I can't get it to go straight down the1/4 mile track. 99 Viper, Roe, Water ****.

[King RT10]

A lot of Vipers with a lot more horsepower are doing it saftley from the boards.
Now my car has either bad wheel hop, where I have to let off. Or worse when I shifted to second gear on a hard run, I spun out into a 180.

So what do I need? I have Kumo's on a stock rear rims now. But zero confidence that I could make it saftly down a 1/4 mile track.

Unless I granny shift/ drive it similar, to a 20sec 1/4 mile time.

Any tips on tires or suspention. My gear is a 3.55, which is fun for around town.

Jealous racer in Florida for years...

 

[uvbnbit]

I think I've read new motor mounts and tranny mounts help with wheel hop.
What PSI you running in the tires?

 

[viper04]

King
What kind of power is the car making?

 

[King RT10]

Circa 630 at the wheels.
What PSI should be in the Kumo's

 

[FastMatt]

Start by adjusting your shocks there most likely on the softest setting. My car had really bad wheel hop in the stock settings.

When my car was just heads/cam it made 612 rwhp and I was running 3.55 gears and ran 10.7@130-131 on slicks and 11.0@132 on 19" street tires

 

[Mopar Boy]

Yes, shocks are very important. That will be the best start.

Second question may be stupid, but how old are the tires?

 

[uvbnbit]

which kumhos? v700? exsta xs? I'd guess 20-22psi?
what about track prep?

 

[99 R/T 10]

I think I've read new motor mounts and tranny mounts help with wheel hop.
What PSI you running in the tires?

^^^^^^this^^^^^^^^

If you haven't replaced them since you have owned the car, you can bet they are trash. Get some Woodhouse mounts.

 

[00SVTdubs]

buy my CCW slicks and skinnies for $800 shipped.. problem solved.

 

[Roysviper]

buy my CCW slicks and skinnies for $800 shipped.. problem solved.

And that is a steal......I would never take that for mine........If you have not changed out the half shafts yet, you will be......I always use the UNITREX half shafts.....I have never had wheel hop in a gen 2 viper......and also I use M/T street radials.......with 30 lbs of air........AWESOME traction

 

[jwolf]

Mine had wheel hop till I put in Woodhouse motor and trans mounts, I found one of my motor mounts was broken.

http://youtu.be/ziaViIlkUZg

http://youtu.be/ji795oJ5pv0

 

[alwayscode390]

Awesome vids, thanks ---

 

[rw99]

Get some drag radials on that car, ASAP! M&H or Mickey Thompson.

 

[Mad Max]

I have wheel hop in my Gen II. I changed to the Woodhouse mounts and still have the hop. Not quite as bad however it is still there. I'm afraid to up the hp until I get it under control.
Good luck getting your Viper to run straight.

 

[King RT10]

I have wheel hop in my Gen II. I changed to the Woodhouse mounts and still have the hop. Not quite as bad however it is still there. I'm afraid to up the hp until I get it under control.
Good luck getting your Viper to run straight.

Right! I do not need more Horsepower until it goes straight.
Are there any pictures of MT street radials on a Gen2 Viper? Will they fit on a stock 1999 rim?

 

[slysnake]

Man!! I had a freekin' heart attack when the camera fell over in the second vid. lol

 

[Jack B]

IMHO at 600 hp kUHMO'S are a very poor choice for straight line acceleration. They are great for track or autocross, but, they are the worst tire I have had on my car at the drag strip.

 

[Mopar Boy]

Watch it! Camera falling.....

Thanks for the video. Shows a good idea of what is involved for those that have not ever changed mounts.

 

[jwolf]

My motor is stock and the mounts took care of the hop.

 

[Dom426h]

A few possibilities that i can think of:

1. Your reaction time is to slow to compensate for the rear end by reacting with a precise countersteer in the right direction
2. Your brain is not able to effectively communicate with your hands to tell them how to correct the situation
3. Your alignment could be out of spec and not optimal for drag racing.
- Stock spec alignment should be fine and for a 1/4 mile car i wouldn't go more than .5 camber in the rear.
- Slight Toe IN in the rear is crucial to keeping her going straight whether it be on a drag strip or road course.
-If you have any Toe out on the front or rear then i am pretty sure you are asking for trouble.
- Others more experienced with dragracing might have more input on this than me. Sure most think its all about power and tires. But the experienced know that alignment & suspension setup is important as well.
4. You could be shifting too hard, or rather releasing the clutch to abruptly and/or applying the gas too abruptly causing a lose of traction.
- when releasing the clutch(shifting to 2nd) try to initially apply the throttle at 90%, rather than having your foot to the floor at 150%
- spinning tires between shifts any more than a slight chirp is detrimental to your 1/4 mile time.
5. a combination of the above


Goodluck, and let us know what you change and how you make out.

 

[Dom426h]

To the "you need stickier tires camp":

I don't care how old or ****ty your tires are. You shouldn't be spinning a 180 while shifting to 2nd going down the strip. Period.

I'm a road racer. If someone showed up to a track day and was consistently spinning out in turn1 then i would instruct him on how to safety&correctly maneuver through the turn with proper technique. The last thing that would be on my mind would be recommending r-comp tires to him. Sure if he had some sticky r-comp tires on then he might not spin out on that turn, but now he is able to go faster and faster until he then spins out again, Only this time the increased speed results in increased danger as he spins off course and into a tire wall. Now if he learns how to control his vehicle at the limit on street tires and gains enough experience to successfully recover when going just a hair past the limit then he will be a much faster AND safer driver when he upgrades to r-comps.

