Weight obsession - part weights on S13

[kognition]

Agreed,
It is far far easier to add horsepower with all of the options available to us than waste time cutting away at an allready very lightweight chassis shell. I have learned from real world experience that you can effectively control horsepower with a good downforce setup.

Originally Posted by fckillerbee

100 lbs is 9 horsepower...i'm sure all of us have heard this....and it all adds up.

so instead of removing shit....add power! haha.

[SoSideways]

Well, lightweight benefits the car in braking and handling as well, and given a set of tires in one size, the lightweight car will be able to use that tire better than the heavier car with more power.

But I also agree that there comes a point when there's diminishing returns when you do something like lightening up the car and stuff.

[Corbic]

Originally Posted by fckillerbee

100 lbs is 9 horsepower...i'm sure all of us have heard this....and it all adds up.

so instead of removing shit....add power! haha.

Hence why HR 350Zs spank AP2 S2000 ass all day long both on and off the track.

[Def]

I don't think there are diminishing returns at all, in fact, the returns INCREASE as you keep shedding weight. 30 lbs off a 3500 lb car? Not a big change, only 0.85% less weight. You would probably be hard pressed to really feel that. Now 30 lbs off a 2500 lb car, that's 1.2% less weight. 2000 lb car? 1.5% less weight. So it starts to become more and more apparent for each pound you lose as your car gets lighter.


I'd rather spend money on track time and tires at this point than buy other stuff, so I'm going to see how far I can really go with the stock panels while not making the car significantly less safe in any one type of impact.


Looks like lexan rear hatch window, remove as much weight as possible to the doors while keeping some crash protection, and then attack the rear bumper support.

[racepar1]

Originally Posted by kognition

I have a bare S14 chassis in my shop with roof cut, subframes removed and all suspension/ fuel tank/ engine gone. I can lift the thing up with very little strain.

On this note, 5 guys can easily carry a bare fastback chasis with a cage and quarter windows in it. When I got rid of my fastback we picked the shell up off the jackstands with 2 guys on the front and 3 on the back and carried it to the trailer. Eric Castro's got it now...

[Corbic]

Originally Posted by fckillerbee

100 lbs is 9 horsepower...i'm sure all of us have heard this....and it all adds up.

so instead of removing shit....add power! haha.

Originally Posted by Def

I'd rather spend money on track time and tires at this point than buy other stuff, so I'm going to see how far I can really go with the stock panels while not making the car significantly less safe in any one type of impact.


Looks like lexan rear hatch window, remove as much weight as possible to the doors while keeping some crash protection, and then attack the rear bumper support.

But you are agreeing with him.

What will make a bigger difference, saving 170lbs by getting a FRP Hood, Fenders, Hatch, doors and gutting the interior.. For ~$2000....

Or upgrading your turbo/powertrain and go from 200whp to 400whp, or maybe just 300whp and some bigger brakes?

What will do better a stripped car, or a car with cage and bracing (adding weight) but all else equal.

Also, the diminished returns are lik FRP fender, cost? Over $300, easier to damage, and you shed maybe 5-10lbs. ~1hp gain.

If I said I just spend $300 on an airfilter to gain 1hp everyone would laugh.

[SoSideways]

Def, your points back up my points exactly.

There comes a point when you're spending ridiculous amount of either money, effort, or both, just to save very little weight, or to make that last 10hp, either of which won't make any real difference in the grand scheme of things, except for you to be able to say you did it.

While I agree, technically, there is no diminishing in returns when you're talking about saving weight, but there certainly is a diminishing in returns for the path to get there.

[racepar1]

Let's stop this "more power vs less weight" crap. Reducing weight makes the car accelerate, stop and handle better. It improves the car in every possible way. More power only makes the car accelerate better and it can make the car HARDER to stop and turn. Reducing weight also takes strain off the entire drivetrain and chasis, which increases reliability. More power does exactly the opposite. Besides all that a more powerful engine usually comes with a shorter lifespan and less reliability again. Horsepower is great and all, but reducing weight serves a completely different purpose. The two cannot be compared as their performance benefits are only similar in one aspect.

[godrifttoday]

Why not redo all your wiring I know it's like 50 ponds, get it down Into 10 pounds, u can also Lose weight

[josephin510]

Originally Posted by racepar1

Let's stop this "more power vs less weight" crap. Reducing weight makes the car accelerate, stop and handle better. It improves the car in every possible way. More power only makes the car accelerate better and it can make the car HARDER to stop and turn. Reducing weight also takes strain off the entire drivetrain and chasis, which increases reliability. More power does exactly the opposite. Besides all that a more powerful engine usually comes with a shorter lifespan and less reliability again. Horsepower is great and all, but reducing weight serves a completely different purpose. The two cannot be compared as their performance benefits are only similar in one aspect.

Just as I was getting confused you posted this.

[GripTerror]

Originally Posted by racepar1

Let's stop this "more power vs less weight" crap. Reducing weight makes the car accelerate, stop and handle better. It improves the car in every possible way. More power only makes the car accelerate better and it can make the car HARDER to stop and turn. Reducing weight also takes strain off the entire drivetrain and chasis, which increases reliability. More power does exactly the opposite. Besides all that a more powerful engine usually comes with a shorter lifespan and less reliability again. Horsepower is great and all, but reducing weight serves a completely different purpose. The two cannot be compared as their performance benefits are only similar in one aspect.

