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Does weight really matter that much?

6K views 36 replies 20 participants last post by  focusmaniaczx3 
#1 ·
Yesterday I hit the 1/8 mile drag strip again. This time, I couldn't go lower than 11.27 (.88 reaction time) vs 10.7X last time. Here's the thing, last time I went to the drag strip I ran without the big-o-wing I have, without the 4 hella lights, no emergency tire, no jack, no nothing on the back (the rear seat stayed there), no tool bag (at least 25 pounds), 15" steelies all around, and myself was approx. 10 pounds less. My best time then was 10.7X with a reaction time of .67X Yesterday, I ran with all the extra lugage (wing, lights, tool bag, electric impact, extra tire, etc), plus the 17" EAP SVT wheels all around. Last time I ran with 91 octane gas (1/4 of tank) and a NOS octane booster. This time I only used 91 octane (1/2 tank). Besides weight, the only difference from this run to the last is that then I had NGKs Laser Iridum spark plugs and the Octane Booster, and yesterday I had E3 spark plugs, no octane booster, CFM udps and MSD cops. So, either my car got slower or weight really plays an important factor. What do you guys think?
 
#2 ·
yes, the extra weight makes a big difference. I think the ratio is you need 10 more HP to move an extra 100lbs at the same rate... or something like that.

the wheel/tire combo could be the biggest difference though, depending on how heavy the 15" steelies are. unsprung weight has the biggest impact on acceleration.
 
#7 ·
yes, yes it does...if you have a 200hp engine moving a 3500 pound object compared to a 200hp engine moving a 3000 pound object....there wont be much difference but the 3000lb will win

+ everything said above me
 
#9 ·
The thing is with wheels is if you run 15's (less weight an rotional mass) you will have a ton of sidewall flex witch's = slow steering reponds (IMO i hate slow steering respond's), if you have a larger rim like 17's or 18's (will be heavy an more rotional mass to move) you will have less sidewall flex witch = quick streering respond's. It really doesn't matter how hard your sidewall is (on a 15" wheel) you will still have a ton of flex because your tire actually pivot's where the sidewall an rim meets.

If you do alot of drag racing, circle track, rally racing i highly suggest a 15" wheel but if you do alot of road racing, autox, moutain racing go with a larger rim for less flex.
 
#14 ·
lol yeah its 1/8 mile..

and like everyone has said (and i said on fj) weight is huge..

i noticed a difference in acceleration going from 23lb 215/45/17 tires to 26lb 225/45/17 tires that are .4" taller.. but i have traction so its a trade off.. next time i change tires ill put on some 215/45/17 star specs and see how traction is with the lighter stickier tires..

but yeah even at my power level i feel a difference. so im sure at close to stock levels thered be even a bigger one..
 
#17 ·
Yeah weight is important. Just do the ricer thing and take out your whole interior. Make sure you take off the shift boot to because that'll save at least -4oz. Take off the antenna because that will cause aerodynamic drag. You'll be in the 9s in the quarter after all that. J/K about all that. Weight is important. Ride light, low and tastefull.
 
#26 ·
You guys got off-topic... soon you will be banned so enjoy your last hours in FF [rofl]
 
#27 ·
basically, take the amount of whp you have, and take the actual weight of ur vehicle w/ you in it and divide by the whp. This will give you your hp/weight ratio. on a stock zx3, of 2550 lbs and 110 whp, you get around 23 lbs/hp. So for every 23 lbs you remove, you gain an equivalent 1 whp. Of course, this is a differential equation, so it varies every time you remove 1 lb of weight, but the concept is sound. If you were to drop 200 lbs, you would gain about 10 whp or so. which does not justify 1 second in the 1/8th mile. I would say that it was something else. don't get me wrong. It played a part, but i don't think it did by the amount of time ur talking. but i dunno, its just my $.02
 
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