If I drove the car for a 15 minutes and then let it sit for 1.5 hours and started it up and let it idle for 20 seconds and then drove it 0-90 at wide open throttle would it get full boost or does the computer reduce the boost.

Does the mini reduce boost until the car has been driven a little or can you let it idle a say 20 seconds and take off and will it get max performance.

The reason I ask is I have tested 3 cars at the track and with my gtech pro at a location other than a track

Same cars / same track /same day

Mustang GT Track 3 runs 14.2-14.4 @ 99-100 MPH

RSX S Track 3 runs 14.9-15.1 @ 92-94 MPH

R56 Cooper S Track 3 runs 15.6-15.8 @ 83/85 MPH

Mustang GT Gtech 3 runs 14.3-14.4 @ 98-100.5 / Non Track location

RSX S Gtech 3 runs 15.0-15.2 @ 92-94 MPH Non Track Location

R56 Cooper S Gtech 3 runs 14.7-14.8 @ 91-93 MPH Non track location

My theory of why it wont run at the track is the staging lines have been 1.5 hour wait and when the car idles off and on for a few seconds here and there to move the car up and then only idles 10-20 seconds before you start and go wide open 0-90 the car is not getting full boost after 50 MPH and I can feel it. At the location other than the track you drive there at normal cruising speeds for quite some time and then stop for a few seconds with the car still running and then go 0-90 and what do you know the car runs consistently where is should 14.8 @92. I even ran at an eight mile track tonight and the same thing happens the car ran 2.2 60 foot but the eight mile is weird 9.70 but at only 70.6 MPH the car just seems to flatten out at 40 or 50 MPH. It is amazing the car can run a 9.7 without running at least 74MPH this means if the car did not flatten out it would run what my gtech says time and time again 9.5 @ 77.

I have a stock R56S automatic with no mods other than tires and suspension so it must be something about the ECU not wanting to go to full boost until the car is driven a bit.

I really had no intention on going to different drag strips and spending all this time with the GTech and testing 3 cars but I was baffled and think this may be the answer.

 

My guess would be no, but I have no idea. Typically when the car is in "Warmup Mode" the aux air pump will be on, and it will run a "Warmup Tune Fuel Trim" until the car is fully warmed up. I'd say your car probably wanted to run a less than optimal mixture and timing variation until the car was warmed up.

Depending on temperature you car could also be heat soaking. Those turbo's get REALLY hot.

FYI you should warm your car up to operating temp before revving the engine much past 4k RPM's. You can cause serious damage to your engine by just starting it up and taking off down a drag strip .

 

Based on your staging line description it sounds like your engine is most likely highly heat soaked [especially the intercooler and turbo] if you're idling on and off for 90 minutes, and then doing a run without any previous airflow to bring the temps back down to normal street-driven temps. If I was in your shoes I'd be strapping on my OBDII scan tool and perhaps some thermocouples in strategic locations to closely observe temperatures since you're in such an odd operating environment.

 

Yes, your premise is correct. The ECU does not provide full boost until the engine reaches full operating temperature. Also, the ECU reduces boost above 70mph unless the Sport button is engaged and the DSC is off.

 

I've still not seen proof from ALTA who claims this to be true. I've asked twice. Third times a charm?

 

The ECU definiately reduces boost until the engine is fully warm.

 

do you have a source for that info?

 

Thanks for the input

First off it could not be heat soak because I was in the staging lane for 90 minutes but I only started the car once because I pushed it and they had a good system where you only had to move up every 20 cars.

I think I am a good source because I have experienced what seems like some kind of ECU adjustment that does not let the car run all out unless it is at the proper coolant and oil temp.

I wish I new for sure but because the car does not have a temp or oil pressure gauge I will not know for sure.

 

Try letting it idle while waiting in line (at least the last 10 minutes of waiting). Should keep the engine hot without really heating the intercooler too much.

 

That makes it important to make sure the car is fully warmed up before an autocross run. As there is no temperature gauge, how do you know when the car is warm?

 

The ECU reduces boost in a variety of occasions and low water temps are just one. As is low grade fuel, detonation, traction, etc. etc. But yes it can take what seems like a LONG time to get full boost.

Hope that helps! Let me know how I can help further!

 

Might have one of our gauges in the car. The boost and water temps are the most commonly purchased from us. Let me know!

 

Get a boost gauge and mount it in the car. You can see it do it. I have repeated is many times on my 07. Haven't tried it on my 08 but I assume it to be the same. Once the sport is engaged and DSC turned off, boost comes right back up. We also have this same phenomenon in our 07 Test Mule. Might vary on other vehicles, but two separate cars we own did the same thing. I also think Scott48 published similar results in his car a few months ago.

Hope that helps!

 

Water temperature doesn't have anything to do with whether the car is warm or not. My water comes up to temp in 2-3 minutes of driving. Oil on the other hand can take 10-12 miles to come up to temp (10-15 minutes of driving).

You can bet your car won't like you if you're driving down the drag strip with your oil at 90-100 degrees (At 90 degrees my car idles at 60 PSI of oil pressure, at 180-190 it idles at around 18 PSI of oil pressure). Viscosity at low temps can and does affect how much oil can get to the places it's needed.

 

when you turn the DSC off (with sport button engaged) does the extra boost come at any speed or above 70

 

Does ASC also have the same effect on boost?

 

I believe it has the same effect. But all of the mules have had DSC.

Let me know!

 

This is a good point. Looking at your signature I can assume you still have an R53. They DO warm up FAR faster than the R56 models do. It can take 20+ minutes for an R56 water temp to come up to operating temps and interestingly roughly the same for the oil. On the R56 it cuts boost until water is HOT.

Thanks for the help!