This

Fuck racepar1... you and I share the same mind... from reading many of your posts over and over again haha...

Kognition also has a point but I must concur racepar1's points hold truer. I mean... alhtough it is not too hard to add power, the benefit of less weight although sometimes painstakingly ass paining are beneficial in a multitude of ways That is if you are serious of cutting every tenth of a second on lap times...

Oh and for people saying panels are only 1lbs or whatever... well... I went pretty hardcore on my car's diet and I easily took off 300lbs and that's on a car that had no AC... it's doable...

Remember he also has a cage, so that's added weight back.

I even went as far as cutting unecessary wires from the wiring loom (speaker lines, etc...) and only left what's necessary. Got rid of all the under dash crap (heating, cooling, etc...), so yeah... if you want a hardcore track car go the mile... my opinion... and add downforce and im sure kognition can help lol.

Trust me.. the more weight I lose the more pronounced it feels on the car over time.. it just does.. and it makes the car that much more fun to me.

[Corbic]

But after all that work, how much did your track times really improve? Or does it just "feel faster" and "more responsive" because of all the extra road noice and drive train vibration?

350z HR weight 3,339#, HP 306hp, 268 FT/TQ

AP2 S2000 weight 2,765#, HP 237hp, 162 FT/TQ


Despite having lighting fast reflexs and a feather light chassis the S2K is sorely beaten by the 350Zs power and stiffer chassis in several comparisons, (I'll post YouTube vid latter).

[Corbic]

Originally Posted by GripTerror

This
Trust me.. the more weight I lose the more pronounced it feels on the car over time.. it just does.. and it makes the car that much more fun to me.

Feelings are for girls, facts are for men.

Is it "that much faster" or just "that much noisier"?

[SoSideways]

Originally Posted by Corbic

Feelings are for girls, facts are for men.

Oh no you didn't.

Watch out man, he works out, and makes fun of people who have powersteering because he can turn his 330mm steering wheel with just 2 fingers.

[Corbic]

Originally Posted by SoSideways

Oh no you didn't.

Watch out man, he works out, and makes fun of people who have powersteering because he can turn his 330mm steering wheel with just 2 fingers.

I hear he has a terrifying grip.

[xpertsnowcarver]

I'm in at 2280 without me in it. About 5/8 tank of fuel.

The car is pure fun. XD Don't really car about power, I just want my fun.

[DJPimpFlex]

Originally Posted by xpertsnowcarver

I'm in at 2280 without me in it. About 5/8 tank of fuel.

The car is pure fun. XD Don't really car about power, I just want my fun.

Have you ever driven a car with power? I just did my first full track with 280wheel and its the best thing since sliced bread.

[Def]

Originally Posted by Corbic

But you are agreeing with him.

What will make a bigger difference, saving 170lbs by getting a FRP Hood, Fenders, Hatch, doors and gutting the interior.. For ~$2000....

Or upgrading your turbo/powertrain and go from 200whp to 400whp, or maybe just 300whp and some bigger brakes?

What will do better a stripped car, or a car with cage and bracing (adding weight) but all else equal.

Also, the diminished returns are lik FRP fender, cost? Over $300, easier to damage, and you shed maybe 5-10lbs. ~1hp gain.

If I said I just spend $300 on an airfilter to gain 1hp everyone would laugh.

I'm probably in the low 300's on track at low boost(14ish psi on a GT2871R, cams, intake mani, ported stuff etc.). I could turn the boost up, but I have my doubts as to how long the stock engine will last, so I'm keeping it reasonable for now.

More power is a turn of the knob away, but it's not really needed since the street tires hold the car back more than power at this point.

Like I said again, I'm not interested in spending $$$$$ on some FRP panel to save 10 lbs at this point. There are other areas where I could save weight for very little $$$, so that's why I asked about the items I did.


I have racepar1's ideas on weight reduction, when you on the track, every pound off the car just makes everything easier on the car. You accelerate harder with the same power, brake faster for the same traction, corner harder - it just makes the car easier to get around the track, and it becomes even more pronounced when you add downforce(which I already have, check the earlier track pic).

[roboticnissan]

If vgetting the car down to a specific weight becomes to costly or just a pain in the ass, then that's your limit.

What it comes down to is how far YOU really wanna take it, or how seriously competitive you really wanna make your car. If you seriousy wanna win every race in your class then EVERY pound is going to count.

Hope this makes sense

[xpertsnowcarver]

Originally Posted by DJPimpFlex

Have you ever driven a car with power? I just did my first full track with 280wheel and its the best thing since sliced bread.

Yup. That's me in a 340whp 180sx. (No aero on this car.)

I can honestly say it's not as fun as my NA car. (No aero on this car either.)

Maybe if it had amazing down force (ahem... Kognition ), it could be a bit more fun. I can't say much, nor could a lot of us.. Most of us do not have highly engineered aerodynamics on our cars. No doubt a high horsepower car with well engineered aerodynamics would be very fun.

