lets play hypothetical bench racing small vs big car

[trigger]

So if you use the same driver on the same day, which car should be faster? assume weight is with driver and fluids, and HP is on the dyno.

Car 1, the lightweight
2200lbs/244whp = 9.0lbs/HP
2200lbs/220wTQ = 10lbs/TQ, Flat curve
tires = 205 front, 225 rear = 1060mm to the ground = 2.6lbs/mm
not very aero, but small frontal aera = Cd = .41, A = 15.4
CdxA = 6.3


Car 2, the big brute
3350lbs/372whp = 9.0lbs/HP
3350lbs/335wTQ = 10lbs/TQ, flat curve
tires = 315 front, 335 rear = 2.6lbs/mm
very areo, but bigger = Cd=.28, A = 22.5
CdxA = 6.3

also assume the same suspension motion ratios, stiffness, bounce frequency and roll couple.

Tie, the light weight FTW, or the Big brute with more power and TQ? Thoughts?

[XFordGuy]

It depends on the venue. Big tracks favor big HP. Little tracks favor light weight. I'm only a couple seconds quicker than a SPEC Miata at Barber, but I'm over 10 seconds faster at Road Atlanta.

[PerforminNorman]

I agree with that guy up there. ^

[Jim Lembo]

Big car with big power FTW!

[2MchFun]

Originally Posted by XFordGuy

It depends on the venue. Big tracks favor big HP. Little tracks favor light weight. I'm only a couple seconds quicker than a SPEC Miata at Barber, but I'm over 10 seconds faster at Road Atlanta.

Exactly!
....
Drag strip would favor the big HP car.

[Z06phile]

Is the lightweight an Exige?
Looks like a tie to me, but knowing car 2 is a Z06... I voted for it because they seem to defy logic when on the track. It would have to be an autox sized track for me to think the lightweight would have an advantage.

[trigger]

yeah thats what I was thinking when I started doing the math in my head. Exige S vs C5 Z06 on track. ofcourse the Exige would run way more tire but has less TQ than what the numbers are above.

[XFordGuy]

If it makes you feel better, I've lapped a couple Exige S at Barber. I don't blame the car though. Barber is the slowest course I've run. Have you seen any Exige S at TGPR, Dan? That's the smallest "real" track I know of around here. (although I think I'm going to Putnam Park this year)

[zeta08]

At Brainard's road course, a pretty small course, I have no problems with the Loti (c6Z06). I'm sure they're fun to drive but I've not been impressed, especially in the curves.

An SLS AMG was impressive, as was a GTR... Both high HP heavy cars. There was a E36 M3 that was lightening quick in the curves last outing. That was a race car, I think, so lightened a bit and modded.. Of course, the Lotus is probably much easier on tires and brakes than our cars and those parts are smaller and cheaper.

The more I drive my car the more I like the idea of being scared of the car I drive. Sounds silly, but the Z06 still scares me, which is fun. Like a crazy woman, she keeps it interesting. I guess what I'm saying is I want a car I have to actually think about accelerating, not just mash the throttle on turn exit like a mini or something. But light cars can maintain speed and be very fast.

[trigger]

since you mentioned TGPR, as a point of reference, my previous fun car was a CSP prepped miata (also TTD). weighted about 2200 with me in it and made 150whp. with 275 A6's on it I was running consistent 1:08's, managed to blip one high 1:07 for a personal best.

At the same event Dan was clicking off low 1:04's in his 465ish whp beast. FYI the TTA record in a C5 Z06 is 1:04.8.

oh and brakes lasted forever on that miata. I was not prepared for how quick I go through brakes on the Z06.

[XFordGuy]

Originally Posted by trigger

I was not prepared for how quick I go through brakes on the Z06.

Tire and brake costs are definitely the downsides to tracking a Z06.

I think you could have found another 4 seconds at TGPR if you had another 100 HP in the Miata.

[Z06phile]

Originally Posted by XFordGuy

If it makes you feel better, I've lapped a couple Exige S at Barber. I don't blame the car though. Barber is the slowest course I've run. Have you seen any Exige S at TGPR, Dan? That's the smallest "real" track I know of around here. (although I think I'm going to Putnam Park this year)

No Exige S, but I saw an Elise run 1:09s there. It is a fairly small track, but it has three straights that a TT3 car will hit 100 on. The only place I think the lightweight would have an adavantage is through T3.

[XFordGuy]

Most of the Elise's I've seen have been the 140 HP version. The 240 HP Exige S is not much slower than me in the straights. I haven't seen the new Exige S V6 yet. They are sporting 345 bhp, 295 lb·ft and weigh 2,381 lb.