Don't forget that "ambient" temperature to the G-tech is the temp inside your car (where it is mounted). So I expect that most cars are close to a narrow comfort range of 68-72 F.

 

Very true. The only time that it can be heavily skewed, is if it is mounted in direct sunlight. Then all bets are off! The surface of a black object can be as high as 100 deg F, even when the interior is 70. I checked it once in my BMW using an infrared gun and got a dash temp of 115 on a mid day at 80 deg outside temp. I suppose if it is mounted near a AC register it could go as low as 50 deg. Either way, the internal sensor is going to save the day and correct for it. With the iPhone program, you have to calibrate it each time you use it. The funny thing about the phone is that it is usually starting at 98.6 deg F...since I keep it in my pocket

 

Ambient (or any air temperature) is NOT used in Gtech's calculations.

 

LOL! Now I'm Confused

 

The Gtech was "calibrated" at 2 different temperatures. This is just to make sure it works within the range of temperatures. I also do not think it using altitude in its calculations.

 

OK, but then how does it know which calibration is correct? (solid state accelerometers are pretty sensitive to temperatures....)

 

If the temperature is outside the ranges estabished, it will warn you that it will not work.

 

gosh this sounds like fun... too bad i'm located in asia... maybe i'll hunt down a unit and contribute "comparable" data...

stacy - do you know if there is an online store that you know carries these devices?

 

Thanks! That would be the answer. I knew they got some great numbers out of that device. The engineers know their stuff....

 

http://www.gtechpro.com/prod.html


Read up on the differences!

Stacy

 

add me to the list Stacy!

 

My interpretation of the manual suggests that if the temp is too far from the temps the unit was calibrated at in the factory, it will advise you to re-calibrate to a wider temp extreme. This situation is apparently very rare, so I doubt it will be an issue.

 

99 C2 with 2002 C4S mufflers and centrifuge SC running 7+ pounds of boost using Gtech RR Pro provided to me by some loonie.

379 and 387 in 60F temps. 3rd gear pull from 2500 rpm.

 

So that's a 3.4L engine (right?) with SC putting down ~380 NET HP? Not wheel HP, but NET, which is NET of drivetrain loss, friction, wind, slope, etc.

I've got to assume you're impressed by those numbers?
CATTMAN

 

This sounds about right considering he is 7+ PSI of boost.
Do a little math and:
Assume his 'stock' car is around 251 net RWHP and with is charger(7.1PSI)
1999Porsche911 is making about 18.59 net RWHP/PSI of boost

Now assume my 2005 S 'stock' is the same as the one we tested(give or take) is making 291 net RWHP.
I am making 5.9 PSI of boost with my charger and 401 net RWHP so I am making around 18.6 net rwhp/PSI of boost.....which is almost the same number of net RWHP/PSI of boost as 1999Porsch911.

His car undoubetly IS faster due to the fact he is building his boost earlier than mine and his car is lighter....but....at least we know that 1PSI of boost=around 19 net RWHP !
Kinda neat and YES they are alot of variables BUT none the less alot of fun.
1999 and I are sorta talking about meeting up half way across the country next year to test drive each others car's,LOL!!!!
By then mine will KICK his a$$,LOL!

Stacy

PS the Gtech is being sent to keninirvine next(and is already on its way) to test up against the brand new model already purchased.I will then be accepting the anyone who wants to try it next!
Pm me and I will book you in!