When NOT to reduce weight... Advice?

[kickin_on]

Hey dudes / dudettes,


Previously posted about the possibly bad habit of always defaulting to Racing Soft tires...

How about weight reduction? I usually jump to weight reduction pretty quickly when tuning as it usually improves acceleration, braking and handling all in the one go... (seems more of a pure way to achieve this rather than with power-related upgrades...)

*Can anyone give examples, or have opinions on when reducing weight could actually be DETRIMENTAL to the performance/handling of a car?*

Possibly on older or high-powered cars? Also starting to think maybe my F430 fries its tires because its too light for its power...

Cheers guys 👍

 

[budious]

Depends on the downforce and horsepower with the car. If I'm tuning for Sport tires I normally like to skip weight reductions and just focus on power upgrades and tuning for the stock weight, sometimes on the beefier cars you can go with a single stage reduction. Leaving the weight on the car can make cornering and acceleration more consistent and also reduces the need for aero parts purchases. Tuning a nice car on sports tires without using aero is a fun way to learn some of the aspects of the game.

 

[Adrenaline]

The only downside I've heard mentioned is that weight reductions screw up the Front to Rear weight balance of the car and can cause possible handling issues that actually hurt the car. The other issue, is that when tuning on sport tires, lighter cars have a hard time getting enough traction.

 

[Bones Brigade]

The only downside I've heard mentioned is that weight reductions screw up the Front to Rear weight balance of the car and can cause possible handling issues that actually hurt the car. The other issue, is that when tuning on sport tires, lighter cars have a hard time getting enough traction.

It would be interesting to see if this is modeled in the game. I think when you do a weight reduction there isn't a particular area of the car that the wight is pulled from. It would be interesting to see if it does effect weight distribution. I mean, I don't really think the game takes into account where the particular interior panels are pulled from and which cars have heavier spare tires etc. I think it's just a blanket reduction.

 

[Adrenaline]

It would be interesting to see if this is modeled in the game. I think when you do a weight reduction there isn't a particular area of the car that the wight is pulled from. It would be interesting to see if it does effect weight distribution. I mean, I don't really think the game takes into account where the particular interior panels are pulled from and which cars have heavier spare tires etc. I think it's just a blanket reduction.

That's what one would think, but as I mentioned above, complaints based on experience say otherwise.

Edit: Plus, the physics of Ballast, imply that the GT5 physics are more than capable of discerning the differences in weight front to back and their effect on overall balance.

Edit2: More food for thought, on the complexity of the GT5 weight physics, remember that when in an endurance race, fuel weight slowly dissipates in real time. Although, I don't recall anyone mentioning balance issues occurring when this happens, which has lead people to believe that the weight is reduced in an unbiased fashion. So, I don't know.

If you want to look for the thread that spoke about weight reductions and F/R balance, it was done on the Shelby 350GT. That's all I can really remember.

 

[kickin_on]

Hmmm... yeah makes a bit of sense....

Slowly starting to come around to the idea of not even touching a car until ive driven it and assessed exactly which specific areas need attention and what should just be left alone...

I think GT5 has enough realism in individual cars' physics etc. that we can afford to be that technical...

Also think the effort put into the physics of GT5 to ensure each car has specific and individual handling charateristics is too beautiful and satifying to reduce this at a cost of fiddling around for the sake of it...

 

[budious]

Edit2: More food for thought, on the complexity of the GT5 weight physics, remember that when in an endurance race, fuel weight slowly dissipates in real time. Although, I don't recall anyone mentioning balance issues occurring when this happens, which has lead people to believe that the weight is reduced in an unbiased fashion. So, I don't know.

It becomes more noticeable on production cars in endurance mode than with race cars because those fuel cells are usually located just behind the driver and have a much more even weight distribution. So the fuel ballast, to speak, is positioned differently depending on the car.

 

[Ronald6]

Try a Caterham Fireblade in an endurance race. Its super light weight makes the change more noticable.

 

[kickin_on]

Try a Caterham Fireblade in an endurance race. Its super light weight makes the change more noticable.

Does this mean you would expect performance to suffer as a result of weight reduction for this car? Traction etc...

I'm dying to purchase one of these so it would be a great tip so I dont **** up the tuning... And I could possibly also use this as a lesson for similar cars... (or as close as you're gonna get to the Caterham :-p )

 

[iMeijer]

Traction will decrease a lot online. Try the ferrari 330 stock and after that a fully weight reduced version. It will slip and slide all track long. Offline it's no problem though, so test your cars online and they will do magnificently offline.

