chinoflyer

iTrader: (1)

hey people

I got a question. I am awared that in the winter or colder weather, our car boost a little higher, But how much is a little? I was driving my car today, and the outside temp is about 65 degrees. My boost patten was 12-15-???? (I let off when I saw my boost gauge went up that far).
Last time I test the boost I get 12-10-10. It was in the 80's (outside temp).

I have the home depot boost controller, it has been great for the pass 6 months. and I have not been messing with it since I dial it in at 12-10-10. I guess I will try to play with the controller and see if I can get it under control.

BTW, my mods are intake, downpipe, and catback. (boost related wise)

My post seem confusing, let me restate my question,

1) How much difference are your summer and winter boost (please state your outside temp)?
2) How do you adjust to this increase in boost? Or is it something that i need to be concern about?

thank you for your comment

chino

BobfisH

temprature doesnt make a huge difference to boost pressure, as 10psi of boost is 10psi of boost whatever and thats what the wastegate is set to open at. The extra speed from cold weather comes from extra density in the air, I.e more molecules of air per unit of volume due to denser air.

If your getting boost spikes, check your boost controller and solenoids, check the wastegate lines arent pinched anywhere.

dgeesaman

iTrader: (7)

A +5psi spike is something to be worried about.

I find that in cooler weather about +1psi is normal - by cooler I mean 30F instead of 80F. I don't consider 65F cool enough to explain an increase in boost.

Dave

Rx7_Nut13B

iTrader: (1)

Colder the intake air, the density will increase, thou allowing more O2 in.

90F @ 10psi = 14> A/F Ratio (Appox) Rich-Motor Fine
32F @ 10psi = 15< A/F Ratio (Appox) Lean-PING YOU HEAD OFF.

But like he said Pressure is Pressure

dgeesaman

iTrader: (7)

The wastegate doesn't open like a pressure regulator when boost pressure reaches 10psi, rather it's programmed. Under normal conditions and stock engine flow levels, the duty cycle program maintains enough pressure in the wg actuator to result in a maximum boost of 10psi. It's entirely possible to change something (flow rates, base pressure, boost pill size, etc) so that the resulting boost level is different from 10psi. That's why it is not uncommon to see minor changes in peak boost pressure in cooler temps.

Dave

DaveW

(1) has been answered

(2) What type of "Home-Depot" controller do you have? The needle-valve types are just an adjustable "pill", and do not directly control boost. They still rely on the "duty-cycle" control built into the ECU. Electronic or manual ball/spring type controllers do a much better job of directly regulating the boost pressure.

Snook

iTrader: (12)

I got about 12psi in sequential instead of 10 normally when the temp went to 50 instead of 80s

chinoflyer

iTrader: (1)

Thank you for your input. I guess i will be working on the boost spike issue then.
BTW I have the needle valve instead of the pill to adjusted my boost.

thank you again

chino