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72BBSwinger
03-17-2015, 12:07 PM
Really curious what guys are ending up with for weight bias, front to rear, with the awesome builds this site has on it. You guys with wagons, LS anythings, 4 doors etc. I would love for you guys to share what you're at with what if you've scaled your cars. I haven't scaled mine since it isn't rolling again yet, but will SOON. I picture this as a:
1970 Chevelle
LS3/T56/Ford 9"
weight: 3650lbs, all steel, 1/4 tank of fuel, no driver
Wheelbase: in inches
bias: 58/42 f to r.
I think ALOT of you builders know this stuff about your own car of others you have built, please share. Would love to know Kyle and Stacy's cars' specs, 48 Camaro/Vette, Ring Bros etc.

cornfedbill
03-17-2015, 12:37 PM
I have a '74 Nova hatchback. It was not bad from the factory. I moved the front axle forward 2 inches, will be moving the rear axle forward 1 inch, moving the battery to the rear, and will be replacing all of the front sheet metal with fiberglass (hood, and inner and outer fenders). The front bumper shocks are going away as is much of the front bumper itself.

The goal is 50/50 weight bias with a small block. We will see how it goes.

The calculations show it is possible. Time will tell.

72BBSwinger
03-17-2015, 03:35 PM
What wheelbase is the Nova? My Dart is 111" and the post cars,Dusters/Demons and A body Barracudas are 108".

cornfedbill
03-17-2015, 05:40 PM
Same as your Dart, 111 inches. It will be 112 when I am done. I would prefer to make it shorter, but conflicting goals didn't favor that.

72BBSwinger
03-17-2015, 07:50 PM
Mine is more than likely closer to 110 with the amount of caster it has in all honesty. If my driveshaft was short enough I would move the rear forward an inch simply by drilling a new center pin hole in the main leafs.

SSLance
03-18-2015, 04:09 AM
I'd have to check my notes but off the top of my head I'm at 57F,43R and 108" wheelbase.

I'm rearranging a few things inside the car and once done I'll weigh it again. Hopefully it gets a bit lighter and a bit more is moved to the rear.

Matman3
03-30-2015, 03:51 AM
I'm at 51F/49R weighing in at 3178lbs in my C4. I was able to move around some weight and take some off to get this balance. I like the handling balance with this combination.
Talk with a local race team and have them scale your car. I was able to spend a day on the scales experimenting with different weight combinations and locations to see what worked best for my application.

72BBSwinger
03-30-2015, 10:21 AM
I guess another thing of note is simple weight changes like, is battery in trunk?

Matman3
03-31-2015, 03:11 AM
I took quite a bit of weight off the front end which helped quite a bit moving the weight bias rearward. That's not all I did but that yeilded the biggest return. Lightweight wheels have a huge effect as well. I saved 9 lbs per wheel just by replacing the factory wheels with aftermarket. I wish I could say I planned it that way but I was just looking for a good looking wheel and got lucky.

nokones
04-01-2015, 06:05 AM
My 89 C4 Corvette is 49.6%F/50.4%R and cross weight is 50.0%, leftside is 50.7%, and the car weighs 3008 without the driver and only a couple gallons of fuel. The cross weight and front/rear bias was with driver's weight in the car. My ride height is 4 5/8" RF, 4 3/4" LF, 4 11/16" LR, 4 1/2" RR. All 4 corners are adjustable on my car.

Note: Do not attempt to adjust your car to my specs to achieve a 50% cross weight because you will never achieve that goal. Not every car is produced the same. You may find that your car's roll center is an inch from one of the corners and/or 10 feet in the air.

If you cross weight your car, make sure that you disconnect the sway bar(s) and add driver's weight, the appropriate amount of fuel you run with, and don't forget your tire pressers. I can run an autocross with only a couple of gallons of fuel. Of course, I have to add a gallon between each run.

Arrowhead
04-01-2015, 11:52 AM
Ridetech has a pretty awesome database of vehicle weights with front/rear and drivetrain setup if that helps

http://www.ridetech.com/info/coiltech-2/

Tomswheels
04-01-2015, 09:21 PM
1967 Valiant 2DR. All stock metal body panels and glass, with all seats and a roll bar, fiberglass front bumper, full tank of gas, heavy 18/19 inch wheels, all iron small block, aluminum 4spd trans... 3250lb. I was hoping for lighter....