 

[GTP_roadrunner]

From what I can remember, a further weight reduction didn't do good on my Lotus Europa '71, since it had so little weight, unable to get traction on the rear wheels, due to the missing (or only in small amount existing) weight transfer. Hope I got that right

Might be better for that car to increase power instead of decrease weight...

 

[Adrenaline]

From what I can remember, a further weight reduction didn't do good on my Lotus Europa '71, since it had so little weight, unable to get traction on the rear wheels, due to the missing (or only in small amount existing) weight transfer. Hope I got that right

Might be better for that car to increase power instead of decrease weight...

While this may be true, I think it's an unfair comparison.
If you leave the suspension unchanged, despite a 2-300lb weight difference, then it's only logical to expect some issues.
On the other hand, remove that 2-300lbs, adjust the suspension to compensate for it, and then I assume the story changes.

Adjusting the suspension is a far better solution than leaving weight on the car, simply to achieve proper weight transfer.

 

[Ronald6]

Does this mean you would expect performance to suffer as a result of weight reduction for this car? Traction etc...

I'm dying to purchase one of these so it would be a great tip so I dont **** up the tuning... And I could possibly also use this as a lesson for similar cars... (or as close as you're gonna get to the Caterham :-p )

Suffer? No. Less weight will make it even faster. You just need to be aware that the rear end will be lighter than when you started, and the COB (center of balance), aka pivot point, of the car will shift forward.

It's noticable during the Grand Valley endo. It's short enough you don't need any gas, but will run the tank dry enough for the missing weight to be noticable.

 

[TT3AZ]

For drag racing, put 0 weight, and ballast position 50. This is a easy trick to gain a little bit better traction. Depending how your suspension is set up, you will either feel much better traction, or just slightly..

 

[Jacob]

I have a maxed out Lotus Esprit that I bought for the "British Lightweights" cup, and bought weight reduction 2 and got it down to 1199, and now that I've gotten used to it, I tried doing the weight red 3, and wow. There was a lot more oversteer, it almost felt like all the weight was taken from the front. So my advice would be to learn the car's characteristics, and then lighten it after what kind of handling you want.

 

[GTP_roadrunner]

While this may be true, I think it's an unfair comparison.
If you leave the suspension unchanged, despite a 2-300lb weight difference, then it's only logical to expect some issues.
On the other hand, remove that 2-300lbs, adjust the suspension to compensate for it, and then I assume the story changes.

Adjusting the suspension is a far better solution than leaving weight on the car, simply to achieve proper weight transfer.

Ok, I'll try that. A lovely car by the way...

 

[budious]

For drag racing, put 0 weight, and ballast position 50. This is a easy trick to gain a little bit better traction. Depending how your suspension is set up, you will either feel much better traction, or just slightly..

Interesting, I had noted a similar flaw with setting a 1KG ballast which had shown significant improvements in endurance mode. I should have been more thorough with my testing though, as even using your method showed a significant improvement in offline practice mode.

Endurance Physics has a "glitch" thread. Think'll just change it to "Ballast System has a "glitch"...

I have been working the on the McLaren MP4-12C for the tuning contest and had my build down and running pretty consistently on R246. X:YY:ZZZ" lap times all within a range of 1" on a 10 lap run. Trying the 0KG ballast at -50 I set my new best lap time record with the car and the cold runs (first two laps) showed the most gains. Once the tires warmed the advantage of the ballast glitch was less obvious but it still got the best lap time award, consistently about .5" faster on average for laps. Good find and thanks for sharing.

 

[Nicktune]

Ok Same turn/same speed....

A heavier car will have more centrifugal force tending to make it leave the course...but will also have more downforce on the tire...(vertical force)
Grip is equal to the side force divided by the vertical force on the tire (coefficient of friction)

It is the ratio of side force to downforce that's important....

 

[Ronald6]

^^ Search for Dr Beckmans "the Physics of Racing." He explains that less weight is better for cornering. But above 55 to 60 mph aero downforce starts to play a major role.

 

[budious]

^^ Search for Dr Beckmans "the Physics of Racing." He explains that less weight is better for cornering. But above 55 to 60 mph aero downforce starts to play a major role.

I don't think what he's saying is that heavier is better. He's saying that heavier is better lower to the ground but when the car is lightened you need to raise the ride height to compensate for the loss of lateral weight transfer to maintain the proper ratio of vertical force on the outside tires.

 

[kickin_on]

I don't think what he's saying is that heavier is better. He's saying that heavier is better lower to the ground but when the car is lightened you need to raise the ride height to compensate for the loss of lateral weight transfer to maintain the proper ratio of vertical force on the outside tires.

Now THATS very interesting!...

 

[frankygt-r]

if you need a car for deep forest, a lightner car is the way. my mazda roadster can run at 1.20 on sport soft.