project

i just found out about the 130 club at the bonneville salt flats this weekend and figured id give it a go this spring.

heres a brief description from the official site:

This format provides a rare chance to run street legal vehicles at speed on the Salt, which has enticed many to return with real racing vehicles and compete in the rich traditions of Land Speed Record Racing. To gain entrance into the 130-mph club, the vehicle must run the measured mile twice in the same day at a speed no less than 130 mph. The two runs are then averaged.

the site with all the details can be found here

after looking over 1/4 times and speeds (around 14.5 @ approximately 100 mph) im fairly confident that my rx8 should be able to accomplish this. however i cant find times for anything over 100 mph. im pretty new to this so i might just be looking in the wrong place. could you guys post your thoughts on this? also have any of you driven on the salt? what can you tell me about traction? anything else i should be aware of?

-project

edit: i just realized that times arent important and that i should be looking for speed @ distance. it was initially described to me as being a timed event but that doesnt seem to be the case.

Ike

The pre production model that C&D tested got 0-130 in 33.5 seconds. Someone that remembers math class might be able to figure out what distance you would travel in that time. :p

Dick Carlson

Two things to remember - you're over 4000 feet altitude, and salt is lousy for traction.
Although I did manage 132 in my '93 SHO on I-80 just west of Bonneville, still in the Nevada mountains.

chiketkd

iTrader: (5)

Distance = Speed x Time

If Car and Driver got 130 in 33.5 secs, a distance of just over 1.2 miles was covered.

WHealy

Man this stuff brings back bad college memories ... and not very clear either.

You got to take acceleration into consideration. If you can assume constant acceleration up to the 130 mph speed, you have an averave velocity of 65 mph over the 33.5 seconds. That translates to .6 miles coverd to get to that speed.

However, I'm sure acceleration being constant isn't a fair assumption. All I'll add is that I heard of this challenge before and I don't beleive many stock vehicles have completed it.

Dick Carlson

Notice that it also requires a four-point roll cage in the car. I rather suspect you won't want to do that.

red_rx8_red_int

No, not that easy. Distance = average speed * time. Here we don't know the average speed. It's really a calculas problem, but we can eliminate the integration by assuming a linear acceleration and reduce it to an algebra problem.

red_rx8_red_int

I was too slow to respond, two post in the interim, also what ^^^^^ he said. .6 is closer, but linear acceleration is not a proper assumption.

Ike

Well just using common sense I would say the 1.2 is closer than the .6. If you consider that same car covered a 1/4 mile in 14.5 and it took the car an additional 1.3 seconds to go from 96-100 there is no way I can conceive it would do 130 in only .6 miles since the 130 MPH time was quite a bit more than double the 1/4 mile time. Don't we have some Math geeks hanging around here, I bet I could have figured this out in 7th grade but now I have no clue, so sad....

Ike

Isn't it safe to assume that since the car did 0-100 in 15.8 seconds and 0-130 in 33.5 seconds that the average MPH for the car in the last 17.7 seconds is at least very close to 115 mph?

mattydelbloque

thanks for all the good info. ive also heard that lots of cars that think they can do it cant. im going to try it anyway as i think it will be a blast and even if i cant it should be close. also the rules for the 130 club state the following:

Open cars must have a 4-point roll bar. After market roof modifications are considered "open car". Factory only T-tops must have fiberglass or steel inserts in place when running

whereas the 150 club requires this:

A four- (4) point roll bar approved by a recognized Racing sanctioning organization must be installed in the vehicle; driver is responsible to provide objective evidence of approval. Integral Corvette-type roll bar is not acceptable.

so unless im mis-interpreting the rules i think i should be ok. im curious about the narrower tires recommendation though. to me it seems like with the reduced traction provided by the salt i would want the largest contact area possible. can anyone enlighten me?

ike im right there with you. my capacity for math left the building years ago.

-project

project

last time i checked i wasnt mattydelbloque...

-project

RX8-TX

I am far from a genious, but I believe that the narrower contact area works in the same way narrow tires work for trucks that need to be driven in mudd. In other words, if you had too much contact surface, you would be distributing weight on a much bigger area, thus reducing the pressure applied by the tires on the salt. On the other hand, narrow tires will 'dig' in the salt looking for traction.
Keep in mind you won't be making any hard turns here. What you are looking for is traction on a straight line....forget about braking or turning grip. Just a tire slipping without DSC (or some sort of electronic aid or common sense at least) will send you down to a better life....or you could be lucky enough to tell the tale.

Hope that makes sense...

OverLOAD

Ok,

Here's the scoop on the distance.

You can count on your accelleration being reduced dramatically at each gear change, and reduced further as your velocity (air-resistance) increases.

So, Figuring in like Ike says, that in the 1/4 mile, a car can do 15 seconds, and top out at about 94 mph. That leaves 36 mph to get the the 130, and if the 33 seconds number is right, another 18 seconds to gain those 36 mph. Using the average speed of 2/3 of the max, due to the reduced accelleration at that speed is more accurate.

So, total distance req'd to get to 130 mph =

1/4 mile (1320 ft) (15 seconds)
+
(36 * 2/3 = 24mph average + 94 = 118mph average for 18 sec) = 173.06 fps * 18sec = 3115 ft

For a Total distance of 4435.2 feet (0.84 miles).

This is just an estimate, but I'd bet that this is pretty close to the actual value. If you try it out, make sure you set your trip meter when you start, and keep you eye on it when you're barrelling down the salt flats at 130 mph (j/k)

Have fun,

OverLOAD

Dick Carlson

You know, all this computation is useless, since a racer has a couple of miles to accelerate, there are 3 miles of timed mile scoring, then a couple miles to stop. Not like you have to drag race up to the measured mile. Check out the course map at the Southern California Timing Association web site. www.scta-bni.org

project

yes, it does. thanks!

hmm that doesnt seem to make much sense to me. check out this story at audiworld.com written by someone who has completed the challenge. if you dont feel like clicking, ill paste a bit here...

"To gain entrance to the 130 Club, one must take their vehicle from a standing start to 130 mph within one mile. At the one mile mark there is a 132 foot trap that takes your final speed. If your speed is over 130 then you have to run again over 130 to back it up. If you exceed 140 at any time, you’re disqualified. You have 5 runs to do this."

sounds to me like you do have to 'drag race up to the measured mile'. although after reading this the reality of the challenge is pretty clear. i knew 130 in a mile would be tough but having it all laid out for me in this article makes me think im going to need some after market parts under my belt before i'll really have a chance. im still going to run it stock if for no other reason than contributing my results to the fourm (and it will be fun!).

-project

edit: i had a brain fart. he didnt actually complete it but he participated in the event.

Dick Carlson

I stand corrected - the 130 Challenge is run differently than regular Bonneville Speedweek competition.