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If one were to try for a top speed run in a GTS, what should be done to the vehicle?
I have heard stories of the windows pulling of their seals above 180. Should the windows be opened a crack?
Also, what kind of air pressure in the tires?
Any other suggestions?
Thanks in advance!
 

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recommended pressures on the tires you plan to run. If you are going to continually make multiple passes, make sure to monitor your pressure's as they will increase. Pressures in the tires are affected the greatest by acceleration and deceleration.

We have run both MXX3's and Pilots at those speeds. Whatever tire you plan on using, make sure it's Z rated or the highest rating you can aquire in your tire. Don't run that fast with a tire that's underrated for the speeds you want to attain.

Your selection of road to run on should be as smooth and flat as possible. Be careful where you choose to make your runs and check the road at lower speeds. Make sure there's no "dips" or "swales" in the road that you might encounter towrds the end of your run at top speed. The undulation might be very slight and hardly noticeable at 120mph, but at 200mph you don't want to encounter any serious types of "dips" that could lift your front end or get air underneath.

I would leave the windows completely rolled up.

Inspect everything on your car, especially underneath your car before you plan to test at high speeds. It's always good to put a wrench on everything underneath and check bolt tightness. You could have 1 loose bolt on your u-joint and the rotation at those speeds could create a serious problem. I would recommend getting driveshaft loops and halfshaft loops.

Safety is always #1. Take safety seriously, even if you just plan to go and do something like this once. It only takes once for something to happen. :thumb:

Gearing is another important factor that can be calculated by many different software programs.

Rjr.
 

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ViperBing,

In addition to what has already been mentioned, I would also recommend you make sure you have the car aligned with you in the driver's seat with the pressure you intend to run. I would recommend you running the maximum pressure listed on the sidewall of the tire. I have run a higher pressure than what I normally run(which was 32 PSI front 30 PSI rear) that was on the car when I had it aligned and the car felt different{not as good} at the same speeds than with the alignment PSI.

I definitely recommend a smooth, 3-4 lane wide open surface preferably with no entrance ramps. A surface that has truck ruts can be difficult under certain conditions at regular highway speeds. Do not even consider such a surface.

Also, keep in mind a Z-rated tire is an antequated measuring stick of a tire's top speed capabilities:
==> The Z-rating(150+ MPH) came about when they thought cars would never go much faster than 150 MPH. Obviously they were wrong. Since then, there are now W and Y-rated tires. A W-rating is good for 168 MPH and a Y-rating is good for 186 MPH. All MXX3 and Pilot Sport and Pilot Sport Cup tires for the stock Viper tire sizes are Y-rated.

I would also recommend taping the hood shut and removing the foam seals that seal the wheel wells to the hood. I lose those damn things all the time!

Get a 6-point harness installed.

Make sure you wear a helmet and nomex racing suit.

Have a fire extinguisher on hand.

Make sure your tires are fresh ie a relatively recent manufacture date.

Have all suspension bushings checked.

Grease all ball joints.

How much RWHP do you have? How long are you planning to stay in it? ==> I noticed you have a supercharger, I would make sure you have a dual wide band O2 and EGT sensors on the #'s 9 and 10 cylinders which usually run the leanest.

Do you have an upgraded fuel system to accomodate the extra powe rassociated with the roe Blower/8# pulley?

I would also ask Nadine(from the UK) I know she is going to do or has already recently done some standing miles with the Roe Blower.

Oh yeah, GOOD LUCK!
 

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Excellent advice from SVS and PC. Drag radials aren't recommended at high speeds. Whatever you do, just do it safely (which it seems you will).

I would also ask Nadine(from the UK) I know she is going to do or has already recently done some standing miles with the Roe Blower.
Best bet is to post about your top speed test here - http://www.pistonheads.com/gassing/forum.asp?f=76&h=0 . Nadine Geary posts on there more often then on here.
 

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On top of all the excellent suggestions posted so far, do your runs at an organized event such as Sandhills, SilverState etc. It's a lot more fun when your'e not worried about other cars, animals or whatever. I ran the SORC mile @ 189.2 mph in my ROE SC GTS, 7 lb pully. I was still pulling strong at the finsh line. You might want to check your fuel pressure with the 8 lb pully. Your'e near the edge.
 

