Lighter Car Means Faster Car..... Does It?

[GNBRETT]

Makes me wonder if making my Trackhawk lighter and lighter is a good thing or bad thing.
IDN Maybe cause the Plaid is AWD it just benifits from being heavier. Seems odd to me tho.....

Maybe the extra weight helps more than it hurts when trying to make more and more power on the street.
Everything is fast at the track with a prepped surface but on the street it seems the extra weight helps.

 

[Speedy!]

I'd say too a point and weight distribution as well. Demon 170s for example seem to do better with weight moved rearward not necessarily lighter.

 

[MiHiHemi]

My ’33 Ford, with a 350, weighs in at 2500 lbs. My SRT Challenger, with a 440 stroker, is 4200 lbs. The ’33 is much more of a head snapper than the SRT. Don’t know how they compare side by side yet. Just think of trying to push a bowling ball then a baseball.

 

[GNBRETT]

Normally the lighter the car the faster it is and when pertaining to a prepped surface like a drag strip that definately is the case but on the street that seems to vary a lot.

Im just not sure when that balance tips the other way on the street. Like when is less weight more helpful then more HP like where in the line drawn or do I want a vehicle as heavy as possible with AWD that makes a shit ton of power.

But again where do u draw that line? A TRX weighs like 6500 lbs but no matter what u do to it it will never be as fast as a modded Trackhawk it just weighs too much but when does that extra weight hurt vs. help is what im trying to figure out?

They have a carbon hatch out now for the Hawk. It weighs less than the glass on a stock Trackhawk hatch. Is that gonna help or hurt and they will be releasing CF doors and a CF moonroof replacement. Am I going backwards if lose all that extra weight thats what im wondering.

 

[Jimmy N.]

Technically fast vehicles can be plenty heavy. Think land speed.

That Tesla is probably slower after removal of that many body panels, creating tons (no pun intended) of aero drag.

 

[GNBRETT]

Yes I considered the aero part thats definately not helping things. Fastest Plaid goes 8.56 @ 162mph but the thing was completely gutted dash and all but did have body panels. But, thats a prepped sticky surface.

Technically fast vehicles can be plenty heavy. Think land speed.

That Tesla is probably slower after removal of that many body panels, creating tons (no pun intended) of aero drag.

 

[vortecd]

Normally the lighter the car the faster it is and when pertaining to a prepped surface like a drag strip that definately is the case but on the street that seems to vary a lot.

Im just not sure when that balance tips the other way on the street. Like when is less weight more helpful then more HP like where in the line drawn or do I want a vehicle as heavy as possible with AWD that makes a shit ton of power.

But again where do u draw that line? A TRX weighs like 6500 lbs but no matter what u do to it it will never be as fast as a modded Trackhawk it just weighs too much but when does that extra weight hurt vs. help is what im trying to figure out?

They have a carbon hatch out now for the Hawk. It weighs less than the glass on a stock Trackhawk hatch. Is that gonna help or hurt and they will be releasing CF doors and a CF moonroof replacement. Am I going backwards if lose all that extra weight thats what im wondering.

Consider the stock tires on the tesla. Just good tires would fix the spin. Do you think you are going to drop 700 lbs from your jeep? Give me the lighter car all day

 

[GNBRETT]

Yea, but that lighter car doesnt have AWD usually and thats true a much better set of tires would have helped with the spinning but stock tires hook like velcro at full weight. Im gonna drop about 500-600 lbs from it. Right now its sitting at 5050 lbs. I mean dropping another 250 or so from what ive dropped already is what I meant to say....

Consider the stock tires on the tesla. Just good tires would fix the spin. Do you think you are going to drop 700 lbs from your jeep? Give me the lighter car all day

 

[redraptor]

I'd say too a point and weight distribution as well. Demon 170s for example seem to do better with weight moved rearward not necessarily lighter.

I've said for years any weight you can take off the front and add to the rear will help.

 

[redraptor]

Makes me wonder if making my Trackhawk lighter and lighter is a good thing or bad thing.
IDN Maybe cause the Plaid is AWD it just benifits from being heavier. Seems odd to me tho.....

I'm not the only one here who has used some type of ballast to overcome a spinning issue. Heavier? yes. Quicker e.t.? yep.
If that Tesla weighed half as much with the the same amount of torque it would spin those tires like a stock Hellcat. You would have to overcome it with better tires and suspension, or more weight.
Removing weight or adding horsepower seems more difficult to see once you're so fast, like the 9's vs 13's.

 

[Jack_Toepfer]

Lighter is always able to be faster than heavier. It's in the math.
Getting the power to the ground is a different science entirely.

 

[Speedy!]

Lighter = Faster hasn't proven true in practical application. Watch some of the racers who put ballast in the rear of the car and pick up ET. It's a function of traction and applying the power to the surface.

O'l Cleeter had to run two 100lb steel plates in the rear of Leroy to get it down the track quick. That was on a trick suspension and money no object setup.

 

[Jack_Toepfer]

Lighter = Faster hasn't proven true in practical application. Watch some of the racers who put ballast in the rear of the car and pick up ET. It's a function of traction and applying the power to the surface.
O'l Cleeter had to run two 100lb steel plates in the rear of Leroy to get it down the track quick. That was on a trick suspension and money no object setup.

