Wheel hop 1-2 and 2-3 shift 1/8 mile drags

[sanguissaevus]

I'm getting pretty nasty wheel hop from 1st to 2nd and 2nd to 3rd gear shifts going down Redline Raceway 1/8th mile in Caddo Mills TX. Something like 5-6 hops from 1st-2nd and 3-4 hops from 2nd-3rd. Was hopping bad at launch but I lowered the tires to 17psi and it cured the launches hop but did nothing for 1-2 & 2-3.

Track conditions:
Asphalt 1/8th mile
no provisions to go around water box (must burn out)
81F, 56% humidity, DA 2638 ft.

Vehicle setup:
2000 RT-10
PS-2 tires a few years old at 17psi (probably need to be higher maybe 20-25 psi?)
drop in K&N's
Smooth tubes
3" catback no mufflers
Woodhouse motor and tranny mounts
Stock Koni's increased 2 half turns (All four of my Konis have max of 3 half turns. Don't know why.)
SnakeOyl adjustable sway bar links set to stock length
Black (+15hp)

Looking at maybe going to drag radials but not sure due to stock driveline. Also looking at maybe a taller tire to keep from having to shift to 3rd near the end of the track. Consistently 89mph trap speeds highest being 89.48. 345/35-18 maybe? Maybe Stiffer springs or max out the shock settings? Anyone else wheel hopping in 2nd & 3rd gears?

 

[-FROG-]

Through some of my research in the past, I found that wheel hop is what contributes to breaking half shafts, so be careful. I would back off the throttle a little till you find the sweet spot. A little seat time will help figure out the wheel hop a bit but I think suspension upgrades will be the best help. I want to say my GTS did it a few times at the beginning when I first got the car about 5 years ago, but after doing Eibach springs / caps, I forgot about it... I also went with drag radials back then too. Totally forgot I ever had any wheel hop...

 

[sanguissaevus]

Sounds like a good plan. What size and type drag radials did you choose? I was looking at bfg 345/30-18 and mt 345/35-18. I was interested in the 35 profile mt to keep me out of 3rd gear in the 1/8th as im shifting into it very near the end of the track. Im a touch worried worried though my launch rpm will be so high with these that i will break the diff or the shafts.

 

[-FROG-]

Here's some old notes from back in those days I posted on the Alley........ First outing was an 11.5, then went back and got 11.35 @125....

http://www.viperalley.com/forum/viper-discussions-gen-i/76991-frogs-98-gts-1-a.html

http://www.viperalley.com/forum/viper-discussions-gen-i/90858-frog-s-98-viper.html


Not an ideal time to go to the drag strip... We all know HEAT is the enemy when it comes to racing or trying to reach a speed goal. It was 105 degrees when we left the house in Austin and 105 on the highway before we pulled into the track at San Antonio Raceway. A friend of mine said his girlfriends car

You must be registered for see images attach

, out in the parking lot in Austin, read 111 about the same time we left to go to the track. My goal originally had been for a high 11 because this car felt faster than my RT/10 that ran a 12.1, but ideally with this heat, I was more expectant of a low 12 second pass if things went well...



However... Viper came though!!!



-------------------------------------------------------------------



Here are the details for any of you interested or wanting to know more about my setup.



When I installed my Eibach Springs a few months back, I adjusted my shocks. My shock adjustment settings are as follows... First tighten the shock at full tight (clockwise).... then backed off to:

Front - 1 full turn back off

Rear - 1/2 turn back off



I had my rear tires

You must be registered for see images attach

" 345's - BFG G-Force Drag Radials" on 18" HRE's, at 22lbs of pressure. There was ZERO tread, so only sticky flat surface left, which is good... BUT, I BARELY had any tire left in the rear at all and needed to make sure I could make it back home (about an hour drive) so I couldn't go ALL OUT with burnouts. I think smoking the tires would have netted me better results but I just couldn't do it. I basically went around the water box as much as possible and did a few clutch dumps to dry the tires off. I tried to launch around 4000RPM's and since I was on drag radials, I could pretty much get into the gas fairly quick off the line.



For my shift points, I upped my shift light to 5700RPM because the Dyno showed some power left at the top (my RT/10, was set at 5200, so trying another shift point in this car).



I didn't really ride the clutch out this time, like I did with my RT/10, so after the launch, it was gear bangin time!



Results - VIDEO Below:
http://www.youtube.com/watch?feature=player_embedded&v=IuYkULeO1zE


I'll try to post a video soon. Here is the info below from tonight at the drag strip. I'll mention my mods, in case folks find this post in the future doing drag race searches on here, and my mods in my sig change in the future. I'll also list other important data for folks interested in specific details, like me. I did not do a "full", smokey burnout... Only a quick high rev and then dump the clutch to spin the tires HARD and get the water off my tires.

