>Fm: Ron Katona
>The multi-link rear suspension helps it put down power in a corner or
>over bumps better than a solid axle. It actually hurts acceleration in a
>straight line on relatively smooth pavement.
OK. Yes I've heard that before (and promptly forgot it for this
discussion<s>).
>Weight distribution I can buy
Well then that's a factor in the other direction.
>I get ~3300 for your car (300*11.02), but no matter.
Thanks for the correction.
>1st gear is a steep 4.20. Only legal gear sets in SP are 3.15, 3.23, or
>3.38. The max multiplier would therefore be ~14.2.
Wow! Well that certainly helps.
>Bob's car weighs about 3150 w/driver? That's almost 1:1... slightly better
than your car on
>paper.
Thanks. So much for the tremendous torque advantage of the ponycars that
Scotty talked about.
>2nd gear drops off to 2.49, BTW.
vs 1.98 or 1.99 on the Mustangs, and with the weight difference and torque
in the engines, the M3 still has a significant power to weight advantage
over the Mustangs.
>The shape of the torque curve is overlooked with simple number crunching
>though. That 220 lb-ft comes at about 4400-4500 rpm. Below that, the
>pushrod V-8 will have the advantage.
I don't have a pushrod V-8 and the torque curve on my engine is within 20%
of peak torque from 2000 RPM to 6000 RPM, so I don't worry about a peaky
engine.
>Tire height also matters. That lb-FOOT torque figure is not at the axle,
>it's at a theoretical point 12" from the axle.
Thanks for straightening me out on that point.
>Bob's tires are about 25" tall meaning the arm for the applied torque is
over 12". The torque felt
at the tread is therefore somewhat less than the total 3124 lb of available
force at one foot. We're talking effective gearing here. If
you're running shorter tires, you may still have an advantage. In either
case, it's pretty close.
The standard tires I run (and most ponycars run) are 25.2 - 25.3" tall so
yes it's very close there.
>Looks to me like it's more a classic power/weight/gearing thing. There's
>no magic in the M3's suspension.
I didn't realize the M3's had that kind of gearing. Yes it is clear they
have a power to weight ratio advantage. Though I'm still not sure on the
launch whether the solid axle of my car is better than the weight
distribution of the M3.
>I'll surmise that the secret to the M3's good launch is that its
>powerband is very linear.
So is my car.
>It doesn't tend to bog _too_ badly if you are too aggressive on the clutch,
yet it won't get excessive wheelspin
>(it doesn't have the torque) if you're too aggressive on the throttle.
But from the calcs we did, it does have the torque. More than my car, and
plenty of people have seen me do excessive wheelspin.<s>
>It's been my experience at the track that mildly modified F-bodies are not
faster than mildly modified M3s in the 1/8 mile
I'm not really familiar with the gearing on the F-bodies. I do know their
engines do have a shorter torque band and higher peak torque than my car.
>That's the last part of this equation - traction. You can add power all day
long, but you only get to use as much as you have traction. Once >on a roll,
I'd rather have the low end torque. That's why Bob is more dominant in Pro
Solo than Solo-II. The good launch of the M3 is
>nullified in Solo-II by the V-8s superior low end torque on the roll.
You'll notice the DSM cars, which launch like rocket sleds, also
>dominated the top spots in ESP at the Pro Solo. Different story today.
Interesting stuff. Thanks!
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