drive pressure
- Thread starter 06dmax
- Start date
I run 60 psi of boost and see 75psi to 80 of drive pressure. Thats the race tune and i think i might a have a minor minor boost leak driving the pressure up. On all my other tunes its about 1to1 maybe a little more. 1to1 is really hard to get
Mines close to 1:1, during aggressive spool up I see DP up maybe 10-15# over boost. just briefly though. If I accelerate at 50-75% throttle it stays very close to 1:1.
Waiting on a new amp box for my pyrometer before I fool around much. Just trying to remember what I saw when it was tuned.
I assume you're running the 475 as a single?
Waiting on a new amp box for my pyrometer before I fool around much. Just trying to remember what I saw when it was tuned.
I assume you're running the 475 as a single?
Yeah I'm sure youre right. I installed the DP gauge because I read that one guy found he was running 3:1 !
I have found there isn't a ton of numbers out there for DP. Furthermore, many times people don't specify at what point they see 1:1 or 2:1 or whatever. Is it during spool up or once peak boost is achieved?
Fingers, when would you be most interested in the DP?
Tip in pressures as the turbo tries to build boost is a big deal besides the obvious max output numbers.
On VVTs, it is worth taking out some max vane angle on tip in if they are exceeding 3 times demanded boost or if they exceed about 90 PSI at any time.
On waste gated turbos, a sharp increase in drive pressure usually indicates you have hit the wall for what the turbo can produce.
VVTs will usually run 1.75:1 to 1.25:1 steady state with high tip in pressures till they hit the wall.
I have never personally seen a 1:1 regular turbo. In their operating range, I've usually seen 1.25:1 on a good performer.
On VVTs, it is worth taking out some max vane angle on tip in if they are exceeding 3 times demanded boost or if they exceed about 90 PSI at any time.
On waste gated turbos, a sharp increase in drive pressure usually indicates you have hit the wall for what the turbo can produce.
VVTs will usually run 1.75:1 to 1.25:1 steady state with high tip in pressures till they hit the wall.
I have never personally seen a 1:1 regular turbo. In their operating range, I've usually seen 1.25:1 on a good performer.
I saw 75 at around 30 psi on stock lbz. Im sure I'm seeing well over 100 with this lly stocker pushing 38 psi boost.
Well Y bridge would mean you're seeing what boost the ybride is seeing (probably just a tiny smidge more then what the manifolds are seeing) and I'm seeing what the turbo is producting before loosing some due to the intercooler and possible pipinf restrictions yada yada.
The close you can get to the compressor housing the better the reading will be as far as having a accurate drive/boost comparison. Same goes for where you have the drive port located.
The close you can get to the compressor housing the better the reading will be as far as having a accurate drive/boost comparison. Same goes for where you have the drive port located.
I want to know how much the engine is seeing. Imo the amount of air entering the engine is more important for boost/drive then how much is coming out of the turbo.