Mods for this pass are as follows:
98' GTS with 01' "Creampuff" motor swap
A.R.T. Dyno puts my car

You must be registered for see images attach

at 455HP / 499TQ (I actually lost a few HP after installing the roller rockers. Before the after market RR's, was 461HP / 507TQ)
SVT "Race" Headers
No Cats
Side Borla mufflers (no rear mufflers)
Eibach springs & Lowering caps
Raptor shift light
Aluminum Fly wheel
A.R.T - SCT Tune (93 octane pump gas)
Harland Sharp Roller Rockers 1.7 (got these used, not brand new)
K&N filters
Smooth Tubes
BFG Drag Radials 345/35/18
Removed spare tire & Jack

Track temp - 70 degrees.
Approx 700ft elevation in San Antonio TX
Car weight, with driver included, on track scale - 3,485.
60' 1.76
1/8 - 7.39 @ 97.74
1000 ET 9.5
1/4 mile - 11.35 @ 125.00

I'm VERY Happy with this time, considering the few mods I have. I was hoping to get closer to a 10 sec pass, and feel like I could have done a little better, but I didn't get many runs in and didn'd have enough tire to do GOOD burnouts (as usual, lol)).... Other two passes were 12.1 @ 108 (eh... blew the tires off, at the launch), and 11.7 @122 (spinning hard in each gear, had to let off the gas, temp was 65 degrees at this point). This should have been a GOOD ET because it was getting cooler out car was moving FAST, but just had no traction).

Had a blast tonoght! Hope this info helps you guys out!

 

[sanguissaevus]

Very impressive and very helpful! I've got a lot more practice to do before I can even come close. If I don't kill this wheel hop though my practice time will come to a screeching halt.

I watched all the vids of you racing and the one that I could get a good look at your tires made it look like you were running a 345/30-18 instead of a 345/35-18 (the sidewall looked low profile). I looked up BFG drag radials but couldn't find it in 345/35-18 but did find it in 345/30-18. Was this a typo? Did you mean to write 345/30-18 instead of 35? Mickey Thompsons ET's come in a 345/35-18 though. I'm very interested in this detail because of the effect on the final drive ratio it has. In my situation, running a 35 profile instead of a 30 might keep me out of 3rd gear in the 1/8th mile.

I haven't tried shifting below redline. I've heard of this but never tried it. How does it compare to shifting at redline in your experience? I'm mean, what would the time slips reflect?

Again, good stuff and thanks again for all the great info. Have you been racing recently? I noticed you have a Paxton now. Were you able to hit 10's before the Paxton? I'm sure you could hit it now with the way you're driving.

 

[-FROG-]

Sorry, yea, they were 345/30-18 and HOOKED like a ****. I'm now running Nitto 555 335/35-18. They hook amazing on the street but I noticed they weren't as sticky as the BFG's at the drag strip. I lost a few tenths last time I ran with these tires but some of it may have been due to the height.... although they weren't as hard hitting out of the hole as the BFG's were.

About shifting below redline... many people do it. Your can may roll off on power at redline, so shift sooner.... Many people actually even shift at different points depending on what gear they are in... for example, 1-2 shift at 5,800, 2-3 shift at 5,900 and 3-4 shift at 5,700. Not sure exactly but you get the idea... Cars don;t always max on power till redline... typically it;s best to shift sooner. At least that is my experience as well. A RAPTOR Shift light helps ALOT for drag racing... set the light to come on when you want to shift and all you do is watch the road. Safer too in my opinion.

I haven;t had my car to the track for a few years or so... since back when I made those videos / threads. The closest I got to 10's was my 11.3 but I think the temperature was in the 80's that day. So if I were to be running in the 60's, I may have been able ot shave a few more tenth's off and make some magic happen, but the nearest track is about an hour drive, so I don't get to go there much. Now, I would say 10's would be ideal, although I am only running at 2#'s of boost on my current tune at about 502HP. I had a few bugs I worked out after my last tune and need to get it tuned again... it's just not running anywhere near where it possibly can at the moment but it's a cast motor so just trying to be careful with my engine at the same time.

 

[sanguissaevus]

Cool. I did the math for my dyno sheet and my current set up suggests I should 1-2 shift at 6,000, 2-3 at 5,900 and the rest at 6,000. Not a big change but I will drop my rpm at 2-3 by 100 non the less. I checked how a 35 series tire will effect gearing and it will raise my 1-2 shift to 60mph and 2-3 to 91mph and 3-4 to 114. This would get me out of shifting to 3rd in the 1/8th but if it were on stickier drag radials I would probably end up shifting into 3rd anyways due to quicker 60 foots and and less to no wheel hop shifting. Decisions, decisions.
My track is only 15min from me so I am very lucky. This is why I'm focusing on the 1/8th instead of the 1/4. There are 2 great 1/4 tracks here but the closest is an hour from me as well. I plan on going but not till I can sort out these things on the 1/8th.