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Onefast99gsx
08-01-2005, 08:56 PM
Does the outside air temp and whether it's humid out have a direct impact on the amount of boost you build? The reason i ask is because the other day my MBC was set about about 22psi. The following day i cranked it over a 1/2 turn and tested the car and i wasn't building any more boost. Sunday was much hotter than Sat.

Thanks!
JET
08-01-2005, 09:34 PM
What is your setup? Especially the turbo/wastegate.
Onefast99gsx
08-01-2005, 09:37 PM
PTE 50trim, cut divider, internal wastegate(the newer internal gates). Hallman MBC,

Thanks.
JET
08-01-2005, 09:39 PM
I am guessing your actuator isn't adjusted properly and the wastegate is blowing open. Either that or your MBC is sticking. You can clean it if it is older it may have carbon in it.
Onefast99gsx
08-01-2005, 09:45 PM
I'll check both. Since i have 2 slimline fans the actuator is easy to get to. I'll loosen the actuator arm up, hold the flapper shut with one hand and retighten the 2 nuts with the other hand.

thanks much...
JET
08-01-2005, 11:14 PM
Actually you will want to take the arm off the wastegate and extend the arm. Adjust it until it takes a little pressure to get the arm back on.
Jacek
08-02-2005, 05:22 PM
In regards to the question, the air temp and air pressure have no effect on how much boost you build. For that is all with the boost controller spring compression.
niterydr
08-02-2005, 07:11 PM
In regards to the question, the air temp and air pressure have no effect on how much boost you build. For that is all with the boost controller spring compression.
Wrong.
Air temp can have a direct effect on how much 'boost' you can build. If your near the end of your efficency range, you can 'pin' what you can build for boost. (aka can't come up with the boost). Also if your tapped for your boost controller at your compressor cover, that'll change with weather conditions. Where is the boost controller tapped in at?
A boost controller is an item used for increasing demand on top of what the wastegate provides, pending how its hooked up. The boost controller can be influenced by outside temperature/pressure, and other motor/efficiency options, it just comes down to the setup most of the time.
JET
08-02-2005, 09:18 PM
Swanny is correct. Usually you will see a small change though. I have seen a max change of 2 psi in a car depending on the weather.
Jacek
08-02-2005, 09:22 PM
I apoligize, my text book did not go into the detail of efficiency. I guess I'm gonna call it a bad book. :)