Official Grand Am Weight Reduction Thread

Alright guys... I've decided to make an official weight reduction thread. I use to be into weight reduction hardcore back in the day, and sharing all that info to grandamdriver52 got me back into it. So lets think of items and it's weight that can come out of our babies. I'm going along with the general idea that we don't want our cars looking like gutted drag-cars, so I'm gonna stick with generally not effecting appearance too much, but feel free to post up anything that will save weight. Oh, and I'm only gonna be posting free weight reduction, because I'm a starving (soon-to-be) college student, obviously :smokin: - So... let's "add some lightness"! I'll start:

steel plates in doors (2) - 4
intake resonator - 2
stock airbox / ramair shroud when upgrading intake - 6
childseat anchor plates (2) - 15
sound deadening - 20
tar mats / fiberglass blankets - 20
Spare tire (doughnut) - 30
Spare tire jack - 15
Rear floor mats (2) - 4
Front floor mats (2) - 6
A/C - 35
Back speakers (2) - 15
Front quarterpanel spkers. (2) - 10
Useless shit in trunk that you probably have in there - 10
Useless shit in console / glovebox that you never use - 5

Ok, so far that's roughly 135 pounds

Hey Ride,

The one thing you forgot...Have the driver evacuate prior to getting in the car...HAHAHA.
Just kidding.

Thank you for the list I'm sure it will help a lot of people making the cheapest mods possible. In today's economy every penny saved will help with wirh the costly nods.

Thanks again,
Dan

Gotta add going to acrylic or lexan windowsI figured out I could shave almost 200lbs if I convert all my windows, we have a supplier at work that converts all are heavy equipment so I'm in the works of figuring out prices, so far I could probably have it done for under a 1000 bucks based on what we get charged. Real cool!!!

Marc

how bout the hood? Is there a replacement carbon fibre or fibreglass? And does anyone know how much they weigh?

Spare tire around my waist - 35lbs

Wow that'd be pretty good!!

so how much does the weight reduction reduce lets say the 0-60 times just rough guess, oh yeah the back seats remove and install really easy in my 99 if you dont plan on an passangers

Hey Ride,

The one thing you forgot...Have the driver evacuate prior to getting in the car...HAHAHADan

LOL :) So true - take a run to the bathroom, and don't wear any clothes or shoes - that's about 10 pounds right there!

Marc, you gotta keep us filled in on the windows - 200 pounds is great

Frekey, yeh there's a couple hoods available.

www.rsmracing.com
www.pfyc.com - i think has another carbon fiber
www.rksport.com - has a carbon fiber I'm pretty sure

most carbon fiber or fiberglass hoods will save you roughly 40 pounds over a stock hood

and here's an interesting site I found with a bunch of fiberglass parts - made for our cars for track cars - i think most of them could be made to work with ours; check it out

http://www.vfnfiberglass.com/0102grandam.htm

LoL muzzy maniac - yeh deffinately weight reduction can start with one's self :) - some people could easily save 100 pounds right there

wasn't there a post on here asking about racing seats and a different roof? I thought I saw it, but it seems to have been deleted. Well I was going to say, sparco and some other companies make great racing seats for our cars, and you'd be saving about 25 pounds each, for 50 pounds total. The only problem is that a set usually costs 400 to 600 $$. LoL. And as far as the roof, that link I put up above might work for that - you could get a fiberglass roof from them - and that's where it matters most - weight way up there can dramatically affect your handling.

Ok, so between the windows, the hood, and the racing seats, the back seats (20 pounds mcbeefer) that's another 310 pounds. Added to what I said earlier, that brings our grand total of lightness-adding up to 445 pounds! :) Keep it going

Oh yeh, and to answer your question Mcbeefer, I'll do my best. Ok, this is going to take a little bit of math. My car right now runs 15.5 1/4 mile @ 87 MPH , and 9.9 1/8 mile @ 71 MPH. Using the 0-60 calculator here http://www.sjdsm.com/tech/0_60_calc.htm, and timing it myself my car has ran almost exactly 7 seconds 0 to 60 every time.

So, if we say that removing 300 pounds from my vehicle as-is will bring my 1/4 mile time down to 15.2, (assuming that 100 pds is good for about .1 sec, general rule of thumb on cars our size), we can say that the ratio of my 1/8 mile time to my 1/4 mile time will stay the same. So 9.9 / 15.5 = 0.638. So keeping it proportionate, if my new 1/4 mile time with the 300 pound loss is 15.3, then my new 1/8 mile time would be roughly 9.76. These calculations are all very general obviously, as they don't account for such varying factors like different exponentially changing drag coefficients, different gear ratios, launch spin, air temperature, ect. There's just too many variables to make a precise calculation. So, using our new 1/8 mile time of 9.76 on my vehicle after the 300 pound loss, and plugging the numbers back in, we would find out that the 0 to 60 has gone from 7 seconds to roughly 6.25 seconds. So on our cars, with all the factors roughly considered, a 300 pound loss would decrease the 0 to 60 time by 0.75 seconds.

