Parnelli,

At normal cruising or very light throttle, the boost gauge will show 0.0 BAR (no boost). As you get into the throttle, the gauge will start recording higher boost levels... up to 0.8 BAR. This is about the maximum boost for a stock 993TT. Many guys have modified their cars for more boost, but the gauge will never show more tha 0.8 BAR... which is too bad; we all wish it would read up to 1.2 BAR or so.

 

I have a European 993 TT with the X50 option (factory 430 HP kit); the factory advises that for this engine spec., maximum turbo pressure is 0.9 bar. Yet I have never read more than 0.8 bar on the on-board computer. For the 450 HP Turbo S, maximum turbo pressure is 1.0 bar (I think), most likely the owners have not read more than 0.8 bar either.
BTW, if I remember correctly, the factory advises to read turbo pressure with either 4th or 5th gear engaged.

 

As said before the gauge will not display boost values above 0.8 bar - that's by design.

 

Thanks for the info guys. My car has felt correct, but the gauge had me slightly concerned. I am still trying to get accustomed to the quiet purring of my turbo vs. my normally aspirated 993's spirited growling.

I need to make a change in the turbo to give me the sound that matches the performance.

Cheers...

 

Mine goes to 11. When I need that extra push.

 

i find the turbo boost gauge on the display is a piece of crap. Mine has failed twice in the past 4 years. It often shows 0.2 bar even when the car is rolling at 5mph or at idle.
You need to put a real external boost guage on the car to get a real reading.
Yes, they are not designed to go above 0.8 bar.

 

John,

Let me know if you want to hear mine. Best mod I've made.

 

The guage will go a LOT higher than that. Back when I first joined Rennlist I, I freaked one day when I looked down and it was a like 1.5 (something like that).

I went straight to the dealer. They said "don't worry about it". Yeah right. They want an engine rebuild. That freaked me more.

I came straight here and someone suggested checking sensor connectors. The wiring harness recall had been done only a few months before. I got in there and checked everything. Whatever I wiggled made it go away. I've never seen it over 0.8 since then. It had never been over 0.8 in the first place.