.
This will give more boost but also generates more heat.

Pedro said "Ive have been reading articles from martin in different media for yrs now and he really is at the forfront of the latest technology and development in engines."
I could not agree more, anyone who questions his credentials when it comes to the turbo/efi/tuning scene must have been living in a cave for the last 15yrs or so.
cheers.

[i30cruzer]

Mtpleb, i totally agree with you about martin....top bloke.

but what are your credentials? Are you a mechanic? or are you just another guy who thinks hes a professional? No offence  

and as for you lakes, well knowing a guy that knew a guy that had a cousin that did something, mate, leave it to the pros to talk about it and id think twice bout challenging martin!!

[mtpleb]

Hey cruzer, no offence taken
No, I'm not a pro' nor do I consider myself an expert, i have however turbocharged and built/tuned engines in the past with up to 150% power gains and won a dyno comp in the 'most hp per cu in' catergory, so I do have more than a fair idea.

My points on turbo and wastegate operation are not just my opinion, they are simple facts which anyone can research, credentials not neccessary.
cheers.

[i30cruzer]

Ok, so you just google things then post them?
when did you win the comp?, ive won a few in my time....what kind of engine, turbo were you using? anything that could be related to the technology avaliave now? or we talking back in 80/90's?

[mtpleb]

cruzer, I posted simple established facts on the operation of a turbo's wastegate, which I have learned from hands on experience.
Experience that is chicken piss to the likes of Martin I think you will agree.
Are you saying it is wrong?
Are you saying I am a liar and I just googled it?
I simply posted in reply to Lake's somewhat incorrect statements on the subject and unlike you I refrained from bagging the guy.
Now your are starting on me, I have no claims to fame, I have some experience as stated but nothing to get excited about.
I have nothing to prove to you or anybody else so I will not indulge you in your sh3t stirring.
cheers

[i30cruzer]

cruzer, I posted simple established facts on the operation of a turbo's wastegate, which I have learned from hands on experience.
Experience that is chicken piss to the likes of Martin I think you will agree.
Are you saying it is wrong?
Are you saying I am a liar and I just googled it?
I simply posted in reply to Lake's somewhat incorrect statements on the subject and unlike you I refrained from bagging the guy.
Now your are starting on me, I have no claims to fame, I have some experience as stated but nothing to get excited about.
I have nothing to prove to you or anybody else so I will not indulge you in your sh3t stirring.
cheers

Hey hey, Mtpleb, relax, im not having a go at you, i was just wondering, coz there are a lot of people out there that just google, copy and paste....i now know that that is not you.....but i did ask what kind of cars you have modified? Also do you own a I30 yourself? if so what do you have.....as for martin, well he is in a leauge of his own.....top bloke and will forget more things than we will ever know!!!!

[Dazzler]

Guys...

Lets all agree to disagree... These sort of discussions tend to get out of hand (and aren't necessary)

No one is on here to earn stripes. Lakes for example isn't a big noter and has had a lot of hands on experience.. (and lots of mates)

We've already lost a member who got given one serve to many so if you can't say something nice , don't say anything at all.

Thanks

[Lakes]

Mtpleb, i totally agree with you about martin....top bloke.

but what are your credentials? Are you a mechanic? or are you just another guy who thinks hes a professional? No offence  

[Dazzler]

Hey Lakes,
Your spelling is "interesting" to say the least but we get the message....

[i30cruzer]

Guys the forum is about disscussions and opinions, i am mearly asking mtpleb what his credentials are....and i got the answer...none....and what cars the guy/girl has worked on and alledged to have won comps with it....and telling lakes that a friend of a friend of a cousin of his isnt enough to challenge certin people on this site.....

thats all

cheers

[Lakes]

Mtpleb, i totally agree with you about martin....top bloke.

but what are your credentials? Are you a mechanic? or are you just another guy who thinks hes a professional? No offence  

[i30cruzer]

whatev floats your boat lakes.....if thats what your into then maby you on wrong forum....i have papers to inregards to racing....but hey, like i said, maby you on wrong forum

[Lakes]

i30cruiser, i'm in to everything m8.
what about you?
bit shy on info.

[i30cruzer]

shy???? yeah right mate....

what ya wanna know......

[Zhangster]

view my comment on you tube... from zhangster1979