Hey guys. I have been into high performance cars for quite a while now and everyone in every bracket talks about weight reduction. I was wondering how much of a difference do you guys think weight reduction REALLY makes. I have known people who have completely gutted their daily driver and have spent thousands on trying to replace OEM parts with lightweight parts. I personally dont think it makes that much of a difference. I mean what is 400-600 pounds going to do for you? Cut your 1/4mi speeds by .2 seconds? Now I can definitely understand how that would be very important to a die hard drag racer, but for a casual drag racer I dont see how .2 seconds is worth it? I mean why not spend the money you were going to spend on weight reduction on another performance mod? Let me ONCE AGAIN say, I understand how important that is to a die hard serious drag racer, I am asking for a casual drag racer who does most of their racing on the street. On a privately owned, closed to the public street of course. Someone who just goes to the drag strip once a month to hang out and gauge the improvements on their vehicle. etc.

I just really wanted to know what you guys thought about that. I mean take me for example, I may go to the track once in a blue moon but I am primarily a person who has their vehicle set up for "street trim". To get the most performance out of it while you are on the street. Is .2 seconds in a quarter mile going to help me much? I think not. Like is a pair of subs and a fiberglass enclosure and the stock wheels on the car REALLY going to make a difference? Either way guys lemme know what you think.

Also if someone has a formula for how much each additional pound increases your 1/4mi time I would be very interested in it. Now I dont expect it to be a scientifically sound formula, just a general idea. Thanks a lot guys.


BTW, if possible please dont just say "Yes it is worth it." Try to give some type of reference or numerical figure of WHY it is worth it. Mathematically how MUCH is it improving your vehicle. Thanks guys. I can get yes and no’s all day long. I would like to also get the logic behind those beliefs.


-Sayajin

 

Is Water Wet?

 

100hp = 0.1 in the 1/4 = ~ 10hp.

It's worth it on stuff you don't have to spend money on (pulling spare tire, removing crash brace, getting exhaust anyway, get a light one, etc.) But putting lexan windows, gutting dash, etc. That's all too much for me. I can spend money and get more horsepower than what would be equal in weight

 

weight absolutely makes a difference, and if you wanna know how much of a difference it makes look at it this way. you asked if 400 pounds makes that much of a difference? do this, add 300 pounds of weight to your car (just tell 3 friends to sit in it or something) and zip around in your car, then do the same without the 300 lbs in your car, youll feel an enormous difference in performance, weight is a huge factor in performance, not just for the drag, but in the track and daily go abouts as well, especially for lightweight 4 cycl bangers

 

think about what you're asking for a second. if you have a 3000lb car with 200hp vs a 2000lb car with 200hp, which one do you think is gonna win? that 3000lb car is lugging around 15lbs per hp, while the 2000lb car is only lugging around 10. it's common sense. lighter is faster. that's why skinny kids outrun fat kids. it also helps the car handle better. im not a drag racer, so i dont know how much time u'll gain in the 1/4 from light weight. but i have heard the saying that losing 100lbs is like gaining 10hp. if you drop 400-600lbs (which isn't exactly easy by any means) consider it like adding 40-60hp. what would 40-60hp do for u in a 1/4 mile?

 

I assume you mean 100Lb? If so I am going to have to agree with you. I can see removing stuff and doing stuff thats not going to cost much, but spending an excess amount doesnt sit well with me.



-Sayajin

 

weight def makes a huge difference, but if you take cost/benefit ratio into the equation then...well i guess it all depends on your budget, try to minimize rotational mass as much as possible, thats the most important weight loss, but if youre on a tight budget, you shouldnt go crazy with the weight modifications

 

I think you mean 100 lbs is equal to .1 in the 1/4

 

Try to keep in mind guys, I am not talking about a 1000LB difference. Of course that is a hell of a difference. I am talking about a 100-400LB difference. I obviously understand the basic mathematics behind it, even a child could. What I am asking is from a cost/benefit standpoint is it a big difference? Not is it a difference at all, is it a SIGNIFIGANT difference for the cost? I mean would you spend $2000 extra dollars ona turbo that was going to give you 15hp extra? Obviously the same car with a 100LB kid and a 500LB kid in it will run different times. I mean does spending $2000 on losing 300LBs in my car justify .3 seconds? Why not spend 2k on a performance mod that will give you .4 seconds?


-Sayajin

 

All that math boils down to this:

10lbs = 1 HP

It's not an exact equation, but it's close enough to consider it pretty valid.

Weight reduction helps in acceleration, braking, conering, and potentially gas mileage (given how high gas costs are, some people care about it).

Unsprung weight reduction, however, can often times provide more of a noticeable difference than weight removed from elsewhere on the car. Lighter wheels and tires in addition to a lighter brake system can show significant improvements in all of the above mentioned areas.

 

yeah, sorry. I was watching tv. 100lb = 10hp.

 

Try no to look at it from strictly a quarter-mile-time perspective.

It's potential in other areas will provide more of a real-world benefit.

 

Yea, I could really care less about the quater mile. I am more concerned about "real world" situations on the street. I mean obviously u would want to remove any excess weight you have, look into signifigantly lighter rims, and a lighter exhaust. But I am referring to taking it way past that. I mean, your calculation is a perfect example . I mean why spend $2000 on a pair of rims that are 12 pounds lighter (if I DID NOT car about looks, only performace. Obviously if you are buying new ones for looks you might as well get the lighter ones) for 1.2HP extra?



-Sayajin

 

Bad example. Lighter rims reduce the unsprung weight and make a MUCH BIGGER DIFFERENCE than just dropping 12lbs on the weight of the car. They allow for much faster acceleration plus all the other things Mike@Forge said...

Also, you say you could care less about the 1/4-mile, but the problem is that you don't have any concept of what .1s means in the 1/4-mile between 2 cars and how that translates to the street. I'll give you one example from this past Sunday. I ran a 12.2, and the supercharged 93 Cobra behind me ran a 13.2...a full second slower. This may or may not seem like a long time (1 second), but he was a good 8-10 car lengths behind me? It's hard to measure such a thing when going 110+ and looking in your rearview while slowing down (and your opponent hasn't slowed down yet). Half a second (.5s) is also a very significant difference between 2 cars in the 1/4-mile if they leave at the same moment. In your case, a big sub box could mean a car length difference on the street.

 

If you spend $2000 on power mods the power will be very noticeable and if you take off 400lbs and you go to a road course it will also be very noticeable. A car with those kind of weight savings would corner like a beast and that would make it alot faster than a car that has the same power and stock weight. The most important places to lose the weight are on your wheels, brakes and suspension.