starchedup

I was told (on a C6) you'd need 100hp per 100lbs to equal the performance of a Z.

IE. The normal C6 is about 200lbs heavier than a Z. Would a C6 need 650rwhp to equal the acceleration (keep up with) a Z putting down 450hp?

How would my 608rwhp Z compare against a super charged C6 putting down 900rwhp? How badly would I get walked?

Be happy to know just how much weight plays into the acceleration formula for our cars.

haljensen

Where did you get the info of 200#'s heavier? My 2008 C6 Coupe weighs aprx 3180# on scales and has 436HP. C6 Z06 are usually rated at 3160#'s and 505 HP.

505HP - 436HP = 69HP. So add 69HP to an LS3 for comparable HP/Weight. Gearing and tires will make a small difference but a 500 HP C6 should run right with a C6 Z06.

harrydirty

Spec weight for 2008 coupe is 3217......so maybe the scales are off?

LTVN68

My ZO6. 505HP / 3160lbs = 0.1598 HP per pound

6.25 pounds per HP

My Honda CBR1000rr ABS, sportbike. 182HP / 435lbs = 0.4183 HP per pound

2.39 pounds per HP

No wonder the CBR wants to do 0-60 in under three seconds.
Let me reassure you, however, that I consider the ZO6 the best of the best! I just had not thought to do this calculation before and found it interesting.

Carnac

Pounds per HP will give you a good idea until higher end aerodynamics come into play (say above 140 mph).

Z06 at 3160 / 505 = 6.25 lb/hp
C6 coupe at 3208 / 436 = 7.36 lb/hp
C6 GS at 3310 / 436 = 7.59 lb/hp
ZR1 at 3333 / 638 = 5.22 lb/hp
C6 convertible GS 3289 / 400 = 8.22 lb/hp

On similar vehicles, pounds/horsepower is a good indicator of performance. Compare either rear wheel hp or engine hp - just compare the same (easiest to compare engine hp since that is what is given as spec by the manufacturer).

To get similar lb/hp in a coupe vs the Z06 you would need about 513 hp (or about an additional 77 hp). This of course assumes similar aero, however the coupe has better aero than the Z06, but the Z06 has better traction (bigger tires). Gearing makes a difference also. Finally, on a road course the handling is different for the different versions of Corvette.

Jim

thebrander

Agreed on the peak HP analysis, but my guess is the real difference between an LS3 and LS7 vette performance is the area under the torque curve. I suppose you could take the LS7 torque curve and scale it by "3208/3160" and point to that curve as the curve required for the modded LS3 to match or exceed. You'd have to also correct for the different redlines. Not sure though. Reality is always more complicated than crazy math.

thebrander

That's an impressively lite C6 Coupe. Is it stock?

Garrett W

That's the dumbest thing I have ever heard. Do the math and it proves that isn't true...

paisa427

Its not 100hp for every 100lbs of additional weight , its more or less, 10hp for every 100lbs.

Vette5.5

As already mentioned, there's other factor's that come into play. First off, a base C6 is only about 100lbs more than a ZO6, and you're not needing 605 hp to stay even. Factor in the ZO6's larger torque, but more aerodynamic drag. A blower on a smaller engine tackles the torque, but add's more weight and other problem's if not properly done. Guess it's easy to see, there's really no cut and dry formula, especially if you're doing some road course tracking.

LEAVINU

No idea where you heard that from or even how that could possibly have any truth to it.

That's about right for a 1LT car while a 3LT will be closer to 3300lbs which is where mine started out at.

starchedup

Yeah I thought the C6 was about 33xxlbs but it looks like its only 3215lbs. http://www.roadandtrack.com/tests/up...ette-coupe-z51

So gearing makes a difference too... Did I read this article right, the Z-51 has a 2:73 rear end? What is it on the Z?

LEAVINU

The Z51 cars have a shorter gear (same as C5Z cars) which would make their shifts shorter 1-4.

Yes, it does look like the auto Z51 car has a 2.73 but the manual is a 3.42 still. The base C6 has the same gearing as a C6Z just shorter redline (6500 vs 7100).

starchedup

Thanks for clarifying.

JoesC5

I still go by the rule of thumb I remember from 50 years ago.

10 HP = 100 lbs.
10 HP = .1 sec in 1/4 mile
100 lbs = .1 sec in 1/4 mile

So, if a C6 weighed 100 lbs more then a Z06 it would need the horsepower difference(69 HP) + another 10 HP to make them equal in acceleration.

PhysiPhile

Wouldn't more weight actually increase acceleration until a certain MPH by increasing friction force (u*normal)? I have to reduce power to limit slipping under 50 MPH. I'd like to see more data on max force without slipping considering various factors like temperature and road surface. I've noticed on smoother roads, I slide even when I'm barely accelerating from a light while on the highway I can nail it at 4k RPMS without slipping.

GMuffley