10 GT3

This should be a no brainer. ALWAYS go for lowest weight. Why? Lighter weight means more effective use of all the components of the car: suspension, brakes tires steering and drivetrain. The advantages you have have is you can brake later than a heavier car, have higher grip in the corners and carry more speed coming out. Assuming power to weight is equal across the powerband, you also won't be pulled on the straight. The only disadvantage is on very high speed tracks where aerodynamics becomes a factor. If you start seeing speed over 150 mph; if aerodynamics are equal, the higher HP car will always pull ahead.

FredC

Someone please help me....

mikew968

In GTS-2, running on tracks like Mid Ohio, Putnam Park and the like, lighter cars seem to be the winners. The best GTS-2 car has run high 1:36's on the pro course at MO. Now that is cooking for a "2" car and it is like 195 hp!!!

Bryan Watts

Your "no brainer" just doesn't play out on the track. The aero advantage of more power certainly comes into play before 150 mph.

Sean F

Leave this thread and never look back

bobt993

SAys a guy with a GT3

Bryan I agree, I car high hp car is really tough to keep behind you and kills you on the start. The race Wong and I had at Summit in March had a new M3 running slower lap times, but with massive power (class up) to contend with. I had to throw a big block into T3 to get enough turns ahead to clear him on the front straight. Wong was not so lucky and it blew his entire race. He would get by in T9 or T10 and get re-passed every time. Over a 100mph HP rules.

The only issue is expense on consumables.

joseph mitro

one of the biggest factors that's not discussed much here is the track layout.
shorter track with short straights and many corners definitely favors a lighter car with less power. a track like VIR favors a higher hp car. but not all tracks are like VIR

also, so many other variables about the individual car, such as aero, Cd, track, contact patch, gearing, etc etc.

Streak

My two cents:

The cars that seem to dominate GTS 2 around here are BMW's for a few reasons. First, more power. Second, more power. Third, more power.

Generally, as compared to my 86 911, they are newer by a fews years, have bigger brakes with ABS and more hp. Some guys will take an M3 and load it up with ballast to get into a lower class. Like 300+ pounds. They also use restrictor plates which have the very fortunate effect of raising torque while lowering hp.

In a nutshell, go for power as in the real world power wins. By real world I mean the amateur ranks. I'm not Pat Long and the Bimmers kickin my *** aren't driven by Pat Long either but the results are clear in the non-pro ranks. Maybe Leh Keen can take lighter and and beat more hp but not many Leh Keens out there in the club race scene. In the hands of hobby racers, power wins.

cgomez

Agree. Also most of our tracks in the US are really high speed (90mph+ average lap in a 300hp car). The lower weight is only an advantage in slower tracks like most secondary tracks in England or where Top Gear or EVO do their test (500hp cars do max speed of 110mph).

Just look at the results of any of the US series. Lotus can't win at all, even with a slight power/weight advantage. V8 M3s and Mustangs are killing the less powerful Pcars in Grand Am GS

also, in a series like NASA GTS restricted only by power weight, you have other very relevant variables that you can use freely and favor the higher HP car bc it has more power to overcome gigantic tires and Wings. with a bigger Wing you can more than offset any apex speed advantage of the lighter car.

Only if you restrict tire size, wing size, you start giving some chance to the little lighter car.

Bryan Watts

I've got some old video from Barber somewhere that shows high HP is still the way to go on rinky-dink tracks. Even on "short" straights, if you can get by with a power car or make one pass stick into a corner, you can play defense in the corners and stay ahead. Generally, the more powerful car will have a better torque curve (more displacement, better breathing, etc), so over-slowing in the corners compared to the light car and then out-dragging between the corners is a simple recipe for keeping a lighter car behind you.

I know I sound like a broken record, and I honestly think that lightweight is more fun and can make for a very fast laptime with open track...but, I'll always edge towards more power/more weight when choosing the best race car. It only takes one move to get in front (or none if you out-qualify), and then the more powerful car is easier to keep in front and get through traffic with. Obviously, there's a limit...a 5000 pound car wouldn't be good at much of anything.

joseph mitro

yea, i've seen that video before. i agree with "only takes one move to get in front (or none if you out-qualify), and then the more powerful car is easier to keep in front and get through traffic with."

also agree with streak....there are so many other factors in play here (bigger brakes, ABS, aero, wider tires, gearing, chassis design, etc) that it's really hard to make an apples-to-apples comparison. all we can do is make generalizations.

mark kibort

Bryan,
you are talking about a car that has MORE hp to weight, not just HP. as I have been trying to explain, if the HP to weight is the same, the acceleration will be the same, especially if I qualify it by "net HP" Now, what that means is that aero losses have to be in proportion. more poweful cars DO NOT have better torque curves and dont even know what that means . you want flat HP curves, you want close gears if you dont, all this, gives better average HP to the wheels over a lap. (think of it as measuring out HP-seconds or a unit measure of work, but I dont want to go there )

I totally agree with the greater power or power to weight situation you talk about in your post below. Yes, more power, allows you to blast down the straight and then drive narrow in the turns against a lighter car. But, make no mistake, if you have a smaller car, with better aero drag, it will counteract the losses in the overal ratio vs a larger car with both having the same HP/weight ratios

And yes, I aways think and have seen, that the lighter cars at the near the same HP to weight ratio work the best. as far as optimal "torque" curves, or Hp curves, GTS does factor out the advantages with the "More torque than HP numerical calculations", so it becomes less of an advantage , if anything gained at all. (unless you are competing against a same HP/weight car that is high strung, and you are already calcuated down at the same values, and you have the big displacemet type curves)

mark kibort

Fred, the point was based on talking about same hp to weight ratios. same ratios, same accelerations. (yes, there are other factors)

If you were competiting against other higher classes, then your point is understood. But, if not, and you have the higher hp to weight ratio, even though your hp is less, then you will be running around them. unless of course you are talking the same car, same drag, where the drag comes into play. (hp-drag ratios.

mk


What I said:
Originally Posted by mark kibort
I think here, we are talking about same HP /weight ratios, which wouldnt give that kind of advantage. more powerful, but less hp/weight, and you would be running around them at the glen!

Streak

Holy ****! That's never happened before!