Show Me Your Weight!!

[Devil Dog Mosport]

Need to add nearly 200lbs to my 84 Porsche 911 for the correct NASA Race Class. Car is stripped , so passenger side floor is open.. at 2775 need to be 2917Lbs min..

What is anyone using for Ballast Weight and anyone using as much as 200 lbs ??

[winders]

Originally Posted by Devil Dog Mosport

Need to add nearly 200lbs to my 84 Porsche 911 for the correct NASA Race Class. Car is stripped , so passenger side floor is open.. at 2775 need to be 2917Lbs min..

What is anyone using for Ballast Weight and anyone using as much as 200 lbs ??

How about 300 lbs?



Scott

[Walt Fricke]

When I needed some pretty hefty weight I had a local welding shop cut some standard width half inch steel plate to lengths I specified (I ran it crosswise across the floor pan). He also drilled half inch holes which lined up with each other so I could stack it. Worked just fine as long as I needed it, and they now provide a hard surface on parts of my work bench.

Be sure to use something stout (something better than standard body washers) as backing for your fasteners on the underside of the floor pan. Best, in fact, to weld them onto that side of the floor pan, which will greatly reduce the ability of a 10G flop on your car's top to pull the weights through the sheet metal of the floor pan.

[Devil Dog Mosport]

Originally Posted by winders

How about 300 lbs?



Scott

Wow.. What are the bars material? and the battery box too?

thanks

[Devil Dog Mosport]

Originally Posted by Walt Fricke

When I needed some pretty hefty weight I had a local welding shop cut some standard width half inch steel plate to lengths I specified (I ran it crosswise across the floor pan). He also drilled half inch holes which lined up with each other so I could stack it. Worked just fine as long as I needed it, and they now provide a hard surface on parts of my work bench.

Be sure to use something stout (something better than standard body washers) as backing for your fasteners on the underside of the floor pan. Best, in fact, to weld them onto that side of the floor pan, which will greatly reduce the ability of a 10G flop on your car's top to pull the weights through the sheet metal of the floor pan.

Okay, also something about one (1) 5.5 bolt per 10lbs of weight per NASA CCR? They may vary by tech and region...

thanks

[RichardNew]

You better get your scales out before you start adding weight. You want the weight as low as possible and have it contribute to your corner balance.

All race cars are built as light as possible. Weight is added to make it legal.

In NASCAR they actually take all the gauges out for qualifying and add the weight to the floor. They want the weight as low as possible. You just don't need gauges for a 2-lap qualifying run. Better to have the 1.5 lb bolted to the floor.

Richard Newton
Car Tech Stuff

[Devil Dog Mosport]

Yup, get it makes sense.

Most likely spread evenly on passenger side floor, and checked with scales.. I weigh 245lbs, so could also be nice counter balance....??

[Cory M]

no pics, but we use lead bricks bolted to passenger floor

[Walt Fricke]

With lead you have to be very careful about fastening. At a Club Race at Road America 10 or so years ago, after a nasty wreck the track crew found lead weights lying on the track. The bolt heads had simply pulled through the lead because it is so malleable. Of course, the engine ended up out on the track also. As I said, nasty. Luckily, none of that flying lead hit the driver.

Were I to use lead in bricks or pigs or whatnot, I'd want to lay a layer of 1/8" or so thick steel over the top, and have my fasteners go through that and the lead. That ought to deal with pull through. No doubt a suitably wide and stiff washer would do also, but why not overkill.

I also wonder how valuable it is for the likes of us to use lead? Because of its density, I suppose you can get the CG down a tiny fraction of an inch lower than using steel. But are any of us really at the NASCAR remove the gauges (thanks for that tid-bit) level? Lead is traditional, but is it that practical? If you are constantly adjusting the weight, a steel box with lead shot in it makes some sense. Add or remove a scoop and screw the cover back on?

Depleted uranium, anyone? You want heavy, that's heavy.

[winders]

Originally Posted by Devil Dog Mosport

Wow.. What are the bars material? and the battery box too?

thanks

2.5" x 2.5" steel square tubes filled with lead.

Since the car needed the weight, a regular sized battery was used.

The side to side weight of the car with driver is 49.8%/50.2%.

Scott

[IMR-Merlin]

We used lead in the NASCAR cars I worked on. Lead is cheap if you know someone that works at a tire shop. You can make some tubes like in Scotts car, but cut one of the long wide lenghts off, almost like steel baking pans. You can smelt your lead in them, and always use a heavy fender washer to mount lead. As noted before in this post, bolts will pull through.

[Walt Fricke]

Devil Dog - that battery box looks like an ordinary marine plastic battery box. I bought a fancy Moroso one for my car, with Dzus fasteners holding the top on, and a vent line out the floor pan.

However, when it comes to trying to keep battery acid away from things, all these boxes tend to have a problem. In a boat, it may be fine to toss the battery in the box, and strap the box down to the deck or wherever. Not so in a car, especially a race car. So you end up punching two holes through the bottom of the box for the rods which, with a cross piece up top or the like, hold the battery firmly in place. Now the acid tight integrity of the box is compromised somewhat.

But if your battery is sealed, that part doesn't matter, and a nice plastic cover surrounding the battery keeps stray metal objects from trying to weld things or cause sparks.

[Devil Dog Mosport]

thank you Gents!