Now apply that story to King. Say he does put some sticky tires on there and can put a nice time down getting down the track successfully. Some time in the future he might decide to up the boost or convert to TT resulting in a significant amount of increased power. If he still has poor technique, bad alignment, ect... then bad things will eventually happen.

If fundamentals do not come before FAST then the likenesses of Danger will increase.




(no offense King, i know nothing of your experience and my comments are in general to promote safe motoring)

 

[rw99]

To the "you need stickier tires camp":

I don't care how old or ****ty your tires are. You shouldn't be spinning a 180 while shifting to 2nd going down the strip. Period.

I'm a road racer. If someone showed up to a track day and was consistently spinning out in turn1 then i would instruct him on how to safety&correctly maneuver through the turn with proper technique. The last thing that would be on my mind would be recommending r-comp tires to him. Sure if he had some sticky r-comp tires on then he might not spin out on that turn, but now he is able to go faster and faster until he then spins out again, Only this time the increased speed results in increased danger as he spins off course and into a tire wall. Now if he learns how to control his vehicle at the limit on street tires and gains enough experience to successfully recover when going just a hair past the limit then he will be a much faster AND safer driver when he upgrades to r-comps.

Now apply that story to King. Say he does put some sticky tires on there and can put a nice time down getting down the track successfully. Some time in the future he might decide to up the boost or convert to TT resulting in a significant amount of increased power. If he still has poor technique, bad alignment, ect... then bad things will eventually happen.

If fundamentals do not come before FAST then the likenesses of Danger will increase.




(no offense King, i know nothing of your experience and my comments are in general to promote safe motoring)

Agree 100% with your final statement. But with respect, we're talking apples and oranges when it comes to spinning on the road course and losing directional control at the drags. The OP had an episode of lost traction on an upshift in a high-powered car, not an improper line through T7. Technique for saving the instantaneous loss of traction at the drags? Boy, get out of the throttle and hope you have fast hands. The worst crash I've seen while drag racing was a guy (in a Vette, chuckle) that believed he could stay in the throttle and push the car back on line... resulting in a pinball game from K-wall to K-wall. And 45 minutes of waiting for those of us in the staging lanes.

While poor track prep and/or a fluid leak on the dragstrip surface are possible causes, we're focusing on the OP's inappropriate tires and noted wheel hop... both of which contribute to his control problem. Proper suspension setup (alignment & weight transfer), drag radials and/or slicks, and the above suggestions re: trans/motor mounts should fix this problem. Speaking of which, I know that there are some "hop-not" kits for other IRS cars... anyone know of one for the Viper?

Also a good suggestion to upgrade the halfshafts, because once the car starts hooking hard there's probably a broken halfshaft in its future...

Best of luck,

Rich

 

[King RT10]

A few possibilities that i can think of:

1. Your reaction time is to slow to compensate for the rear end by reacting with a precise countersteer in the right direction
2. Your brain is not able to effectively communicate with your hands to tell them how to correct the situation
3. Your alignment could be out of spec and not optimal for drag racing.
- Stock spec alignment should be fine and for a 1/4 mile car i wouldn't go more than .5 camber in the rear.
- Slight Toe IN in the rear is crucial to keeping her going straight whether it be on a drag strip or road course.
-If you have any Toe out on the front or rear then i am pretty sure you are asking for trouble.
- Others more experienced with dragracing might have more input on this than me. Sure most think its all about power and tires. But the experienced know that alignment & suspension setup is important as well.
4. You could be shifting too hard, or rather releasing the clutch to abruptly and/or applying the gas too abruptly causing a lose of traction.
- when releasing the clutch(shifting to 2nd) try to initially apply the throttle at 90%, rather than having your foot to the floor at 150%
- spinning tires between shifts any more than a slight chirp is detrimental to your 1/4 mile time.
5. a combination of the above


Goodluck, and let us know what you change and how you make out.

I will have all the mounts checked. They are stock. If I gun it from a roll the whole car bounces.
When It spun after 2nd gear it felt like speed wobbles. One tire grabbing then the next, into a wabble. It has happened before but I saved it from spinning. It did not feel like driver's error as I have raced cars for decades in a straight line.

I thought Kumos were supposed to be great for straight line acceleration??

 

[brentsGTS]

try building your way up next time you go. instead of running it full out, launch and drive it like your at a street light. roll into the throttle and when you shift, dont dump the clutch and slam the throttle, instead step out of the clutch and step into the gas. your times will be alittle slower at first but you can then "learn" your car and see what it likes and doesnt. every car is different. a slower time is better than spinning out and possibly causing a crash or worse.

 

[Camfab]

As Stated check mounts, then check torque on the bolts that hold the Diff in place. FYI my car did an abrupt 90 degree right turn while trying to execute a burn out on Sport Cup tires with ****ty track prep. Wheel hop is going to destroy your axles, if they haven't already been compromised. My guess is that the hard right turn deal I experienced was probably due to poor track prep as well as cold tires and an inferior limited slip design (Trak Loc).

 

[BigBadViper]

Is it possible that something could be wrong with your diff causing the one tire to spin before the other. I know that it is limited slip, but... If one tire has traction and the other doesn't that might cause a 180 spin. As far as wheel hop, that could be motor, transmission mounts, and shocks, as far as just spinning all the time you need stickier tires. I have seen nothing better than the MT drag radials, I have them on a 97 and they fit fine.