i have no boost controler at the moment and just messing around trying to get my car to idle right and run but i went out into the street to see how it drives and i did a couple of 1st gear pulls but not at WOT and i watched the boost on the stock gauge . but in 1st it goes way over, my question is high will the boost go with just a vac line running from the waste gate to the turbo?

 

Boost controllers cannot lower boost past what the wastegate will naturally achieve. So whatever your boost is without the controller, that will be the minimum boost with the controller.

Looks like you don't have a ported wastegate in your sig. Also no mention of intake or exhaust mods. If the intake and exhuast are still stock, don't worry. But if you have modded the intake/exhaust, worry. You need to get a proper boost gauge. And port the wastegate!

 

in his sig it says stripped emmissions im guessing he has open exhaust at the very least

 

i was crusing around on a open 3in dp and i do have a TID mod

 

it was only 1st gear pull so i couldnt imagine the waste gate has much time to open for that much amount of boost. the only reason i ask is because i did it then my car started running like **** then i turned it off and now it whont start back up, im pretty sure i didnt blow the engine because i do have fuel mods

 

my car with a ported wastegate if I take the MBC off will boost 5PSI and hold

 

it's not only about fuel you have to factor other things in such as timing. Also still on TMIC?

 

The stock wastegate is fully open around 5-6psi.

With a selfported S5 hotside I would see a 1psi creep but never higher.

Unported I would get up to 11+psi via creep but that's in higher gears.

Usually you do not have enough load to get a **** load of psi in 1st. 3rd is where I really see psi come in full steam.

You said your cars running crappy now and your boosting higher?
If so,I bet you blew the vac line to the wastegate actuator. Thus causing a vac leak and the wastegate will now never see psi so it doesn't open. Which causes you to over boost.

I had it happen to me and I hit 15psi by accident one night.

 

Get an aftermarket boost gauge.
This is no excuse, as even "cheap" ones are like $20 - $30 brand new.


-Ted

 

is your wastegate even working?
if you arent flooring it in 1st gear... it really shouldnt boost high....

 

Fuel cut is at 8.5 I think, and like Digi7ech said the stock gate opens at 5 or so. Also like aaron cake said you can't lower pressure below your wastegate's/acuator's preset level.

 

I second that ... esp considering what else he as done to the car...almost hard to believe there is no boost gauge.

 

in time, im not pushing the car untill i get a gauge and boost controler

 

you don't need a boost controller unless you want to turn the boost up. Port the wastegate, THEN get a boost controller if you want to raise it a few psi.

 

you also have to port your wastegate as so many people have told you....just getting gauges and controllers wont fix it. there is a physical limit to the amount of air your wastegate can let out. you need your wastegate opened up so it will let more air out quicker, reducing creep...and then you can use an MBC to bring it back up to where you want it once you have the proper upgrades.

 

haha sorry...i didnt refresh...and posted before i read the guy above me...basically the same answer...

 

im not saying i want to raise my boost. i just dont have one to lower it down at all

 

thats what everyone is saying. port your wastegate and you will not be able to achieve anything past 5psi. Then once you have your boost undercontrol then get a boost controller and turn the boost up safely.

 

read about how a turbo works, and how a wastegate works...the might clear things up a bit

 

a ported wastegate enables you to control your boost as opposed to letting it do whatever the hell it wants. when you port the wastegate your boost will STAY LOW.. but when you add a boost controller you can raise it and have it stay more consistent.... instead of the napolean "i do what i want GOSH" treatment

 

you guys told me verything i alreayd know

 

well...what dont you know? someone here can probably answer it...

 

Then why do you keep saying you need a boost controller??????

You installing a boost controller would have the same effect as setting a piston on your dash.

 

ok,, i'll tell you what everyone else is trying to tell you, but possibly in easy terms to understand

first of all, a boost controller only delays the opening of a wastegate.
so delaying your wastegate will only make you run more boost.

the FIRST thing you need to do is port the wastegate. and it needs to be larger than you might think, the bigger the better.
other than putting your stock crap back on, this is the ONLY way to lower boost/reduce boost creep.

if you port it large enough, you'll be back to the 5.5-6psi all the way to redline. if you want to run more than 6psi, only then would you need to buy a boost controller.

and to answer your original question, in 4th and 5th gears i would hit 20psi. but my 1st gear pulls only made it to about 13-15psi. i had a streetported S4 with TID and 3" turbo back exhaust. stock timing, stock TMIC, stock injectors but i did have a walbro 255. i havea video of my boost gauge that shows it.