vacuum/boost take off
Turbo Mini Forums

Hi,

i was wondering if the pipe i take the vacuum and boost from could be to small?

I blew a headgasket and found that my wastegate could not move freely. I fixed that:)
But when i was checking the waste gate when the engine was running i did not see any movement.
When i disconnected the hose from the manifold and blew some air in the hose the waste gate did move.

To make sure i plumed a extra gauge into the lines and when it's getting it's signal from the manifold nothing is happening, no boost to be seen on the gauge exept that the dump valve is working. So there is some boost but i can't see it on the gauge.

When i blew some air in the hose myself it was showing that on the gauge.

So does the point where you get put youre wastegate, dumpvalve and boostmeter have to be a certain size to work properly? Ans what size is the minimal

This how i have it at the moment......

Edited by paneermeel on 22nd May, 2011.

there is nothing wrong with a A-series that a turbo can't fix.

www.turbomini.nl

you'll need to connect that pipe for it to work!

try blowing down that take of to make sure its clear,

also suck on the pip your connecting to it to make sure the gauge moves.

On 22nd May, 2011 Joe C said:
you'll need to connect that pipe for it to work!

there is nothing wrong with a A-series that a turbo can't fix.

www.turbomini.nl

you'll never see boost until the engine is under load.

Is there a trick to get the same effect when standing nect to the car?

there is nothing wrong with a A-series that a turbo can't fix.

www.turbomini.nl

put it on a rolling road.

Jack the car up front, get someone to lightly touch the brakes while accelerating, and you could check it out at the same time.

Don't do it if you doesn't want to be killed though.

Edited by Utking on 22nd May, 2011.

I always use a seperate feed to the actuator, and generally from the other side of the butterfly (i.e. the plenum or the turbo).

It is important that the dumpvalve has at least a 4mm hose, bigger if possible. But the boost gauge and actuator are not important.

In fact, lots of us run 1mm or 1.5mm restrictors in the feed to the actuator to enable good boost control.

Fastest 998 mini in the world? 13.05 1/4 mile 106mph

[quote=wil_h,22nd May, 2011]I always use a seperate feed to the actuator, and generally from the other side of the butterfly (i.e. the plenum or the turbo).

quote]

I like this idea
Will be doing this when i get home.

there is nothing wrong with a A-series that a turbo can't fix.

www.turbomini.nl

Wil, can you expand on the idea of a restrictor to enable boost control,please ?.

Everything I knw came from robert.

But basically, you put a restrictor between the feed from the plenum/turbo 'snail' and the bleed valve (or boost controller).

This restricts the amount of air available to the actuator which means you have to bleed off less air to change the boost level.

It makes a bleed valve very sensitive. BUT, the downside is that you are prone to boost spikes. Because as boost builds the actuator does not quite have enough volume of air to keep up. The smaller the restriction the worse the spikes get. I found that 1.5mm was a decent componise.

My restrictor is an in-line connector filled with epoxy and drilled out.

Fastest 998 mini in the world? 13.05 1/4 mile 106mph

Most of what I know (not a lot) came from TM forum and Robert in particular.

If the restrictor makes the bleed valve so sensitive and spikes may occur, what is the advantage ?

I have found that upping the boost to a sensible level via different springs in the actuator and pre loading it and then using a bleed valve it is fairly easy to get the boost I want. Once I have done that I put a solenoid valve on the outlet from the bleed valve so that I can switch from low to higher boost on the fly. (Just like Robert !)

I used a 5psi actuator with 5mm of preload and couldn't bleed it out further than 9psi with no restrictor.

With a restrictor I could have what I wanted.

Yes a better actuator is the best solution, but a restrictor is super cheap.

It is pretty common for modern cars to have a restrictor in the line to the boost controller.

Fastest 998 mini in the world? 13.05 1/4 mile 106mph