Awesome Thread... [Automotive Edition]

http://www.hammacher.com/Product/12005

The Porsche 917 Le Mans Raceway.

Description

This is the full-sized Porsche 917 replica that conceals a 1:32-scale working wooden slot car track faithful to the iconic Le Mans raceway. Painted in the same color scheme and #20 race number?an homage to the classic 1971 movie starring Steve McQueen?the 917 has genuine race-worn GT prototype tires on aluminum three-piece rims and working headlights and taillights. The precisely molded replica cowling opens like a clamshell at the touch of a button to reveal the track within. Resplendent in its handcrafted detail, the raceway is built with realistic landscaping and includes period signage illuminated by working streetlights: the Esso Oil Drop Man near the Ford chicane, the Marchal sign on the famous three-level grandstand over pit row, the Martini barn, and the unmistakable Dunlop "tire" bridge. Hand-detailed aluminum Armco guardrails with weathered wooden posts convey additional realism. Dual analog racing controllers provide precise control for the 12 included limited-edition slot cars, including the dominant racing models from 1970-1971, painted in authentic period livery: a Porsche 917, Ferrari 512 Coda Lunga, and Lola T70. Plugs into AC. Special conditions and guarantee limitations apply.


 
Meh, I'd rather they used that body on a working car than that.
 
Price: $125,000

:blink:
 
That Volvo is nothing.
I know a guy who used to dragrace with a 700hp FIAT Marea! :lol:
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Best time down the 1/4 ?

With the current setup? Don't know yet, we'll wait till spring. Last summer he was still running a K24 turbo (from an S60R) and no tune. He was at about 300whp and was running 14.5-14.8.

You have to also know that this is at 5800ft. Stock T5's run in the mid 16s. You can't compare it to cars that run at sea level.
 
Except it's turbocharged and makes its own atmosphere.

True, but there is still a loss of power. Just not as big as it would be on a NA. I found a couple of quotes that summarize the problem:

Turbocharged vehicles lose power at altitude for various reasons.

A turbo doesn't care about psi. It only cares about pressure ratio. If you are at sea level (14.7psi ambient) and want to produce 14.7psi boost, the turbo workload is 2.0 pressure ratio. Right now, my altimeter watch is indicating 12.02psi ambient. For the same turbo to produce 14.7psi boost, the turbo workload is 2.22 pressure ratio ((ambient+boost) / (ambient). It is working harder to produce the same PSI.

The problem is that when turbos go higher and higher in the pressure ratio metric, they produce less additional PSI and more heat. Hot air = bad.

To compound the problem, the intercooler is less efficient. At altitude, there are less molecules moving across the intercooler fins. It is therefore less efficient at drawing heat away from the intake charge.

Some cars (Sti, I believe) have ECUs that are tuned to reduce boost at altitude. That reduces the stress on the turbo by making it work at the same pressure ratio.

BMW will up boost to compensate for lower ambients. However, it does not fully compensate. That implies to me that in stock form, the turbo has enough headroom to spin faster and compensate, to an extent, for the thinner air.

Throw in a tune and the turbo is working incredibly hard at altitude.

If you compensate for altitude by running extra boost, you have longer turbo spool up times, and you need a turbo capable of pumping the extra boost with lower original engine output. Also your intercooler efficiency changes with air density, if all other factors are equal.

Bottom line is, if you increase boost by the drop in atmospheric pressure, you will end up with near enough to the original power.

The way our cars (Volvos) are set up is that they don't adjust the wastegate, so they don't really compensate for altitude. Turbo lag is a bitch, and before 2500 there is very little hp. On this particular C70, the new tune and larger turbo were set up to compensate, so in the Spring he should set a lot better times.

Nevertheless, up in the mountains we just don't see 1/4 times as good as at sea level - no matter what car. Everything is a tiny bit slower.
 
Did he make 386whp in that altitude ?
 
On the dyno -yes. But he hasn't taken it to the track in its current state.

Just in terms of boost - before he was running 18psi, now this is at 23psi.

Oh this is the track in question:

An STI doing a 15.x? It should be running mid 13s.
 
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The hills are alive..
 
1. Set video to HD
2. Turn up speakers
3. Enjoy concert
4. Change pants


Please excuse the crap at 4:00.
 
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