Ballast

#1

What do you use for ballast and how do you actually attach it to the passenger’s side seat mounting points? Pics are worth a million words.:slight_smile:

#2

I don’t need any in this car, but in my 944 I used 1/2" Steel plate. That’s the max thickness that my steel shop can "punch" a hole in. I just made a template from cardboard and had them stamp out plates which I could stack. Each one weighed about 48lbs. I calculated the weight first with some formulas that I fould on the Internet and they were pretty close.

You could duplicate this same setup for the BMW with one plate. The front seat studs should be tall enough.

#3

Not sure about mounting it to the stock seat locations but you can go to your favorite sporting goods store and buy some weights for ballast. Just drill a hole in the floor.

#4

I used five 10 pound steel dumbell plates, the ones with a 1" diameter hole in them. Fastened them to the passenger floor board where the seat used to be using grade 8, 1/2" x 6" bolt and heavy duty fender washers. Very secure and only took about 10 minutes.

#5

Cool!
I like all the ideas, specially the dumbells.
Thank you guys.

#6

just remember the spec e30 requirement for number of bolts holding the ballast down.

[quote]9.3.13.2.3. Each segment shall be fastened with a minimum of two (2) one-half (1/2) inch bolts and positive lock nuts of SAE grade 5 or better unless the ballast is mounted using the four (4) passenger seat mounting points and replacement bolts, and shall utilize large diameter, load distributing washers.
[/quote]

cheers,
bruce

#7

leggwork wrote:

[quote]just remember the spec e30 requirement for number of bolts holding the ballast down.

[quote]9.3.13.2.3. Each segment shall be fastened with a minimum of two (2) one-half (1/2) inch bolts and positive lock nuts of SAE grade 5 or better unless the ballast is mounted using the four (4) passenger seat mounting points and replacement bolts, and shall utilize large diameter, load distributing washers.
[/quote]

cheers,
bruce[/quote]
Yes, that’s why I asked for pics.

#8

BETO wrote:

[quote]leggwork wrote:

[quote]just remember the spec e30 requirement for number of bolts holding the ballast down.

[quote]9.3.13.2.3. Each segment shall be fastened with a minimum of two (2) one-half (1/2) inch bolts and positive lock nuts of SAE grade 5 or better unless the ballast is mounted using the four (4) passenger seat mounting points and replacement bolts, and shall utilize large diameter, load distributing washers.
[/quote]

cheers,
bruce[/quote]
Yes, that’s why I asked for pics.[/quote]

Interesting, I never noticed that or was ever tech’d for that and it’s now my 5th season with NASA. In addition to the plate setup in the 944, I also had 25lb dumbell plates stacked with 1/2" grade 8, but you can only put one down the center. I had to carry over 250lbs in '44cup and there was ballast everywhere.

#9

it is a Spec E30 specific rule. For dumbells I’ve heard of putting a bolt in the center and one at the periphery and bolting down a clamping bar/plate between them.
cheers,
bruce

#10

I don’t have pics of our solution yet because I haven’t installed it but I salvaged the rear hunk-o-steel from an iC which weighs approx 50lbs (will weigh it this weekend). It conveniently has 4 nice holes in it for securing it. I plan to use the largest fine thread bolts that will fit which are larger than those required with giant fender washers.

Note that this is an interesting peice of factory ballast as it is actually an engineered damper. Considering the softness of the rubber isolators I’m sure it’s for some type of pitch/roll mode (possibly bounce). I checked factory pricing on it…$575. ; ) Course I’m sure even on ebay this is worth nearly zero.

Anyway, it’s a neato factory solution which we already had here anyway. I’ll get a pic when it’s done.

The dumbell solution seems to be popular in other series too but the mounting scheme people typically use (through the center with a single bolt) is not compliant in any series that I’m aware of.