I need to add about 245 lbs ballast to my Locost car to compete in SCCA time trials in class U2. I'm thinking of adding a 3/8" steel plate 48"x48" and bolting it up through the frame members at least using grade 8 bolts at 8 points. The idea is to be able to drop the plate and run autocross at a lighter weight. The plate will hang out 3" on each side where I can weld on handles or something. Adequate fastening so it does not fly off and cut a corner worker in half? There is ot much room in this chassis to add weight on the inside low in a central location. Other ideas other than me eating more cheeseburgers?
Eat more? I got nothin' other than that.
I don't know anything about chassis design or flex or whatever, but it seems like adding a second (big!) person to the middle of the car is adding a lot of additional stress to the chassis in a track application?
What about getting some solid steel stock and making a X frame to go under the body with it, maybe bring it up into the body to secure to the triangulation point between the lower space-frame and the upper roll structure tie in? That may distribute the weight better and help reduce chassis flex? I dunno:
How about a 30 gallon plastic water tank filled to the tippity top?
With not knowing the TT classes myself, maybe you can find a class that your car better fits in? Not being a smart ass, that's just a ton of weight you need to add as a % of the overall car.
Lead is 3 times the weight of steel per volume. You're looking at 6 cubic feet of steel vs. 2 cubic feet of lead. I'd look at several smaller pieces of lead placed around the car that will make a bigger overall difference.
245lbs of obscenely large aerodynamic elements?
Woody (Forum Supportum) said:
How about a 30 gallon plastic water tank filled to the tippity top?
a 30 gallon cooling system?
I have not read the rule book, but most rule sets specify that any ballast be inside the car. I would use lead inside. If you are going to drive it alone I would place it to mimic the mass of a passenger fore/aft, but entirely at floor level. 50 LB lead sheets added to the floor, light enough to remove easily. Bolted securely.
Here is another Lotus with a similar solution: https://www.youtube.com/watch?v=-lknIGgWbMY
Is it worth it to run an underprepped car in U2 instead of an underprepped car in U1?
I don't know if you can corner weight the car. If you can, I would try to distribute the weight based on the corner weights to ensure that you end up with a balanced car, and that the added weight doesn't affect weight distribution and thus handling.
In reply to ojannen :
I think 1.4LTurbo has a better chance in U2 at 1,750 lbs minimum weight than running lighter against mega HP U1 cars on big tracks. I like the idea in the video. That was my inspiration.
If you decide to do a plate like the D mod to E mod video shows and you have a similar side exit exhaust, you might consider channels it slides into with a stop on the exhaust side then you won't have to (possibly) mess with bolts near a hot exhaust to install/remove.