That same rule of thumb also states "every 100lbs shaved is the equivalent of gaining 10hp". So it would be like gaining 45HP! In theory it would be as if my little 2.4 was pumping 195hp! And yes I'll keep up to date on the windows.

Marc

Sorry, guys, I just can't resist!!!!!!!!!!!

Stop driving the g/f around!!!!!!!!!

LMAO

HAHAHA! That's funny because I told my wife that I am no longer letting her friend tag along 'cause I lose 25hp and she upsets the balance of my car. That was really mean of me, but she's a bitch. So I don't feel to badly. Actually I have a harsher name for her but I'll refrain...

Side note: Usually I'm not this cruel and I know "if you don't have anything nice to say then don't say anything", but this girl has done some awfull things, I keep telling my wife to dump her from the "friends" list, but my wife is just to damn kind. So please don't judge my character.

LOL Marc

LOL! :) OMG I totally hear you guys! I was giving one of my (girl)friends a ride in my car a few months ago, and then another one wanted to come too, so I let her sit in the back, but I told them "you know... you two are killin my power to weight ratio" and then they asked what that was and I had to give them a very basic rundown of the basics of physics - and I took them both for a ride none-the-less, and lemmee tell ya, with about 300 pounds extra of woman-flesh in my car, my acceleration sucked! LoL - that was a great line to use Marc. Next time anyone I don't like wants to ride with me, I'll just do the mental math of their weight, and tell them roughly how much HP I will be loosing because of them :)

It's true! It's like my car still accelerates pretty good when it's just me and my wife (she a thin girl), so I can handle that... But her friend weighs 250lbs. I tell ya if she had more friends like that and I had to give em all a ride, I'd have like.....0HP

This is turning into a bad thread....see what ya started Knifeblade :disappoin. You took ride's perfectly innocent thread and turned in to this, eh, come on now...:thumbsup:LOL


Marc

Run on a 1/2 tank of gas or less. I know water runs roughly 8lbs per gallon so I figure gas should be pretty close behind. That should knock off say 40lbs...?

LOL yeh no kiddin tam, you bastard! :)

Yeh muzzy, gasoline does weigh a lot. It's actually 6.7 pounds / gallon, so a 1/2 tank in my car is roughly 50 pounds. I try to run it 1/4 to 1/8 tank if I know that I'll be racing, other then that, I try to never really fill above 3/4.

I track my fuel mileage so I have to fill it up otherwise I don't get an accurate reading. I currently average 11.61L/100KM, or 24.33M/IMPG (Canada). 20.26M/USG for you US guys. Damn I'm anal.

Marc

LOL, Marc, no ya not, I compliment ya on doing the math conversions, metric always confuzled the hell outa me when converting to US, and let's not EVEN go there with socket sizes, LMAO.

LMAO, hey this was all about weight reduction, and passengers are added weight, and the loss of the weight adds to HP, so I stand innocent, heehee.

One thing no one seems to mention is the wheels, ya can save at least 40 lb.'s over stock rims by going billet all around, and that is at the ground which has to add an incremental boost due to lack of inertial force [weight] to get the tires moving, I think.

>snip<

Next time anyone I don't like wants to ride with me, I'll just do the mental math of their weight, and tell them roughly how much HP I will be loosing because of them

>unsnip<
Well, that seems one very polite way of saying to a woman she is too heavy, :rofl:

I in a mood, so excuse the flippancy, guys.

LoL yeh it is tough to say to them without making them think they're fat. What I've said is always underestimating - say they look like they weigh 150, I'll be like "...sayin you weigh about 130, that'll be a cost of about..,..." - LoL it's a zinger :)

Lol :biggrin:

Remind me never to hitch a ride with you guys :/

LoL. Hey I've got some great news (I'll get pics up soon). On the topic of weight reduction, I just got an incredibly badass S/CT hood for free. Not only do the open scoops help get cooler air to my intake, but the hood feels at least 15 or 20 pounds less then my stock one. It's so awesome. I swear my car handles a little bit better too cause that's a decent weight drop for up on the front end of the car where it matters most. I am VERY happy - I just put it on tonight, and it looks so badass, and was great driving :)

Thats awsome. How did you get it for free?