Dr G
04-30-2015, 01:44 PM
This is for a 1956 Ford F100. It is about to undergo a major transformation. You will understand if you look at the corner weights, I think the original builder may have built a twisted frame, I'll find out when I get it fixtured up.

https://static1.pt-content.com/images/pt/2015/04/original20corner20weightsM-1.jpg

56/44 front/rear

I plan to build a new frame and move both axles forward 1.5"

The front axle was already moved forward about 2-3" with re-profiled fender openings. I also plan to shift the engine down and back relative to where it is now. The original builder put his own subframe right in the way preventing the engine from going anywhere near as low or far back as it could (should).

72BBSwinger
04-30-2015, 07:25 PM
54F, 46R. 880LF, 870 RF, 730LR, 770RR, 3250 total. I was hoping for lighter....
Yet it handles like a go-cart!

bryant
05-05-2015, 06:31 AM
heres my 71 maverick. it has an 8 point cage, 9" rear, battery in the trunk, no back seat. racing seats, and sound deadener from the firewall to the back of the trunk. also it has my 215 lb butt in the drivers seat
112377

72BBSwinger
05-05-2015, 03:05 PM
That is pretty awesome^^^^, do you have glass front end parts at all? If not, 50/50 should be doable IMO.

bryant
05-05-2015, 07:53 PM
it has a carbon fiber hood, a steel bumper and fenders. oh and that was with just over 1/4 tank of gas. i think an aluminum block would be just the ticket to get to 50/50!

Tomswheels
05-05-2015, 09:30 PM
I wish I could drop 350 lbs off the front and run with you in CAM-S Bry...

bryant
05-05-2015, 09:55 PM
Tom, pull that boat anchor no power engine out, and put a 350lb lighter aluminum 4 cylinder in. You know it will make more power!!!
just kidding, but doesnt the tubular front suspension coil over clips for those car drop near that much weight, then some aluminum heads and you should be close!
Tom, thank you for all you help at the autocrosses.

gator68428
01-27-2016, 09:24 AM
53.6/46.4 F/R weight bias
3488 lbs curb weight no driver
68 Firebird (see signature).
I've lightened the front a lot with aluminum heads and intake, fiberglass hood and TCI Engineering front subframe (with rack-n-pinion steering etc.). Battery in trunk. TCI Torque-arm rear susp may have added some in the rear as well. Lighter front brakes, and Corbeau seats. Car handles pretty well for AutoX and track.

2nd place at Good Guys FL 2015
https://youtu.be/DuLrqhgR2j0

123005
123010

Mtrhd329
02-13-2016, 10:26 PM
https://static1.pt-content.com/images/pt/2016/02/20160116_204119_zpslmhwsazh-1.jpg (http://s134.photobucket.com/user/wells_329/media/20160116_204119_zpslmhwsazh.jpg.html)
1979 c10 5.3l,4l80e,10 bolt, all steel fenders, bumper, hood. With my 260# butt in it. Going to be stripping weight where i can.

https://static1.pt-content.com/images/pt/2016/02/20160131_110758_zpsgewb2tph-1.jpg (http://s134.photobucket.com/user/wells_329/media/Mobile%20Uploads/20160131_110758_zpsgewb2tph.jpg.html)

Yelcamino
02-15-2016, 07:58 AM
This should be an interesting before/after! Here's the weigh sheet on my El Camino before I started the LS swap. Going from a cast iron block / aluminum head BBC to an all aluminum LS3...

https://static1.pt-content.com/images/noimg.gif (http://s263.photobucket.com/user/hlumpp/media/El%20Camino/Yelcamino%20V2/Weigh%20Sheet_El%20Camino_zpsgayegvat.jpg.html)

In addition to the LS3, I removed about 200 lbs or so of stereo components.

Anyone care to speculate on the final numbers?

gator68428
02-15-2016, 12:15 PM
This should be an interesting before/after! Here's the weigh sheet on my El Camino before I started the LS swap. Going from a cast iron block / aluminum head BBC to an all aluminum LS3...

In addition to the LS3, I removed about 200 lbs or so of stereo components.

Anyone care to speculate on the final numbers?