Consider that Leroy is a pile of compromises, and the ballast is beneficial because of an abundance of weight in the front and not a lack of weight in the rear. If they could relocate 100lbs from the front and move it back, it would not be heavier, but it would be quicker. The ballast is a compromise, not the best solution. They also need to make weight to run in classes... the reason the classes are weight based is because the lighter you can afford to be, the faster you are. Now look at what they've done, they added weight to the entire car (the body), they removed the ballast, and it's faster than it's ever been. Now if the class allowed them to be lighter, they'd go quicker still.

For a normal person with a normal budget, the placement of the weight is less in our control and sometimes adding more makes you quicker, but a Challenger is also a pile of compromise and any real racer would rather have a car that hooks at 4200lbs than have to put 200lbs in the trunk.

"Perfection is achieved not when there is nothing more to add, but when there is nothing left to take away" - Antoine de Saint-Exupéry
“Simplify, then add lightness.” -- Colin Chapman

 

[Speedy!]

Fair points and good discussion. I'm not caught up on the latest with the body on Leroy, but last one I saw they kept 100lbs in the back. I was surprised they shoot for a 53% F 47% R weight distribution. Maybe at that level the front lifting becomes an issue?

I tend to think of things in terms of the extreme to help me get my mind around them. What if you theoretically had a car that weighed 100lbs but made 1000HP. Would it hook up? I think no. Having said that I would like to find a way to take 200lbs outta my Demon. Car by itself setup for the track was 4320.

Watching them with Eagle will be interesting. I do kinda chuckle when he goes on and on about how fast that car is, and I think it costs $500K it better be lol.

 

[Jack_Toepfer]

I agree, good discussion. I'm not so far removed from real life that I don't know the benefits of ballast, I totally get it. I've used it myself.

As far as 1000hp @100lbs, all I can say positively is that it has the potential to be faster than 1000hp @ 110lbs. How to make that work down a dragstrip, well that's another problem altogether. 1000hp will generate a substantial amount of downforce or forward thrust depending on the type of engine used. A couple thousand hp has produced a couple hundred pounds of thrust, which in theory would double the available weight for traction, or thrust for acceleration - or both. If it's turbo, you can get even more "weight" by pointing the intake towards the ground to create a vacuum effect. Have your downpipes point up and you're talking about weight on the tires that doesn't appear on the return road scale, but provides considerable downforce on the strip. If 100lbs is dedicated to traction and aero, it'll be pretty quick I think.

Take your example and multiple both by 10.
Now you have 10,000hp and 1,000 lbs... kinda sounds more like a top fuel dragster, right? Now they make a little more power, but weigh about twice that much - because they have to, not because they want to. The wings on those cars produce 5000lbs of downforce, add another few hundred from the zoomies... and you weigh a lot at the big end. Shrink it all back down to 1000hp and 100lbs and there is no reason that couldn't be replicated, at significant cost, but the math doesn't lie.

I understand the power/weight problem, I have a 400hp motorcycle. It could be faster if I did x, y, or z... but it is the way it is.

 

[Speedy!]

Aero and down force are the interesting things when you get to the higher levels. I did see the wind tunnel testing on Leroy with and without the body where they broke down the changes and how that impacted down force. Very cool stuff.

For us in these bricks making them lighter will for sure help. I don't think they go fast enough for down force to make a material difference. I'm going to laser focus on 60' next season and will have to think of anything "easy" I can do for weight reduction that doesn't cost a fortune. Recent track outing was VERY productive. I'll have some updates in my thread this weekend.

 

[GNBRETT]

Im with ya and im always trying to make my shit lighter no doubt but from a dig there is a balance between weight and traction on the street where traction is limited.

Lighter means faster on paper when u do weight vs. HP but thats with a prepped track where traction does really come into the equation. Really light cars have a tough time getting that power to the ground from a dig tho especially when its RWD.

Im just trying to understand where I start tipping over into im making too much power for the street the extra weight is now a benifit so I should stop taking anymore weight out of it. Im trying to understand where that balance is with my Trackhawk if that exists at all or will it being as light as possible be better? IDN?

From a roll it plays less of around role but not from a dig and im referring to small tire cars not ones with giant steam rollers. DR tires cars or similar.

Lighter is always able to be faster than heavier. It's in the math.
Getting the power to the ground is a different science entirely.

 

[SilverBillet]

Subtract 200 lbs from any car . Will it be slower or faster? I always heard one tenth per 100 lbs? Assume the same amount of traction with either weight.

 

[Speedy!]

I don't think you have to worry about removing too much weight from a TH.

 

[Jack_Toepfer]

Im with ya and im always trying to make my shit lighter no doubt but from a dig there is a balance between weight and traction on the street where traction is limited.

Lighter means faster on paper when u do weight vs. HP but thats with a prepped track where traction does really come into the equation. Really light cars have a tough time getting that power to the ground from a dig tho especially when its RWD.

Im just trying to understand where I start tipping over into im making too much power for the street the extra weight is now a benifit so I should stop taking anymore weight out of it. Im trying to understand where that balance is with my Trackhawk if that exists at all or will it being as light as possible be better? IDN?

From a roll it plays less of around role but not from a dig and im referring to small tire cars not ones with giant steam rollers. DR tires cars or similar.

Remove all the weight. If you start to run into traction problems, put a real suspension under it.