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Re: Boost Control

Brenden_R33

By Brenden_R33,
in General Automotive Discussion

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slamm Rising Star

slamm

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Posted

Yeah, same as above: gauge reads in 100mmHg increments up to 700. Given 760mmHg is about 1 bar (or 14.7 psi), half scale deflection (300-400mmHg) is about 7 psi which is wgat it should be.

Stolen from another post but you should be able to do the sums to get it to 10 to 12 psi.

edit. What the phuck is happening with the time here. these boards are haunted i tells ya. pirate ghosts. or ghost pirates. its actualy 12 22 pm the 4th of feb right now.

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Brenden_R33 Newbie

Brenden_R33

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Apologies for the ridiculous 'newbie' type question, but I'm a bit of a novice when it comes to most things mechanical (although i'm learning...slowly).

To cut a long story short, I did a bit of research and recently purchased and installed a larger FMIC on my car. Following on from that, I'd now like to run a little more boost to get some additional performance from the car and from what I've read on the forums, it seems like 10-12psi is relatively safe on the standard turbo. I do have a bleed valve installed on the car, although I believe it's currently only running standard boost due to the fact that the std boost gauge (which I know is a different unit of measure to psi) only goes up to around half way (i.e 3.5) when I use full throttle, which i've been told is pretty much indicative standard boost (i.e 6-7psi).

So this leads me to my few questions (and yes, I've done a search but couldn't find exact answers to my particular questions...probably because they're a little too basic for most people on here lol)...

Firstly, is adjusting the boost level as simple as just adjusting the bleed valve itself (which I believe it is)?

Secondly, is there any way in which I can tell what level of boost I've set the bleed valve to while I'm actually adjusting it? Or is it really just a matter of adjusting it, then taking the car for a drive to determine how much the boost has been adjusted (i.e trial and error).

Thirdly, how can I work out what level of boost i'm running (in psi) off the standard gauge? Or should I really invest in a new aftermarket boost gauge before adjusting the boost?

And lastly, should I really get someone else who knows what they're doing to do this for me instead? I'm keen to try and learn how to do these things myself (becuase it gives me a better idea of how everything works), although I really want to make sure that it's done properly and that I don't do any damage to the car.

Appreciate the help...

Cheers :)

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Brackez Contributor

Brackez

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The stock boost gauge should show if you have an effective boost increase, but as already mentioned with the small range of movement of the needle your ability to quickly and accurately read it at the engine/road speed required to make max boost is the limiting factor. I've only got stock boost & gauge and to be honest I hardly ever look at the gauge cause it's too small. Drove a Supra with an aftermarket one, much easier to read being larger and in a better position.

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