3620 lbs
55% front
45% rear

another69
06-25-2020, 03:51 PM
177190
Late post, but just recently got a set of scales.
69 Camaro
LS3/TKO600
AME front / Speedtech torque arm rear

another69
06-25-2020, 03:57 PM
177192

Lonnies Performance
06-28-2020, 07:41 PM
Since the thread is back from the dead, I'll post a few additional values.
I tried out my new Longacre scales...

68 Camaro RS/SS, 396 w/ iron heads, 4 speed, manual brakes & steering, no spare tire, 1/2 tank fuel.
3374 total, 1996F/1378R, 59/41%

91 Firebird, LS3/T56/S60 AC, PW, T-tops, no spare tire, 1/4 tank fuel
3420 total, 1930F/1490R, 56/44%

02 S10 Xtreme, 4.3 V6/5 speed, regular cab, full options, 1/2 tank fuel
3499 total, 2042F/1457R, 58/42%

nokones
06-29-2020, 04:11 AM
I hope everyone realizes that if you're trying to balance your car to handle on an autocross or roadrace course, you need to weigh with the driver's weight and your car in race trim before you adjust your corners to achieve the 50% crossweight. Otherwise its meaningless without the driver's weight.

holschen
06-29-2020, 01:01 PM
177260
177261
camaro 69
ls3 6l80e
2010camaro rear
with 80kg driver and full tank 112L
and without driver
in kg

EvaaWilli
07-03-2020, 10:22 AM
Replaced some parts with carbon. And this is a completely different car. I plan to put all-wheel drive and the engine from the Audi.

Bugzilla
07-06-2020, 03:57 PM
(These are rough numbers off the top of my head. Its been a while)

Lets see. My Evo is...

3150lb
60% F
40% R

My Bug is...

2100lb
40% F
60% R

Who needs 50/50 distribution!

cpd004
07-07-2020, 03:24 AM
This is before a carbon hood and nose. A few other odds and ends are missing...headliner, rear interior panels, trunk carpet, etc.

https://static1.pt-content.com/images/pt/2020/07/1971Weight-1.jpg (https://postimg.cc/LJ5VNPZd)

71 Firebird Speedtech Xtreme, Ls3, 4L60E, factory 10 bolt, SFC's, Recaro's, mostly factory interior.

Motobrewmaster
07-07-2020, 07:45 AM
I would like to know how my car weighs out. Does anyone have scales I could borough up here in New England? Specifically around the seacoast NH region.

jamminj007
07-19-2020, 04:49 PM
Mine with full interior dynamat, closed cell foam, 4 point DSE cage and custom trunk enclosure. LS2 battery in the trunk

67-LS1
12-25-2020, 04:45 PM
My 66 Chevelle is 3260 lbs with a full tank. F/R is 1760 lbs/1500 lbs so 54/46 bias.
All steel, battery in stock location, full Dynamat.
Without 122 lbs of fuel the weight would be 3138 lbs.

Scott3106
01-07-2021, 04:58 AM
I have a 1985 Monte Carlo SS. Is it worth adding extra weight to the rear of the car to get a better front to rear weight bias or would it be counterproductive? Weight vs performance? I realize that the lower the better but I think you would have to add way to much at or in the frame like we did in nascar cars. I was thinking you may not have to add very much ballast if you added at the bumper.

stab6902
01-07-2021, 05:28 AM
I have a 1985 Monte Carlo SS. Is it worth adding extra weight to the rear of the car to get a better front to rear weight bias or would it be counterproductive? Weight vs performance? I realize that the lower the better but I think you would have to add way to much at or in the frame like we did in nascar cars. I was thinking you may not have to add very much ballast if you added at the bumper.

Unless you're trying to meet the minimum weight of a specific race series, I'd advise against adding ballast. There are other, better ways to balance the car's handling if that's the issue.

Rod
01-07-2021, 08:42 AM
I have a 1985 Monte Carlo SS. Is it worth adding extra weight to the rear of the car to get a better front to rear weight bias or would it be counterproductive? Weight vs performance? I realize that the lower the better but I think you would have to add way to much at or in the frame like we did in nascar cars. I was thinking you may not have to add very much ballast if you added at the bumper.


no is the simple answer... and no to placing the weight at the bumper.... any weight that far back creates a pendulum effect and make handling unpredictable

balance the car with components that help... add a cage and scale, reduce nose weight, fiberglass or carbon nose cap, hood, fenders, inner fenders, use aluminum heads, radiator, block, aluminum or tube core support, move comments that can be moved, Battery, trans cooler, ect