Eifeler

Take a look at the course and see if you think the OP is hitting 140mph down the back straight in a stock C2. Probably feels like 140 with the windows down.

Gary R.

This looks like a good long straight to me!

mrbill_fl

Right, I though BIR was Birmingham, Al, (aka Barber) but that didn't match the OP's home town...

Really, it doesn't matter. I do 130mhp at most tracks in a 180hp car, and that's plenty. his 964 would do that easy and then some where I run.


-the only question I have is whether to do race seats with 3 point belts, and R3... if that's even possible.


edit: what track is that? (name pls)

nevermind... google is my friend 'Brainerd International Raceway

http://en.wikipedia.org/wiki/Brainer...tional_Raceway

Eifeler

Check out the angle on turn 10 and that straight doesn't look any longer than Sebring's back straight.

Gary R.

Maybe they run it counter-clockwise and count the turns backwards......

kurt M

chatting about top speeds is a red herring. 40 mph into something hard can overpower a 3 point. 40 mph offset can overpower many improved systems and will mess you up if you only have a 3 point system.

3 point belts flat out suck in almost every aspect except straight foward clean low energy single impacts. 3 point belts do not hold you back or down or side to side very well and do not give a H&N system anything to hold onto. A 3 point does almost nothing to keep you from slamming the roof in a rollover. You get to hit the roof even if it does not cave in. A 3 point system does little to stop much other than you flying out of the window.

Plan on hitting a tire wall. It happens and happens enough for those in the know to take actions to reduce the medical downsides when it happens. Flipping the car in a DE not so likely. Flipping the car and denting in the roof in a DE is down right rare. Catching fire in a street car in a DE is also very rare. The last two are so rare that they end up on the interwebz and cause much chatter when they happen. Wadding a 9XX into the tires during a DE not so much. Wearing a fire suit in a stock street car, 3 point belted, no cage, no nets, DE car in the summer might reduce safety by increasing the wreck rate from a boiled brain fade. Being in a car fire where you cannot get out is very unlikely. Simply overheating and brain fading happens often. I have seen plenty of students heat fade on me in jeans and a T shirt much less a Sparco oven mitt.

The R3 relies on the shoulder belts not the chest strap to keep the distance between your shoulders and head within range. If you think otherwise find an R3 wearer and ask to pull his helmet off without removing the chest strap. Chest strap digs in a bit the body deforms a little and the helmet comes right up and off. In a wreck the head would not come out of the helmet the head gets pulled away from the rest of the body. H&N systems do not keep your head from moving foward and pointing your face down they keep the distance between the head and shoulders inside a survival range. With a 3 point system there is nothing to keep the R3 back plate from sliding right up your back as your upper torso deforms into a "C" shape and the top of your head points to the impact point. You will bend into a "C" when you hit something hard. Your head will point to the hit and your shoulders will follow. Watch the H&N videos and you will see that this is common with all the systems.

DE. Plan for what is likely to happen rather than what you fear. Racing? Full boat system or go buy a bicycle and race that.

HalV

I don't know about Sebring but this a mile long straight. It is also used for NHRA drag racing so it has to be long. My speedo says 140 mph as I approach turn 1. The speedo could be slightly off at that speed, but I can hit the rev limiter in 4th (130 mph) with plenty of straight left for 5th, so I don't think it is off by much.

Turn 10 is banked so you get a good start before you even hit the main straight. Turn 1 is banked so you don't need to slow down much (in fact the fast gujys don't slow at all). I only feel comfortable taking turn 1 at about 120 mph. I've been told that GT3s can hit 170 mph down this straight. I was with an instructor in his GT3 and we were doing 155+ in turn one in light rain.

This is a Nortdstern DE where rules are Window's Up.

HalV

I just read that Sebring is about 1200 yards, so less than 3/4 the distance of BIR's main straight. Here is a quote from the BIR track page

HalV

We run it clockwise.

HalV

Right, I'm not claiming this takes any skill, other than pushing the gas pedal. I just made the speed reference so that folks could help me prioritize safety equipment.

white924s

I'm in a similar position - I am getting pretty close to running solo (have been signed off with a couple clubs in the area and my goal is to get into solo groups all the time by the end of 2013 season) but have not yet invested much in safety gear (to date, I've focused my investment in getting as much seat time and instruction as possible). Beyond the basic helmet/fire extinguisher, I did get a pair of gloves and Sparco driving shoes last year, and I found that they improved my feel on the controls (steering wheel, pedals), which I think helped me be more precise.

I want to get fixed race seats, harnesses and a HANS, but my main reservation has been the roll bar question. I have heard a lot about how race safety systems lock you in place, which could be a problem in a rollover. However, in such a situation, to avoid injury, I would need to basically do a sit-up inverted and accelerating downward at at least 1g to prevent my head from impacting the roof (I'm mainly concerned about the damage from the initial impact in a rollover). It seems to me that I'm at risk now even with stock safety gear, so race harnesses and a harness bar would leave me no worse off than I am now.

Would a properly mounted roll-in cage and fully stripped interior be safer? Almost certainly, but that would mean that I couldn't drive my car to the track, nevermind the problem of trying to park a tow rig in NYC. A bolt-in roll bar might be a good compromise. However, the bolt-in bars that require welded-in backing plates on the sills (e.g. Safety Devices) cost almost as much as a full cage, and the bolt-in bars for 944's that mount to seat belt attachment points (Heigo, Redline) seem to offer only limited rollover protection. They are less expensive than welded in units (especially considering installation costs), but I go back and forth on whether the extra protection justifies the price premium over a Brey-Krause harness bar.

This post is getting long-winded, but I appreciate hearing everyone's thoughts and experience on this issue

Eifeler

With a banked T10 (even though it looks to be 110+ degree's) and 1mile straight I'll humbly stand corrected.

Back on topic....at those speeds you're wise to gear up sooner rather than later. With the loads that are placed on tires in banked turns it would be a good idea to keep a close eye on your tire pressure and condition. A blow out in the bank at 120mph would be bad news in any car.

HalV

Thanks for the advice, Eifeler, your input is very much appreciated.

dgmark

I wrecked my car at Road America in the Kink in my first year of DE. The speed at impact was 60MPH. The first thing I did before putting it on the track was install proper seats roll bar and 6 point harnesses. Except for some soreness in my shoulders I was ok. Personally I wold not track any car without proper restraint it's just the price of admission.

Upstate101

You could start with a welded half-cage. That would allow you to safely mount harnesses and proper racing seats while still keeping it capable of every day street duty. You can even keep the interior otherwise looking stock if you wish.
Then, when you become hopelessly addicted, you can convert the half-cage to a full cage, gut the interior, and trailer it to the track.