car weight

#1

what sort of weights are you guys at minus driver? i’m in the process of my build and wondering how much weight to take out and still be able to meet minimum weight without requiring ballast. anyone willing to share data? the current min weight seems rather high for an e30? i know of many e36s getting below that weight. what am i missing?

#2

I’d say to take out everything you can from the cabin and front of the car. I also take the trunk tar out and run a spare as part of the ballast. on the 96 (RIP) I needed 35lb of ballast to make weight, but I did have a passenger seat installed.

#3

Don’t be in a rush to remove the trunk tar. Get your car to it’s completed config. I mean really completed. Passenger seat, crankscraper, oil pan shield, sunroof, window glass…get your car to the point to where you can really say “I’m done”. Then after all of that if you are over weight, remove tar.

It’s common for folks to remove the tar and then end up lighter then they’d planned.

#4

well it’s a 91, there is no trunk tar. but yes i will be weighing it after most of the stuff is in. at this point i’m just worried about taking the interior sound deadening out in fear of not making the min weight, it seems high to me.

#5

Did the 318s not have trunk tar?

On our 91 325is we have all the trunk tar except where the sway bar reinforcement comes through the floor, run a spare, start full of fuel before a race and have about 25 lbs on the floor with a 180lbs driver. Weight on the floor will vary by about 10 lbs depending on the track scales, so if you want to always be as light as possible be sure and make it easy to change at the track. I built a weight platform to bolt in where the passenger seat goes and have drilled weights that attach to that.

#6

jeremy, no it didn’t but neither does my '91 325i. That’s odd that yours does. i’m going to keep the interior sound deadening at this point and will re-check once everything is in as to if it needs to come out. I guess my point is that i’m wondering why the min weight was set so high when these cars can obviously be quite a bit lighter without too much effort. 2600 would be a good min weight imo.

#7

If you over build the cage then you’ll make weight :wink:

Seriously tho’ I left all the glass in, doors too, all electric motors, etc I also have a matching passenger seat so my daughter can do HPDE in the same car - without the trunk tar and a full tank before the race I’d come in ~2780 after a 30 min race - and I weigh ~230lbs.

After a recent repair we left the door glass out and electric motors and I now have ~75 lbs of ballast under the passenger seat. B)

Hope this helps…

#8

I have an 89. Two race seats, cool suite system, all glass and motors, no trunk tar, no spare, rest of interior is gone within the rules and I use about 50 lbs of ballast. I weigh about 160 w/ gear. Also need to start with a full tank of gas and come in around 2770 after a 30 minute race.

#9

I suspect that the min weight was taken from the SCCA IT spec for this car. It was known to be easily achievable.
There’s nothing wrong with using ballast if you fasten it down well.
bruce

kishg wrote:

#10

leggwork wrote:

I am still puzzled why we don’t drop 50-75 lbs. from the minimum. I don’t know anyone who couldn’t drop that much weight easily. I have a stout cage and still have to run a full cool suit box, trunk tar and spare.

Less weight would mean longer lasting tires and brakes, better fuel economy, better handling. But for some reason, the idea never seems to gain any traction with the powers that be.

#11

there was a big thread over a year ago … here it is
http://spece30.com/component/option,com_kunena/Itemid,94/func,view/id,25002/catid,3/limit,10/limitstart,50/

where it seems that as many were saying stay-the-rules-stability-course as those who were advocating for a lower weight.
bruce

#12

agree with steve… i think 100lbs can come off fairly easily. i don’t hold a nasa license (yet), so I think some of you old hands might want to propose it?

#13

It pains me to agree with Steve D. but 50-100 pounds wouldn’t hurt when it comes to tires and brakes.

To Bruce’s point I think this was a direct lift from the IT rules. I also think the resistance was mainly:

a)JP thinking he was going to continue to gain weight and needed the buffer
b)the 318 variable which isn’t a factor

I personally can vary the car weight by probably 200+ pounds with fuel, ballast, and accoutrements (i.e. cool shirt, etc)

I can also vary the driver weight by 30 lbs. but that is more difficult and not as fun.

#14

Now that the 318 is gone, it seems like one of the top reasons for NOT lowering the minimum weight is “…I haven’t solved my car’s fuel starvation problems without running a full tank.”

Now THERE is a lame reason for costing everyone else money in consumables. :stuck_out_tongue:

I don’t see this as a rules stability problem. The rules have allowed removal of certain things for a while. Most people don’t remove that stuff simply to stay up to the minimum. I am a huge proponent of rules stability when updating your car costs money (spec exhaust, adj fuel pressure regulators come to mind), but lowering the minimum weight is easily accomplished by 90% of the field.

I’m still not convinced that having a lot of weight in the trunk helps balance the car out by getting weight off the front. It simply creates a barbell with a high polar moment. Besides, shifting weight forward and back is the only way to “adjust” the fixed front bar. :wink: Of course, since I like to run with the rear bar all the way soft, if I take weight off it will become a stiffer spring, which will make the car looser. Time for a test day…

#15

The old arguements for reducing the spec weight were usually “so we will be faster”, which wasn’t that great of an arguement. But this “saves tires and brakes” arguement seems pretty reasonable.

#16

I’m down with lowering the weight 100lbs. I see almost every drive adding weight to meet race-weight. One could argue that there are some needless safety concerns when driving around with a stack of weights in your car. Sure… they are secured down but it’s not something I’d want to see come free in an incident.

Just my 2 cents
Scott “stokin the fire” Mc

#17

Agree with scott and steve. why carry additional weight you don’t need which would increase consumable cost and be a potential safety concern?

#18

If someone wants to formally submit this as a rule change, they better hurry. Don’t look at me, I don’t care enough about the issue.

#19

From what I remember of the times this has been mentioned in the past, there are some cars that seem to be heavier than others. I don’t think it was looked at too closely, but for whatever reason, there were cars that would have difficulty loosing an additional 100lbs. That said, I have all the glass/power windows, spare tire, 35lbs of ballast and go out with a full tank.

#20

Knowing what I do about automotive crashes (day job), I don’t mind at all a weight that includes the need to run a spare tire. I say take 50lbs off for 2010 and see how that actually works out for everyone.