That's pretty sweet, Ride. Oh yeah, I looked further into the glass issue. My supplier will hook me up for just under CDN$1000, and they'll use the spec'd templates for my car to cut them for me! They're Lexan weighs 1/4 the weight of automotive glass and is a hell of a lot stronger and they said my wipers won't damage it.

I figure auto glass: Windshield-80lbs, Rear window-100lbs, Front door windows-50lbs ea, Rear door windows-40lbs ea, 1/4 glass (rear doors)-5lbs ea, Total-370lbs

If lexan is 1/4 that of glass:92.5lbs total.

Weight saved 277.5lbs. That's like gaining at least 25HP!!! Not bad for a grand.

Marc

Marc, just curious, is the Lexan glass mod. ya mentioing pretty good at resisting scratches, or will there be some future problem with hazing or dulling so visibility gets bad?

Holy shit marc, that will kick serious ass! 277 pounds saving just off of glass alone!!! - Good lord!! :):):). You will TOTALLY be feeling that difference.
And to explain my hood, grand am driver, just go check the off-topic thread in our forum - I posted the whole story and some pics.

I still say dump the g/f to ride around with, so ya can pull up to my beater '89 eagle Premier, and try to show what ya have off the line, LOL, LOL, trust me, it is a screamer, though not like the GA at rpm's, but I've dusted my share of GA's with the Eagle.

hey burnin half of your tires should save on weight...lol

LoL oh no kiddin - rotational mass is a biggie! :) - not only that, but burn em down enough and you'll have made yourself a set of street slicks, which will help a shitload with launches! :)

Oh, and tam, I believe you when you say your eagle is "a screamer". LoL

Ptttttttthhhhhhhhhhh :nono: :lol:

One other thought, remove the power sunroof motor and stuff, leave the glass alone, that saves a few lb.'s

Yeh the motor would be probably 5 to 10. Wow, I had my whole sunroof assembly and glass out back when we redid my car, and I swear that thing must've weighed at least 40 to 50 pounds.

wow, thats quite a bit of poundage. thats one plus of not having a sunroof, i always wanted one but i guess not so much now.

One thing no one seems to mention is the wheels, ya can save at least 40 lb.'s over stock rims by going billet all around, and that is at the ground which has to add an incremental boost due to lack of inertial force [weight] to get the tires moving, I think.


Will Yugo wheels and tires work?? LOL!! Small, thin, light - I like it. It should also add to that "just lowered" look too.

Marc, just curious, is the Lexan glass mod. ya mentioing pretty good at resisting scratches, or will there be some future problem with hazing or dulling so visibility gets bad?


One price to the weight reduction by going to lexan is that it is higher maintenance than glass. You can't use certain cleaners on it or it will discolour but you can use your wipers. There is a special compond you can put on it to protect it also.

Here's my Pro's/Con's list

Glass: Pro;Does not scratch easily (major benefit in winter due to slush, sand and road salt),

Con; Heavy, easy to break thus easy to break into, expensive.

Lexan: Pro; Very light (1/4 the weight of glass), Very strong (250 times more impact resistant than glass, basically your car will never get broken into by smashing a window and debris on the highway will not go through your windshield including Deer :) ), Same price if not cheaper than automotive glass, up to 8 times more clear than glass

Con; If your out camping don't lock your keys in the car or you're F*cked, Higher maintenace because it is softer than glass (this is where a lot of the impact resistance comes from), Shorter life expectancy than glass under same driving condition (sandblast effect from road dust), Certain glass cleaners will harm lexan, windshield must be wet (should be wet) before running wipers, deep scratches (like a rock nailing the windshield could be too deep to buff out (although minor scratches can be)

I personally feel going lexan is the best choices if you are looking for performance, but if that isn't a concern I would probably lean towards glass because of the lower maintenance.

Marc

1 pound of rotating weight = 7 lbs of static weight. So taking 40 lbs off the wheels = 280 on the chassis.

Thanks for reply,Marc, gives something to think about.

Elk, ty for the math, I had kinda thought there was something incremental that would be beneficial by lowering rotating mass over just the static weight. Cool!!!

LoL yeh muzzy, yugo wheels would do the trick :)

Marc, great break-down. THat makes me REALLY want Lexan, damnit!! :) lol

elk, I wonder if that's just tires? I heard that 1 pound of rotational mass was equal to 10 pounds of normal (unsprung) weight. That may have been referring to actual engine / drivedrain components though, instead. I suppose these numbers are very general rule of thumb, however, as there would be a huge amounts of factors to make an accuracte statement.

