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View Full Version : Wheel Hop during launch, drag racing?


BlackZenkiS14
06-07-2012, 03:50 PM
So I went to the drag strip, and my car wheel hopped like crazy. I have aluminum subframe spacers, all adjustable links, tein coilovers, and a Cusco 1-way diff...

What else can I do to cut down on wheel up when launching at the drag strip?

I was so frustrated with my time, I am completely plagued by the 13's. I went 13.01 @ 111 multiple times. I keep cutting like 2.2 and 2.1 60's. Cut 1 2.0, but missed a gear. I know the car can do 1.9's I just gotta get it down!

locoluna825
06-07-2012, 04:20 PM
Didnt think were coilovers are a good choice for those wanting to make better 1/4 mile times....? I thought that you needed softer suspension in the rear for that.

jr_ss
06-07-2012, 05:25 PM
Get rid of your spacers and put solid bushings or new bushings in. Me thinks your subframe bushings are toast and you'll still see wheel hop with spacers.

boosted KA24DE
06-07-2012, 05:52 PM
^+1 on that after doing solid bushings car just tucks and moves. No matter what kind of spacers you choose , if the oem joint are toast you are wasting your time. leave coils on full soft and do not preload springs.

turbociv910
06-07-2012, 08:42 PM
you guys couldn't be more wrong with leaving coils on full soft.

LuckyX2
06-07-2012, 09:09 PM
you guys couldn't be more wrong with leaving coils on full soft.

Care to explain? You want some squat, don't you?

jr_ss
06-08-2012, 04:51 AM
you guys couldn't be more wrong with leaving coils on full soft.

You have no idea what you are talking about. Go back to your Honda.

BlackZenkiS14
06-08-2012, 07:04 AM
+1, you would only want stiff rear on a honda....or FWD car.

I ran my coils at full soft, I know the game, I just need to figure out how to eliminate wheel hop.

LuckyX2
06-08-2012, 07:31 AM
You have no idea what you are talking about. Go back to your Honda.

Lol yeah, I figured he was confusing FWD and RWD.

FWD you want the rear stiff so it doesn't squat and lift the weight on the front tires. RWD you want as much squat as you can to put weight on the rear tires. I just thought I'd give him a chance to realize that on his own tho.

But back to the topic of wheel hop...
How's the surface at where you're dragging? I'm no drag pro by any means but that would affect wheel hop, right? What tire pressures are you running? what rpm are you launching at? What size/model tires do you have? Do you have the rear stripped?

And seconded on the solid bushings. Just don't put any of the shims in if you go with something like SPL. That will decrease your squat.

BlackZenkiS14
06-08-2012, 08:09 AM
Lol yeah, I figured he was confusing FWD and RWD.

FWD you want the rear stiff so it doesn't squat and lift the weight on the front tires. RWD you want as much squat as you can to put weight on the rear tires. I just thought I'd give him a chance to realize that on his own tho.

But back to the topic of wheel hop...
How's the surface at where you're dragging? I'm no drag pro by any means but that would affect wheel hop, right? What tire pressures are you running? what rpm are you launching at? What size/model tires do you have? Do you have the rear stripped?

And seconded on the solid bushings. Just don't put any of the shims in if you go with something like SPL. That will decrease your squat.

Surface is concrete with VHT applied after water box. I dont go through water box.

I ran 30PSI in 255/40/17 Falken FK 452's. Launch at 4.5Kish, back of the car is stripped minus the cage, nothing in trunk but battery and sub.

jr_ss
06-08-2012, 08:22 AM
Do you slip the clutch or dump it? Preload suspension drivetrain at all?

BlackZenkiS14
06-08-2012, 08:24 AM
Definitely slipping the clutch, Not sure what you mean by preload the suspension drivetrain?

LuckyX2
06-08-2012, 08:33 AM
Surface is concrete with VHT applied after water box. I dont go through water box.

I ran 30PSI in 255/40/17 Falken FK 452's. Launch at 4.5Kish, back of the car is stripped minus the cage, nothing in trunk but battery and sub.

You can and should go lower than 30psi. Having such a light rear isn't helping things either. Can you move your seat back a little further? Where are you at HP wise?

