How accurate is the dashboard OEM digital bar/number psi readout for turbo boost?

 

Not very accurate I'm told.

Regarding boost, I think I may have another hose that's coming loose. Previously I had an I/C loose hose and it made a rather noticable air rushing sound and of course the car was a bit slower on acceleration.

But at the moment, the car feels a little slower, and there is just a slight, different noise (like air, but hard to say). When I floor it, sometimes the boost guage stays pinned, and sometimes the boost guages fades after 4-5 seconds (either in overboost or regular). So, I'm not sure if I can rely on the boost guage to help me determine if I have a boost leak or not.

I'd just assume take it back to the dealer for them to check it out, but that's a 60 mile round trip (they pickup my car, so it's not my time, but miles on my car).

Anyhow, I know there were prior posts on boost loss, but I think the outcome was take to dealer and have them do a smoke test. Hoping there may be an easier way to diagnose at home.

 

Taylor, if your clamp has come off again, I'd recommend using these:

http://www.aircraftspruce.com/catalo...es/oetiker.php

 

Thanks. I'll have the shop get those if a clamp is loose.

As to not thread jack, what I think is relevant to the OP's post is whether the boost guage can accurately identify if there is a leak (by means of the guage dropping).

I think perhaps the OP's question may have been more regarding the absolute reading of the guage (e.g. 17psi is 17psi). If the guage is not accurate, is there a standard deviation that's been quantified? Although I'm pretty sure the boost guage is not sufficient for tuning purposes, perhaps with a small SD it's sufficient for knowing close to where the psi's are running.

So I think the jury is still out on that.

 

what is the highest psi on a turbo with sport chrono? with sport mode on and off? the reason why i ask is my car will display 15psi with sport mode off and 17 psi with it on, BUT the bar goes up to 18... Why have 18, but not be able to go up that high?

 

The speedo says 225.

Is your car stock? I only see 11-12psi with sports mode off 15 psi with it on. My car has a fabspeed exhaust.

 

What type of tune do you have?

 

Taylor,

i see you found your gt3...congrats...give us some info in another thread!

 

i swore i saw it before my tune, but i currently am running evomsit stg II. the major difference after the tune is the boost comes on much quicker and stays on all the way through.

so, anyone ever see 18psi on the gauge OR is it just there for looks?

 

I only saw a high of 15 before my tune and after the tune I am seeing 17 as tops in sport mode.

 

No tune (on a track, of course)

 

Totally stock, in sport mode my high is also 17psi, 15psi in normal.