G-Tech Pro RR newbie

[Rusty]

Yeah

I'm just interested as my runs were at 3750lbs and based on your calcs above my car weighs 1530Kg (Ozs = Avus) and has no AC but I make up for that difference. So rather than 1700Kg my car might weigh 1620Kg or 3572lbs, might have to go and do a few tests as it would seem that I've over-estimated the weight somewhat. I suppose it's all a relative measurement so I shouldn't worry so much. Consistency is the key and knowing a basic setup to test against.

[EspenW]

A very interesting drag racers equation is the following:
Multiply 1/8 time by 1.54 to get the estimated time in the 1/4
The 1.54 factor is amazingly accurate.
This way, you can measure 1/4 time by running the 1/8th mile. Less risk of hefty fines and whatnot.

[Rusty]

Yeah, holding it flat in 3rd and 4th isn't a great plan on the road.

[EspenW]

Did some testing last night. Got to test in 3rd gear for the first time, and as expected, numbers (especially torque) were way up, since the turbo has time to boost, and less power is used to overcome rotational inertia. Test weight: 3560lbs
10 degs C, 55% humidity, 300ft elevation, 1011mb barometric pressue gave a SAE correction factor of approx. 0.96.
360hp and 320ft/lbs at the wheels. Uncorrected numbers (as would show on a G-tech) were approx 370hp. Note that unlike the G-Tech, this computer compensates for aerodynamic drag (approx 25hp at peak power in 3rd.)
Approx 0.5G's peak acceleration in 3rd.
Numbers in 2nd gear were 335hp and 287ft/lbs. Torque suffers the most in the lower gears, since the turbo does not have enough time to spool.
Last time I tested, ambient was -2 C, and it is easy to tell from the graph and feel that the turbo spools slower in the warmer weather. Changes since last time included new spark plugs, and I have gotten AF dialed in, so it sits at 11.8-12.6 under boost. Used to be at 13:1+ with former owners setup.. Had to bump fuel pressure to close to 6bar, though. Not too concerned about that, since I know for a fact that MTM used to run RS2 injectors at 7bar. Car feels fast, but missing that brutal kick in the back at 4K that one gets at freezing temps

[Ducky]

Watching this thread with interest now as I also have a G-tech RR , but unable to use it as yet due to a recent operation. I wondered if anyone had strapped it to a bike as yet...I was thinking of hooking up a cig lighter adaptor on my bike to try it (when I can)?

[EspenW]

Watching this thread with interest now as I also have a G-tech RR , but unable to use it as yet due to a recent operation. I wondered if anyone had strapped it to a bike as yet...I was thinking of hooking up a cig lighter adaptor on my bike to try it (when I can)?

Testing a bike sounds like an interesting proposal

[S2central.net]

I got a few power runs with the lower portion of RS2 airbox fitted. You can actually feel the difference in the butt dyno. Attached is G-Tech comparison of best run with ABY airbox and best from that small test on the RS2 airbox. See how the graphs converge at peak revs... The gains are more noticeable in the mid range.

Using same fuel (95RON plus splash of Nitrox)
Same MAF attached to upper portion of ABY airbox
Same paper air filter
Same ECU and software
Same stretch of road
Similar weather about 12 degrees ambient
The air guide behind the headlight is NOT fitted though

I got some Shell 97 in the tank yesterday and the car is flying

Gonna get the RS2 air guide and MAF fitted next, but I should really get some runs on stock ECU with and without the RS2 airbox for comparitive purposes.


Cheers,

Paul

[S-Express]

Amazing results for just an airbox! Just shows how poor the standard one is then.............

[S2central.net]

Yeriknow, but in fairness - not all the runs are *that* strong - I really need to get some more and average out the results.

Its amazing the difference if you do a cheeky run on a slight downhill - the GTech gets fooled into thinking you have ~300bhp at the wheels so the runs need to be on the flat for any kind of consistency.


Cheers,

Paul

[EspenW]

Start from the same exact point each time, that way the data won't be skewed by dips and bumps. I find second gear best for such comparison runs, as you can get rolling in second, and not having to shift into the next higher gear provides the most consistent results.
I measure less power on downhill runs... the unit gets tilted and measures less acceleration.