BlackZenkiS14
06-08-2012, 08:46 AM
I dont want to go lower than 25psi on the tires, they arent drag radials lol. They are Z rated street tires.

But My seat can't go back further with me being able to effectively control the car.

HP is probably at 280WHP if I had to guess...maybe 300.

LuckyX2
06-08-2012, 08:58 AM
Well yeah, I wasn't talking about 10psi or something ridiculous, just something a little better than 30 like 20-25psi.

That's just a band-aid until you take care of the subframe bushings tho. That's pretty much THE cause of wheel hop, worn suspension bushings/components. Plus, those spacers you have in now are reducing your squat.

jr_ss
06-08-2012, 11:47 AM
Definitely slipping the clutch, Not sure what you mean by preload the suspension drivetrain?

Pull your ebrake then let your clutch out slightly, you'll feel the car load. Hold it there until your launch. Obviously you'll need to drop ebrake as you launch, just make sure your car is in gear. I honestly think you need to slip more, you shouldn't be wheel hopping out of the gate if your doing it right. I was pulling 1.9 60s on street tires and the only way I would see a bit of wheel hop was if I screwed the launch, i.e. too much throttle/ not enough slip.

You need to get the rear suspension addressed though. It's not helping your cause.

S@nt0s
06-08-2012, 01:21 PM
Lol yeah, I figured he was confusing FWD and RWD.

FWD you want the rear stiff so it doesn't squat and lift the weight on the front tires. RWD you want as much squat as you can to put weight on the rear tires. I just thought I'd give him a chance to realize that on his own tho.

But back to the topic of wheel hop...
How's the surface at where you're dragging? I'm no drag pro by any means but that would affect wheel hop, right? What tire pressures are you running? what rpm are you launching at? What size/model tires do you have? Do you have the rear stripped?

And seconded on the solid bushings. Just don't put any of the shims in if you go with something like SPL. That will decrease your squat.

Sorry boss but thats not true, Look at any of the big HP drag cars on IRS Mustangs, Vetts' Vipers they have little to no squat. 240's,Supras,RX7's have a lot of squat but its at a lost. the energy lost from squating shouls be transfering to the wheels not lost in suspenion.bosy movement.

OP lower your tire PSI to 15-20 and dont launch it so high, drop your revs down and slip the clutch. the high PSI in the tires and high launch is causing a majority of the hop issue . check your bushings too as they could be worn.

LuckyX2
06-08-2012, 01:36 PM
It was my understanding that you want some squat to transfer weight to the rear. This is incorrect? I understand what you're saying about energy being lost to the suspension but it is minimal, no? Once you get past the initial launch and compression of the rear suspension, you're not losing any more energy. At least that's how I see it.

If all the big power guys are running with minimal squat and it's working for them then I guess it must be right. That's on drag slicks though, I assume. Drag slicks have enough traction that you don't need to squat as much. It seems logical that you'd want more squat on street tires with less grip.

S@nt0s
06-08-2012, 01:48 PM
It was my understanding that you want some squat to transfer weight to the rear. This is incorrect? I understand what you're saying about energy being lost to the suspension but it is minimal, no? Once you get past the initial launch and compression of the rear suspension, you're not losing any more energy. At least that's how I see it.

If all the big power guys are running with minimal squat and it's working for them then I guess it must be right. That's on drag slicks though, I assume. Drag slicks have enough traction that you don't need to squat as much. It seems logical that you'd want more squat on street tires with less grip.

some yes but not like this
http://i88.photobucket.com/albums/k173/toyotaterrorist/IMG_1880.jpg

these guys have so much power they can do that LOL. but its lost motion plus a 28/10.5 helps lol

these here are Mustangs IRS on DR's
http://i17.photobucket.com/albums/b97/TheHolyCobra/Track%20Pictures/93043_zoomed.jpg

http://i17.photobucket.com/albums/b97/TheHolyCobra/Track%20Pictures/DSC_0045Resized50_zoomed.jpg

see the difference in suspension travel

LuckyX2
06-08-2012, 01:53 PM
Oh well yeah, I didn't realize we were talking about wheelie levels of squat lol.
Obviously you don't want that. OP is under 300whp, has coilovers in the rear (which are presumably stiff) and squat reducing subframe spacers so I doubt there is a ton of squat going on.

