Waste gate chatter?

Started by grigglet33, September 07, 2004, 02:33:15 PM

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grigglet33

Hi guys, i am new to Rx7\'s but i have always wandered how you get the waste gate chatter sound instead of the normal dump valve noise associated with most turbo cars? thanks

Fish

On and RX-7 you will need to swap from stock twins to a nice big single turbo.

Fish

Shaq

that sound is your turbos stalling not good imo,
but if you have some filters and block off a few pipes you can get that sound.

but i would not recommend it

shaQ
12.7 on stock twins @ 1 bar (i reckon i can do better!)

20B_boy

QuoteOriginally posted by grigglet33
i am new to Rx7\'s but i have always wandered how you get the waste gate chatter sound instead of the normal dump valve noise associated with most turbo cars?
They are 2 different noises which are not dependant on each other. The BOV goes \'whoosh\', the \'chatter\' is the sound from some types of external wastegate that you have to run when you convert from the stock twin turbos to a larger single turbo setup...

Stock turbos = no chatter.
R.

Fish

Thats unless you are running either a rally car or a turbo that can handle being stalled.

Rally cars run without a wastegate, thus where the chatter comes from. But they have a budget for a new turbo at every stage.

A turbo that can handle being stalled on a regular basis are the Mitsi. TD range. ;)

Fish

antnicuk

oh good,  i have a huge Mitsi TD08 to go on my project 1st gen 13 b, once i sell my FD i will be on it!!!!
400 BHP - 650 KG\'s = 616 BHP Per Ton of Rotary Power

That\'s the way to do it! :Thumbsup!


MONSTER

Why would you want to stall the turbo, as I was always led to beleive you maintain the performance levels by keeping it spinning, surely stalling it would mean lag/spool up time being added to every major gear change or when backing off the throttle?:confused:


Steve

Shaq

^
my exact thought s
:confused:


shaQ
12.7 on stock twins @ 1 bar (i reckon i can do better!)

Fish

Its a noise thing. ;)

Once you\'ve done it, you want it all that little bit more. :D

Fish

zevans

QuoteOriginally posted by Fish

Rally cars run without a wastegate, thus where the chatter comes from. But they have a budget for a new turbo at every stage.

A turbo that can handle being stalled on a regular basis are the Mitsi. TD range. ;)

Fish

Rally cars have an external wastegate - ie a seperate bit of trickery after the tub in the boost circuit - rather than the wastegate being built into the turbo housing. That\'s why they\'re noisier - the gate\'s not buried in the middle of the engine bay somewhere...

They still have a wastegate! Otherwise, there\'s absolutely no way of controlling boost levels - it would build until something went bang. Be nice to be running 10 bar for a fraction of a second, but... :D (Actually the turbo would probably choke on its own boost way before that level and you\'d just end up with ridiculous intake temps and no power and lots of det.)

Even if you have a turbo that doesn\'t mind continuous stalling,you\'re introducing lag every time it stalls, so it hardly helps performance or response.

Recircs give better performance than BOVs unless you\'re flowing stupid amounts of air anyway...

Anyway, NA is the way forward as any fule no. :P

scooby_si


Fish

Wastegates are one way of controlling boost, another is air injectors. Ford have been using these for years. The ECU also controls the amount of boost that a car runs.

The apexi doesnt do it that well, but when you start looking at the money levels of WRC/proper rallying you look at stuff like Motec and Pectel to name just two.

I was running a held 1.8 BAR of boost on my old cortina, using a stock 2 BAR map sensor and a Motec M48 Pro to control the boost. I never had one instance of overboost with it.

As for the high boost levels, this is not a problem with engines that are properly mapped on bench dynos, by people who really know what they are doing.

Fish

20B_boy

QuoteOriginally posted by Fish
As for the high boost levels, this is not a problem with engines that are properly mapped on bench dynos, by people who really know what they are doing.

Fish
Talking of which, what boost r u going to b running then Danny? You given up on mapping on an engine dyno, right?
R.

Fish

Yeap, guess I will be back on the M1. ;)

So if you hear a loud noise late at night on that road, dont worry I\'ll be past you before you know it. :D

Fish

PS. High boost levels will not be run!

20B_boy

Thankfully a long way from my manner :D

Be careful dude.
R.