Question about PSI
DeeJayy
12-21-2006, 08:08 PM
How do you change it? Like I've heard or people that run different PSI's during the week and the weekends (ex. I run 12 PSI daily but 15 PSI on weekends) .. I know about turbo controllers and that good stuff but what I'm woundering is how it works
Thanks for the input
Thanks for the input
UncleBob
12-22-2006, 12:17 AM
all wastegate actuators (internal and external) work off of pressure vs spring tension. The spring will apply X force against the valve, and the boost reference will push past the spring tension at X.
You adjust your boost by changing the above mentioned parameters. The simplist way is with a boost controller. A simple device that you put inline between the boost reference and the waste gate. It will limit/bleed pressure that is getting to the actuator, "fooling" the actuator into thinking its seeing less boost than is actually in the intake.
Then you get into more complex setups, such as electronic wastegate actuators, CO2 acuated wastegates all usually involve computer controls that sense speed and/or gear you're in and adjust the boost levels accordingly.
For example, I use a dual stage boost controller. Its a 2 position "vacuum" solenoid. In one position (closed) it puts boost reference directly to the wastegate. In the other position (open) it redirects boost reference through a boost controller and changes my boost setting to whatever I have the boost controller set to. This way I can have 2 boost settings on the fly, with a touch of a switch.
Any time you play with raising the boost, you have to be careful that you don't go too high for your octane. In case this isn't obvious: increasing boost X psi very well might be the difference between your engine running well for a long time and it blowing up in a couple miles.
Seriously.
You adjust your boost by changing the above mentioned parameters. The simplist way is with a boost controller. A simple device that you put inline between the boost reference and the waste gate. It will limit/bleed pressure that is getting to the actuator, "fooling" the actuator into thinking its seeing less boost than is actually in the intake.
Then you get into more complex setups, such as electronic wastegate actuators, CO2 acuated wastegates all usually involve computer controls that sense speed and/or gear you're in and adjust the boost levels accordingly.
For example, I use a dual stage boost controller. Its a 2 position "vacuum" solenoid. In one position (closed) it puts boost reference directly to the wastegate. In the other position (open) it redirects boost reference through a boost controller and changes my boost setting to whatever I have the boost controller set to. This way I can have 2 boost settings on the fly, with a touch of a switch.
Any time you play with raising the boost, you have to be careful that you don't go too high for your octane. In case this isn't obvious: increasing boost X psi very well might be the difference between your engine running well for a long time and it blowing up in a couple miles.
Seriously.
DeeJayy
12-22-2006, 09:16 AM
Ok thanks .. I wasnt sure how it worked. Thanks for clearing it up
GreyGoose006
12-22-2006, 04:10 PM
really serious racers who use lots of boost pressure will usually limit boost (and therefore horsepower) in first and sometimes second gear.
if you are drag racing, this could be the difference between getting excessive wheelspin and not going anywhere, and getting a perfect launch.
if you are drag racing, this could be the difference between getting excessive wheelspin and not going anywhere, and getting a perfect launch.
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