PDA

View Full Version : First trip to the dragstrip



ArrestMeRed04
11-18-2013, 07:29 PM
Well it was a little warm and humid to get a new personal best in my Ram so I decided to run the car for fun. Really disappointing results, really had to take off like a little old lady or else it'd just kill the tires.
First run was against a CTS-V who also had on paper plates, tried 2000rpm off the line and is was laughable. 2.49 60'
http://m.youtube.com/watch?v=tR6XMK31zr8
Second pass I went off idle and bogged a bit, then it lit the tires up when I hit 2nd.
http://m.youtube.com/watch?v=yVUmXJDaFdU
Third pass I tried just above idle and slipped the clutch, then hit 2nd a little easier.
http://m.youtube.com/watch?v=uBJtFkV-Ahw
Really thought a 345 series tire would hook better but it was still fun to tear up something other than my truck. Planning to get a set of drag slicks for it soon, how does the driveline hold up on these at a dragstrip?
There was also a red 98 GTS that showed up and made a couple passes, April and ?I didn't catch her husbands name, but nice folks and told me about a large car club down in Austin I'm going to look into. Finally, here is a vid of what the truck runs, hopping to get it a little quicker and then put the nitrous on the car and eventually try for 9's.
http://m.youtube.com/watch?v=qsN9ICiKs2c

Disturbed
11-19-2013, 11:54 AM
Def need to work on that launch and shifting speed. What was your tire pressure? Are you still running run-flats? If you are stock and do alot of street miles the nitto invino's are a good choice along with Pilot SS's. 2500 rpm with some clutch slip works for me and I'm not the best drag racer but 1.6-1.7 60ft are pretty normal.

ArrestMeRed04
11-19-2013, 06:26 PM
30psi first pass 25 for the next 2, running pilot sports from 2002 up front and 2007 on the rear, was looking at the nitro drag radials for the stock rims. After some more seat time I'll start power shifting it. The reason I'm planning on full slicks is I'd like to be in the 1.4-1.45 60' or quicker. I live 2 miles from the dragstrip so I end up there a lot. 1.6-1.7 on 19's would be fun too. What have you run and with what mods?

Nine Ball
11-20-2013, 05:04 AM
Your car isn't making enough power, or geared properly, to cut 1.4 60' times. You'll want to upgrade the clutch, the rear half-shafts, and probably do a Wavetrac differential and 3.55 gears if you want to dump the clutch on slicks. With drag radials, you should easily be able to achieve 1.6-1.7 60' times, without any other changes to the drivetrain.

If you are still on run-flat tires, get rid of them ASAP. Those are the cause for more Vipers losing control, than anything else. Pure garbage traction-wise.

ArrestMeRed04
11-20-2013, 06:33 AM
Spraying a 200 shot do you still think it'd need the lower gearing? And if I'm understanding you correctly the halfshafts should hold up to the 1.6-1.7 60's ok? I'll start looking at tires soon, leaning towards the nitto drag radials for the rear haven't looked on the fronts yet

Disturbed
11-20-2013, 06:36 AM
Tire pressure was a bit high. Depending on track temp I will go 15-17psi. Try dropping pressure another 1-2psi. It never stops surprising me how such a small chance can affect the car. I haven't drag races the SS's but start at 20psi.

Practice, try daily driving the car for a month. It's a car, it will not melt if it gets wet. Lol. I like launching hard on the street in 45mph zones...best place to Learn. It also is a good place to learn reaction time by watching the lights. :-)

If you want to launch hard on DR or slicks you NEED to upgrade your half-shafts or you will be taking the flatbed home. I have never broken a stock half-shaft ever but my launch is smooth. Dumping the clutch only breaks stock parts IMHOP.

This is me @ OSW...a track known for poor prep.

http://m.youtube.com/watch?v=7j1xZ_JmMck

ArrestMeRed04
11-20-2013, 06:06 PM
Nice, that's about where I'd like to be without nitrous. Do the gen2 half shafts fit the gen3 cars? Wasn't sure how low I could go with the air pressure before they started cupping. I do want to get a new set of tires before I daily it and get stuck in the rain, will have some more fun wasting the rears that are on it though.

ICPREY
11-20-2013, 06:14 PM
Do the gen2 half shafts fit the gen3 cars?

Gen 2 shafts will break on slicks with a hard launch, some have even broke them on street tires. I would suggest upgrading to Unitrax shafts.

ArrestMeRed04
11-20-2013, 06:59 PM
Gen 2 shafts will break on slicks with a hard launch, some have even broke them on street tires. I would suggest upgrading to Unitrax shafts.

I was looking at the 1200hp shafts from the driveshaft shop, what do the unitrax run $$?

99RT10
11-20-2013, 07:03 PM
Typically the *00 HP shafts are $800-$900 for 2.

ArrestMeRed04
11-20-2013, 07:07 PM
Typically the *00 HP shafts are $800-$900 for 2.

That's not too bad at all.

Disturbed
11-20-2013, 08:50 PM
I have a set of gen2 1000hp GeForce shafts that are new id sell for $1000 + shipping. Gen2 shafts WILL NOT fit gen3 totally different.