Excuse me fellas, I'm relatively new to these forums, (not new to forums in general, or cars), and I've been reading about your weight reduction, supposed horsepower increases, and fat girlfriends (sorry no offence there, lol). BUT, something has been on my mind. I know it's just a general rule, but your car will never really act like it has increased a specific amount of horsepower due to a drop in a specific weight, because any drop in weight is a percentage of the total weight of the car. I'm using kilos here cause I'm not used to pounds, but if a car weighs 1500 kilos, and you somehow drop the drop 500kg for arguments sakes, you've dropped the weight of the car by a third, and increased it's power to weight ratio by 33%. On the other hand if you do the same thing to a 1000kg car the end result is a 500kg car (unrealistic, but still feasible) and have increased the power to weight ratio by 50%. Lets imagine these cars both have 500hp. In these cases, the 1500kg car will behave like it has increased 250 horsepower, and the 1000kg car will behave like it has increased 500 hp to achieve a 1kg to 1 hp ratio. Thats my point. Please provide feedback and opinions.

Just another quick illustration, imagine you have a 200 pound buggy, and you can run the quarter in 16 sec. You then half the weight of it, you drop 100 pounds which is supposed to drop your quarter time by .1. Halfing the weight of this buggy will most likely make you run like 10's or something with the same power output. All's I'm saying is that it's all relative to the actual weight of the vehicle, more accurately as a percentage.

Alright I've read enough. you guys just don't get it. As far as I see it you have two major weight reduction options:

First: For you guys running the V6's all you have to do for an approximate 30 to 40 pound weight loss is to cut off your left arm and leg, you dont need them any way, you do every thing with your right side any way.

Second: To increase your 1/4 time and gain an average of 148 pounds...get up to the line put a 2 pound btick on the gas pedal and on the green jump your ass out of the car... LOL

Just a couple of jokes guys. I have read this whole thread, and I mean read the whole thing [I don't want to be accused of not reading]. I think you guys have gone over the edge, it is one thing to be a Technomod (thats for you Ride), but to take a car that actually your mode of transportation and spend all that cash to make it lighter is a waste. Take your cash and invest in a real race car, I would go entry level PRO STOCK for around $150,000 for a chassis and composite shell. That way you will not have to worry about the girls and how much weight to accelleration ratio will effect the bottom line.

Hey DO NOT take the above seriously, I'm just having some fun. I did read the thread and some of the ideas sound as it they will peoduce some very favorable results in the quest to reduce the overall weight of the car. I do have one more serious comment: Do not forget...you can take off all of the weight you want and develop the fastest car on the road but if you don't have the skills to drive you can race all you want and never pull the checkered flag.

Just havin fun with you guys,

Be cool, guys!

True, it is a power to weight ratio issue. And the rule of thumb is based on exactly that, rule of thumb. The "100lbs is worth a tenth" is a starting point. Weight reduction will not make a car faster (top speed) only quicker at getting there. To make a car go faster without physically increasing the engines output you have to change it's CD (coefficient of drag). That's why a 140HP "crotch rocket" can do 160Mph while a Corvette needs 400HP to do the same thing. And if anyone is considering going to a crotch rocket: I've driven one at a measily 150KM/hr and I've driven a ZR1 Vette at 250KM/hr, the vette leaves less of a skid mark in your shorts... LOL
Hey Hoags, If you went to "Hand controls" for throttle and brake you could even cut off the right leg :O LOL

Marc

Good point Marc, but then you will not realize the full weight loss of the right leg due to the added weight of the hand controls.

One additional comment about the crotch rocket theory, there is also less mass weight of the rider because he has to be a little light in the head to go that fast on one of those things!! LOL.

LMAO, true true. I was watching "Top ten speed machines" on the discovery channel and they showed the Suzuki Hayabusa (world's fastest massed produced sport bike, 190Mph) which was completly insane!

I'll stick to my 90 Kawasaki KDX200 dirt bike, and I'll keep to the trails.

190mph, What the HELL for????

From what the show was saying it was a battle of the Japanese motorcycle companies to build the fastest bikes. Once the hayabusa was produced they all made packed that the bikes were getting too fast "Regular" customers and decided too stop the "the speed war" and keep that stuff for the race tracks. It still stumps me though cause most of those bikes that are made now are still very fast. Any newbie buying one is still not going to be able to handle them safely at high speeds without proper training. My 2 cents

Marc, I'm going to move my comments over to the Off Topic Thread. I'm sure other members will want to chime in on our conversation. Check it out if you want I do have a comment to make.

I think we have jumped too far off the track for this thread.

See ya on the other thread,
Dan