Topic: How to get a extra10hp

[snaponbob]

There is nothing "green" about F1's future specs. They will still be staffing with literally hundreds of employees and moving dozens of tons of equipment to and from events. Hell, E85 specs in ALMS winds up using MORE petrochemicals than it is "saving".

[Uranium-238]

I know Bob, and that's why it's so silly. How many other times have "green" initiatives been proven anything but? All about appearing green, not being green.

[Brad Kenny]

Got an idea...

Lets all go get in our SUBURBANS and go down to the city hall and protest with our big PAPER/CARDBOARD signs, tieing up traffic for hours.

Then we get to kill trees and the environment all at the same time just to "be green".

"Going Green" what an oxymoron...

IMO

[snaponbob]

Got an idea...

Lets all go get in our SUBURBANS and go down to the city hall and protest with our big PAPER/CARDBOARD signs, tieing up traffic for hours.

Then we get to kill trees and the environment all at the same time just to "be green".

"Going Green" what an oxymoron...

IMO

ZACTLY !!!!!!!!!

BTW, my 04 3.4 Silhouette gets 24-25mpg at 70-75MPH. I'm doing some of MY part. If I don't hammer the gas pedal on Streak, it does 29 @ 70 on 91 octane. That said, there is a case to be made for NOT getting rid of my tow vehicle (97 5.7 Express Van) as the carbon footprint of a new vehicle that gets just a few more MPG's is FAR greater than the 97 due to total footprint of the new vehicle's "birth" and delivery.   

[Dave@DDMworks]

For racing is the only reason I could think... revs are how you get power out of small displacement. F1 cars rev to 18,000 and they used to go higher!

Given a specific displacement you are limited to how much torque you can make with that displacement based on cylinder pressures, surface area of pistons, tangent to the crank, etc. Most modern engines make anywhere from mid 60's to mid 70's ft/lbs of torque per liter naturally aspirated, examples:

2.4L solstice  167 ft/lbs - 2.4L - 69.5 per liter
2.0L S2000 153 ft/lbs - 2.0L - 76.5 per liter
Ferrari 430 343 ft/lbs - 4.3L - 79 per liter
LS7 475 ft/lbs - 7.0L - 67.8 per liter
LS3 418 ft/lbs - 6.2L - 67.4 per liter
2.2L S2000 162 ft/lbs - 2.2L - 73.6 per liter
1.8L Miata 116 ft/lbs - 1.8L - 64 per liter


Most cars you are going to find end up in this range, so if you are limited by displacement (which Formula 1 is) you reach a point where you can not make any more torque with the given displacement, so to go faster you need more horsepower, or in other words you need to make that same max torque per liter just faster. Since horsepower is a calculated value and is not actually recorded, by looking at the formula for its calculation - (HP = torque x RPM/5250) the longer you can hold torque out, the more horsepower you will make. Given 2 engines that are both 2.4L and make 75 ft/lbs per liter (180 ft/lbs total) but the first one makes it at 6000RPM and the second makes it at 18000 RPM, the calculated horsepower for the first is 205HP and the second is 617HP. Also with the other major advantage to a higher revving motor is you are able to hold a gearing advantage over the other motor. The graph below is both therotical motors above but this time graphed out to the same axle speed in each gear. As you can see the motor making the torque at 18000RPM puts more power at the wheels because of the huge gearing advantage it can run. ( The graph below is making some pretty crude assumptions about a theoretical engine torque at different RPM's and is only meant to show a general characteristic)



So now that they are going to only be able to turn the engines 10000RPM, the gearing will have to change also, but because they will not be spinning the motors as fast, which requires very light components, they will be able to make heavier components that can take higher cylinder pressures and with the turbo make more torque, just at a lower RPM and make the same power at the wheels. However to match the same power at the wheels and axle speed the new motor would have to make peak torque of 333ft/lbs. So with that, we should end up with cars that have more power under the curve, better acceleration overall and lots of money being dumped into turbo development, intercoolers, wastegates, blow off valves, etc. The only way I can see this being green though and saving fuel, is that there will not be as much frictional loss with the 4 cylinder over the 8.

Talk about thread drift...

Dave

[Kuprito]

In short:

There are 2 ways to make torque, Displacement - Boost
There are 3 ways to make power, RPMs - Displacement - Boost

Best thing is improving all 3

(Boost is related to the compression ratio).

[Graywolf]

Another problem with hi revs for the Lnf is the timing chain. My head is ported/ferrea valves and springs etc. Bates spring tensioner etc. My chain was streched out and chipped one sprochet-cam sensor light alerted me to the problem. I was shifting at 7,500rpm on road racing couse. I suggest if you plan to run high rpm you have the chain/sprochets cryo treated which might help

[SKY888]

Another problem with hi revs for the Lnf is the timing chain. My head is ported/ferrea valves and springs etc. Bates spring tensioner etc. My chain was streched out and chipped one sprochet-cam sensor light alerted me to the problem. I was shifting at 7,500rpm on road racing couse. I suggest if you plan to run high rpm you have the chain/sprochets cryo treated which might help

Tom .....this is good info!

I'll probably have that chain/sprockets cryo treated.

thanks!