General Discussion Area > Corvette Related Chat
HELP....my so called performance slug
daniel42au:
In respect to your concerns about power output .... Without wanting to be too controversial... what is important to you, horsepower or torque?
I have a 87 Convertible and a 94 Convertible ... the 87 puts out about 240 hp and 330 ft/lb of torque and the 94 puts out 300hp and 330 ft/lbs of torque...interesting huh....
the important part is when then produce those figures...
I got the 87 dyna'ed and to my surprise .... it turned up about 160 rwhp....as you would expect from an instrument which measures output via the rear wheels....but GM measures from the flywheel( and hence the 240hp).... but the plot thickens....because GM doesnt take into account accessories hanging off the engine.
Numbers... numbers.... numbers.... they are unimportant.... because what is important is what happens at the lights!
BOTH cars go 0-60mph in about 6 secs!! even though there is a 60 hp difference.
BECAUSE the thing which gets you mobile from a standing position is TORQUE..... which is the ability of your engine to TWIST around the rear wheels thru the drive shaft, gearbox and diff( which are both geared)....
In the 87 that torque is max'ed in the 3000-4000 rpm range... whilst the max hp comes on line about 5200-5500 range....
So I ask the question... to more knowledgable forum members....
which is more useable Torque or Horsepower?
and where?
at the traffic lights... where 95% of us drive?
or the drag strip ... where 5% of us drive?
cYa
daniel42au
http://members.ozemail.com.au/~daniel42au/
87Z51:
which is more useable Torque or Horsepower?
and where?
at the traffic lights... where 95% of us drive?
or the drag strip ... where 5% of us drive?
Same situation either place.The torque is what gets you moving.
A L98 will out run a LT1 to 60mph on torque alone then
two things happen ;
the L98 with it's TPI intake runs out of breath and the LT1 with it's top end manifold comes on line.
Stock for stock a LT1 will run a faster time than a L98 but the L98 will probably run a better 60Ft.
Inherent problem for L98 cars is the torque is so big low down that traction becomes a problem especially in manual cars.
One of the few situations where it is benefical to bleed off some bottom torque so as not to spin up.
69 DIRTY RAT:
Ok This brings me to a Question I've been wanting to know for a while.....When Racing either at the drags or on the track, IS it better to change gears at the highest torque or highest horsepower? to get the fastest out of the car?
MADVET:
General rule of thumb is to shift at max HP so the engine revs will fall on to your peak TQ.
Repeat as necessary until you win the race....(or run out of gears);--;46
69 DIRTY RAT:
Thanks, that makes sense!
Navigation
[0] Message Index
[#] Next page
[*] Previous page
Go to full version