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All good suggestions above. I will throw in the following:

1. Set cold tire pressures at the maximum rating by the manufacturer. The less tire pressure you have the more distortion it has and the more heat it puts in the tire. This effect is called 'sonic wave'. Tire failures are the most common serious problems among open road racers.

2. If youre doing a top speed deal as part of an open road racing event, great. Just ask around to the veterans on what to do and they will help you. If you are doing a bonzai run on some test road, be careful and if you crash, dont take anybody else out in the process.

3. Inspect every inch of each tire for screws, nails, cuts, gouges, etc. before you run.

4. If you encounter an animal, dont swerve, just point straight and hope that it is able to move out of the way. Lots of people lose control and die every year trying to avoid critters. When in doubt, go straight. And if you take out a critter in the process, then its better them then you.

5. I personally like to crack the windows a 1/4 inch. This helps equalize the pressure at speed. And even when you know they are going to pop out and make a bunch of noise, it still scares the crap out of you when they do. So I just avoid that all together and crack them open a bit.

6. On Gen 1 and 2 cars, i remove the weather stripping on top of the front fender wells. At speed it can blow out and flop around and if this happens to you you will freak out and think that a tire is coming apart.

7. For extended high speed runs you really need a diff cooler.

8. Work your way up to speed gradually. Maybe speed up in increments of 10 mph and get used to it at a gradual pace.

9. For open road races beware of getting tunnel vision. its easy to get used to the speed and just focus down the road. you almost need a pilots process of scanning the road from side to side and then doing an occasional scan of your critical gauges to make sure the car is running as it should.

10. Always be smooth in your steering inputs and at high speed the inputs are very slight. If you have to stop or shut a run down early, gently lift while in a straight line and let the car settle for a few seconds before gently squeezing the brakes and bringing speed down at a controllable rate. Any sudden steering moves or sudden braking, especially while in turns, will kill you faster than you can read this sentance.
 

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gtsbob said:
On top of all the excellent suggestions posted so far, do your runs at an organized event such as Sandhills, SilverState etc. It's a lot more fun when your'e not worried about other cars, animals or whatever. I ran the SORC mile @ 189.2 mph in my ROE SC GTS, 7 lb pully. I was still pulling strong at the finsh line. You might want to check your fuel pressure with the 8 lb pully. Your'e near the edge.
That's awesome gtsbob! Congrats! :thumb:

How was the event this year? I know West Coast Viper won the standing mile. Ron Adee won the half mile (In a race prepped Dodge truck!) and the unlimited Open Road Race. What other highlights? We really wanted to go but opted to do the V10 Nationals. Great people in that little town of Arnold with the coolest road race in the country, IMHO. Now that Ron beat my time in the ORR, I definitely have to get back there next year and tackle a higher avg. mph.

I thought a Busch Cup Car was going to race in the ORR?

r
 

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R jr
I was looking forward to seeing the SVS and Paolo's Viper run this year. I think the Vette guys were relieved you weren't there. Had I known I would be as competitive as I was, I would have tuned for 100 octane instead of 96. I only ran the shootout because I was late signing up. Ron was the only entrant in the unlimited class. I think there were two wrecks, a C2 vette and a Ford Contour. Nobody was injured. There was a Winston Cup car entered in the 120 class but he DNF. He ran 188.5 in the mile, just barely slower than me. We need to get more Vipers entered. There was 38 Vettes and only 7 Vipers.

Bob David
 

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gtsbob said:
R jr
I was looking forward to seeing the SVS and Paolo's Viper run this year. I think the Vette guys were relieved you weren't there. Had I known I would be as competitive as I was, I would have tuned for 100 octane instead of 96. I only ran the shootout because I was late signing up. Ron was the only entrant in the unlimited class. I think there were two wrecks, a C2 vette and a Ford Contour. Nobody was injured. There was a Winston Cup car entered in the 120 class but he DNF. He ran 188.5 in the mile, just barely slower than me. We need to get more Vipers entered. There was 38 Vettes and only 7 Vipers.

Bob David
Bob, congratulations on your very fast MPH!

I would have loved to run the standing mile, but I am not done with my car yet. It is taking longer than I anticipated but is comiong along just fine.

Good luck and take care, Paolo :thumb: :thumb: :thumb:
 
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