Venomous1 Racing
11-21-2013, 11:22 AM
Hey Justin, good to see ya here bro. Figured I'd visit and see the ways of the Viper Cars. Nine Ball is a cool cat from my LS days and sure he has some useful info.
As far as tires go, I'd like to see you on slicks instead of DRs. If it were a street terror I'd say DRs, but Witt you being a 1/4 racer slicks will do you better IMO. I'm sure others will chime in as I don't own a Viper Car but very familiar with racing on both sets of tires. I recommend DRs for Auto cars or Mexico racers, slicks for stick cars and track cars. As you personally know, a taller sidewall helps absorb much of the shock imposed by the drivetrain hit also aiding in traction. The thin , non wrinkling wall of a DR doesn't allow any shock absorption and can initiate wheelhop which is the major cause of failure to half shafts, axles, differentials, and even wheel studs. I'd love to hear more opinions on the subject although im sure its been discussed many times. Lol

Nine Ball
11-21-2013, 11:59 AM
Spraying a 200 shot do you still think it'd need the lower gearing? And if I'm understanding you correctly the halfshafts should hold up to the 1.6-1.7 60's ok? I'll start looking at tires soon, leaning towards the nitto drag radials for the rear haven't looked on the fronts yet

Ideally, you want to finish the 1/4-mile near the top of 4th. Shoot for finishing at around 6,000 rpm in the Gen 3, if you are still using the factory rev limiter. This will result in the highest mph and best ET.

Working backwards, estimate what trap speed you want to run. Then use this site for figuring out which combo of tire height and final drive gearing ratio gets you to that trap speed at 6000 rpm.

Enter tire height (stock is 27.0, most DR's are 28.0)
Enter 6000 rpm
Enter "1" for 4th gear. Other gears don't matter.
Enter final drive ratio (stock is 3.07, but 3.33 and 3.55 are common aftermarket ratios)

http://www.apexgarage.com/tech/gear_ratios.shtml

Example Results:

26" tire and 3.55 gear = 131 mph in 4th
27" tire and 3.33 gear = 145 mph in 4th
28" tire and 3.07 gear = 163 mph in 4th

I'd be aiming at the 140-145 mph range if you plan on running 9s.

ArrestMeRed04
11-21-2013, 12:49 PM
I was looking at that last night and was leaning towards the 3.33/27" tire

However a 3.55/28" tire could still get me to 145 with a 6200 rpm limit, and still be a lower overall ratio than the 3.33/27

Nine Ball
11-21-2013, 01:10 PM
Don't forget that trap speeds will be slightly less than the gear/mph calculator shows. Those calculated mph are the max mph, which would be seen at the end of the speed trap. The trap speed is calculated from an average of the entry speed and exit speed of the trap.

Example, I run the Mickey Thompson 345/35-18 drag radial (27.5) and 3.33 gears. I'm on the rev limiter at 6400, when my trap speed is 153-154. The mph/gear calculator says 157. So, subtract maybe 3-5 mph from what the calculator states, to target your trap speed.

Another thing to think about, the taller gear ratio will be a stronger gear set. The pinion gear on a 3.07 is beefier than the pinion gear on a 3.55 gear. I'd opt for the taller gear ratio and shorter tire combo, when possible.

ArrestMeRed04
11-21-2013, 02:48 PM
Good point on the pinion gear, and with the 3.33 it leaves the option to go up to a 28 or even down to a 26 if needed. Have you ever kicked around the idea of running a full slick on your car?

ArrestMeRed04
11-21-2013, 02:50 PM
Hey Justin, good to see ya here bro. Figured I'd visit and see the ways of the Viper Cars. Nine Ball is a cool cat from my LS days and sure he has some useful info.
As far as tires go, I'd like to see you on slicks instead of DRs. If it were a street terror I'd say DRs, but Witt you being a 1/4 racer slicks will do you better IMO. I'm sure others will chime in as I don't own a Viper Car but very familiar with racing on both sets of tires. I recommend DRs for Auto cars or Mexico racers, slicks for stick cars and track cars. As you personally know, a taller sidewall helps absorb much of the shock imposed by the drivetrain hit also aiding in traction. The thin , non wrinkling wall of a DR doesn't allow any shock absorption and can initiate wheelhop which is the major cause of failure to half shafts, axles, differentials, and even wheel studs. I'd love to hear more opinions on the subject although im sure its been discussed many times. Lol
I'm going to get the drag radials for the street and slicks for the track...

Nine Ball
11-21-2013, 04:13 PM
Good point on the pinion gear, and with the 3.33 it leaves the option to go up to a 28 or even down to a 26 if needed. Have you ever kicked around the idea of running a full slick on your car?

I like having good brakes. Smallest that will clear them is 18" on the back (Gen 3-5). Even when I trap 150, I'm able to stop at the first exit opening, without a 'chute. My car is primarily a street car, and it sees 200 a few times a year. Needs brakes for that :)

ArrestMeRed04
11-21-2013, 07:38 PM
I was planning to just remove the rear brakes altogether for trips to the track.