I'm strictly talking about a realistic observation of the average individual owning a 240sx... Not many can afford to put a 300whp 240 together AND get some serious down force. So, its cheaper to cut down on weight. It benefits in all categories. By the time most of these people can afford to modify the car to get serious power and downforce, they probably move on to better things anyway.

Regardless, weight reduction is pretty critical. Maybe not so much for minimum weight cap regulations. Then, its critical for equal weight distribution, downforce, and power.

Ugh, I think I'm biting more than I care to chew right now. I withdraw from this. Mike knows what he's talking about anyway.

[reflexdb]

S14 chassis with S14 SR20. No power steering, no HVAC, no interior except for seats, dash, center console, door panels, harness bar, and bare minimum wire harness. With full fluids, it weighs in at 2370. Really, there isn't a whole lot more weight to pull out of it without getting Kognition-extreme.

And I agree with anyone that supports minimizing weight. Your car is going to handle better everywhere on the track if you shed some pounds. Of course, increasing engine output will make for quicker acceleration too (assuming you have enough grip to transmit the power to the road). There's a reason why power/weight ratio is one of the most important performance comparison factors.

[Corbic]

As promised
YouTube - Nissan 350Z 2007model VS. Honda S2000

350z best lap 1:07,63
S2K best lap 1:09,17

YouTube - The Ulitimate FR Challenge Z33 vs. S2000 - Hot Version International - 1/2
YouTube - The Ulitimate FR Challenge Z33 vs. S2000 - Hot Version International 2/2

[Def]

That's not really that big of a surprise in stock form, as the S2000 understeers a bit in AP2 trim and is pretty slow compared to an HR Z33. That 1.5 s difference is almost completely up to power differences.

[Def]

^Just watched the videos. Of course a modded NA Z33 HR will make boatloads more power than an S2000. It looked like the S2000 handled a bit better from apex speeds, but the Z33 would just pull out from there.

[mattsil80wis]

Originally Posted by xpertsnowcarver

I'm in at 2280 without me in it. About 5/8 tank of fuel.

The car is pure fun. XD Don't really car about power, I just want my fun.

info on what you lost to get down that low?

edit: if you dont want it on the board do you mind PMing me

[Jonnie Fraz]

I am waiting for Bill to jump in on this one...lol

[WangonwWarrior]

Z32 aluminum uprights weight 7-8 lbs. less and that is unsprung weight on the rear



Im about to do mine. Only problem is you will have to use a fork type rear strut like the Z32 or you can weld on a different top piece

[kognition]

I hear what you guys are saying about removing as much as possible. From my experience, the lightest car does not win championships. The most well balanced and consistent car does. And i am just as passionate as the next guy about weight reduction. But unless i see you out there winning contingency money with it, it doesn't mean much. It is just one of many aspects. It isn't rocket science. Once you are happy with your chassis stiffness/weight, you move on to the other areas that need attention. When i started working with World Racing on the super light AWD car, we were all excited for the debut. I flew all the way to Sebring just to support the car. The car sat all weekend due to electrical gremlins. They put alot of work into weight reduction, and spent tens of thousands on hauling a fully staffed crew and rig out there. It is a half a million dollar car! Kognition has two championships allready in the bag with two sponsored time attack teams this season. They are not the lightest nor the most powerful cars in their class. And certainly not the most well funded. They are the most balanced, and consistent cars in their class.

[godrifttoday]

^
it could be also driver.

And DEF

Dammmmm u got major credibility !!! U post something and u get thousand of views to read your words!!! major pull....

[DJPimpFlex]

Originally Posted by xpertsnowcarver

Yup. That's me in a 340whp 180sx. (No aero on this car.)

I can honestly say it's not as fun as my NA car. (No aero on this car either.)

Maybe if it had amazing down force (ahem... Kognition ), it could be a bit more fun. I can't say much, nor could a lot of us.. Most of us do not have highly engineered aerodynamics on our cars. No doubt a high horsepower car with well engineered aerodynamics would be very fun.

I'm strictly talking about a realistic observation of the average individual owning a 240sx... Not many can afford to put a 300whp 240 together AND get some serious down force. So, its cheaper to cut down on weight. It benefits in all categories. By the time most of these people can afford to modify the car to get serious power and downforce, they probably move on to better things anyway.

Regardless, weight reduction is pretty critical. Maybe not so much for minimum weight cap regulations. Then, its critical for equal weight distribution, downforce, and power.

Ugh, I think I'm biting more than I care to chew right now. I withdraw from this. Mike knows what he's talking about anyway.

I suppose we are speaking a different language because I think your grip driving while I'm drifting. I've griped my car a few times and its, well, stressful, lol. Street tires and my suspension set up makes the car very oversteer prone so I end up going a bit slower than I could. I agree that a N/A car with low power is a lot of fun to grip, its just been awhile lol. I've been drifting only for a few years now.

Either way I try to reduce as much weight as I can. I alter the set up based on what I feel the car needs and run it. I'm by no means a great driver but I feel like my car is pretty well set up.