Originally Posted by chip-3door
No its not, its torque AND multiplied by revs.
Keep peak torque the same and shift it up the rev range and your car gets MUCH quicker because it means you are a gear lower all the time, so your same torque figure@flywheel results in a greater torque @ wheels
aye... so its a multiple of the two. BHP is just a number that sounds great in the bar but has little meaning else where.
As for torque getting you starred and bhp giving you top end.... thats not right.... what gets you going is GEARING and its the same thing that gives you top end.
You need lots of toque to pull away, hence 1st gear in your gear box. Gears simply mutiple the torque, you have to turn the gear round and round more times inorder to get an increase of the torque you have, but thats no real problem if you have a choise of gears.
A typical set of gears would be:
3.52:1 1st Gear
2.22:1 2nd Gear
1.43:1 3rd Gear
1:1 4th Gear
All running through a final drive of say 3:1.
1st gear is needed to get you moving as when the car stationary it takes lots of torque to get going. The other problem is that the wheels start off not turning and the engine (to which you are connecting the wheels is!).
Once your up and running you work your way through the gears into top (4th), which is usually a direct drive. This effectivly bypasses the gearbox and connects the engine to the wheels via the diff.
The engine does not change the max torque it can produce (well most don't). The only thing that changes is gearing. The lower the ratio the faster you will go IF the engine has the torque to turn the wheel.
So where does BHP fit into this? No where really its just a measurement used to express torque in different units.
Alex