It was my imagining that he was squatting very little and in that case could use a little more. I do agree that you don't want much more squat than those mustangs you posted tho.

OBEEWON
06-08-2012, 02:34 PM
Dude is right about the full soft thing. At least with dampening. Sag your springs. Full hard. Take some castor out your traction rods. Drop tire psi and pray for rain.

Factory bushings for the sub frame would help too.

jr_ss
06-08-2012, 03:32 PM
IRS squats, no matter what... It's going to happen. Sure you can limit the amount it does to an extent, but you can't prevent it.

S@nt0s
06-08-2012, 04:40 PM
IRS squats, no matter what... It's going to happen. Sure you can limit the amount it does to an extent, but you can't prevent it.
never said prevent as a solid axle has some squat too , downward force/gravity will always win but it can be countered to help and minimize it.
Im stuck with stock suspension for now and will push that to its limit or whever i feel comfy with. in the meantime i will be building a nice custom rear set up with adjustable compression and rebound

jr_ss
06-08-2012, 05:19 PM
I've seen people running extremely low times very minimal suspension. Ivan's 9sec 240 didn't have any crazy suspension work done. Hks drag coils, and those things are spongy...

S@nt0s
06-08-2012, 06:47 PM
Didn't say it couldn't be done but it can be made better

tabasco122
06-08-2012, 06:51 PM
motor/tranny mounts can do it too. i have busted subframe bushings, but got delrin motor mounts and an alum tranny mount and i cut a 1.8 sec 60ft on street tires and an open diff. was pushing maybe 240-250hp. never got to run my car at the strip after the motor mounts, but the few times i launched it on the street there was absolutely no wheel hop.

jr_ss
06-08-2012, 07:02 PM
Street is no comparison for a prepped track... That shit is like tar paper.

tabasco122
06-08-2012, 07:05 PM
the car would wheel hop everywhere before the motor/tranny mounts...

AsleepAltima
06-08-2012, 07:16 PM
cars with tiny sidewalls dont give very much either. especially street compounds. when the tire cant give, it bounces. id definitely get a hold of a set of softer tires with more sidewall.

tabasco122
06-08-2012, 07:18 PM
hankook ventus rs3 is an amazing tire for the price...

boosted KA24DE
06-08-2012, 07:21 PM
I come from falken fk452's 245/40/17 on a 17x9 and experienced the same wheel hop of tires trying to grip. now on 255/35/18 on 18x10.5 and all that hopping is gone with some dunlop star z1 derizza tires. falkens were great for street but suck draggin and on grip. i would launch my car and spin till third lighting up my whole block. consider upgrading tires it helped me. star z1 tires are amazing compromise way better 615's had in the past. z1 start getting stick with minimal heat. I only tuck about an inch when i launch on pbm pro coils.

tabasco122
06-08-2012, 07:25 PM
the star specs are good, but as the tires get hotter they start to lose grip, same withe the kumho r comps. with the hankooks, the hotter they get the better they grip, they dont fade like the other brands. really is an amazing all around tire whether you are doing drag or autox

turbociv910
06-09-2012, 09:28 PM
false^.

msg length

tabasco122
06-09-2012, 09:33 PM
Top Tires: Grassroots Motorsports Magazine Articles (http://grassrootsmotorsports.com/articles/top-tires/)

codyace
06-09-2012, 10:30 PM
Run a slick, that'll keep er from hopping. Seriously. Unsure why these guy s are suggesting ultra performance street tires as an idea to get rid of hop when none of them remotely fix the issue.

Soft rear, and or slicks. Only way to fly.

boosted KA24DE
06-09-2012, 11:05 PM
Run a slick, that'll keep er from hopping. Seriously. Unsure why these guy s are suggesting ultra performance street tires as an idea to get rid of hop when none of them remotely fix the issue.

Soft rear, and or slicks. Only way to fly.
Not fix entirely but help! It takes a combination of things to fix the issue , we just here to give opinions of what has helped us from personal experience. but yes if its gonna be run on the track just run slicks. only problem he is gonna launch and bounce more from too much grip. he still under 300hp i'm talking from experience here.