alexf20c

DesertRat, you did a 14.55 with a 100.4? Actually, that's not sad at all, if you only look at the trap speed. But I must admit, I've never seen a stock S2000 do 100+mph with an E.T. as slow as 14.55. Usually, their trap speed is in the low to mid 90s.

Was this an official run at the strip or with your "accurate" Gtech device?

UL and xviper - magnificent.

xviper

Still can't find my high school physics book BUT in the light of "overwhelming" public concensus and the higher mechanical authority of "UL", I'll concede this one and begin to carve into that "crow". If I can recoup any dignity at all, I'll continue this with UL via PM.

cravnpup

Hey xviper, don't sweat it man. I'm an engineer and have forgotten about 80% of what I learned in school. BTW, the equation you're looking for is: pV = nRT

If you hold pressure constant (as you would with either FI or NA cars) you'll note that the actual volume of air is directly proportional to temperature....

DesertRat

alexf20c - that was from the Gtech and it is the average of only two runs. Anyway, the Gtech will show a higher TS than the track. From their website "Reason is that the racetrack averages your speed over a 60 feet stretch between two beams and G-TECH/Pro measures your speed at the exact 1/4 mile point."

I do totally agree with you, that the TS seems high compared to the ET. It was actually very slippery on the road = a lot of wheelspin, maybe this is one reason?

ultimate lurker

Right cravnpup. THere's you're answer xviper. There is a common misconception that boost pressure is the determinant of power in FI engines. But what really matters is the total mass of air ingested. For example, a big, efficient turbo at 7 psi will make as much power as a too small turbo at 14 psi. Why? Because the smaller turbo is less efficient and creates a lot of heat. The higher temps mean that the air (which is being forced into a fixed volume) is at a higher pressure, but the mass air flow isn't any higher. That's why the boost pressure would actually have to be higher in hot weather to compensate (which doesn't happen on any OEM cars to my knowledge).

Desert Rat, the 14.5 in those conditions is not unreasonable. Corrected to standard conditions (which is the only way to compare) that 14.5 would equate to a 14.1-14.2 which is pretty decent, especially with 20ft of wheelspin (compared to standard you'd be down about 4-5% power, which would also put your estimated hp numbers near 240 crank). The 100 mph is of course a G-tech artifact.

UL

Silver Bullet

[QUOTE]Originally posted by xviper
[B]
I should have added: