Assuming 3600lb raceweight, front swaybar and 'regular' wheels up front?

What about with skinnies? and no front swaybar?

Just curious about at what point you started lifting a tire at the track. I'd like to...someday <img src="gr_images/icons/wink.gif" border="0">

Dope

 

For my bolt on car at a 3350# race weight, no front swaybar, and skinnies I pull the wheels at around 1.58 and under. <img src="gr_grin.gif" border="0"> And with the front Hals, I get great wheelwell/tire separation which makes it look like you pulled the wheels more than you actually did. <img src="gr_images/icons/wink.gif" border="0">
<img src="graemlins/camaro.gif" border="0" alt="[Chevrolet]" />

later,
Steve

 

It all depends on your specific setup... There's no magic number here for picking up the front tires...

 

Has alot to do with your suspension setup. Even now running low 1.4s I can almost keep my front tires on the ground by stiffening the front shocks all the way up.

 

My car has carried a wheel on a 1.61 60ft. That was 100% stock suspension minus the front swaybar (car was two months old <img src="gr_images/icons/wink.gif" border="0"> )

I finally got it on film with a 1.59 spinning....

 

it looks like its about a 1.62 60' is where you can start lifting the wheels. i was cutting 1.55s and did not, mainly cause i had my suspension setup not to <img src="gr_stretch.gif" border="0">

 

crap i'm only at a 1.907 right now <img src="gr_emb.gif" border="0">

 

i cut a 1.44 and did not lift the wheels. my suspension works against that

 

Hehe, looks like I have a ways to go <img src="gr_stretch.gif" border="0">

2.15 60' being my best *snicker*

Dope

 

another worthless post from no-rain-boy... <img src="gr_images/icons/wink.gif" border="0"> <img src="gr_tounge.gif" border="0">

with a travelin suspension, ive seen a 1.77 pull a tire. with a stock suspension itll take another tenth and a half to pull one (NO swaybar and skinnies). but thats all fuzzy math.

 

RUQUICKR, had a pic of him lifting a tire with a 1.7x 60ft. <img src="gr_eek2.gif" border="0">

 

I wonder If I could lift them off of a T-brake with stock suspension.... <img src="gr_stretch.gif" border="0">

 

I used to do it back when I was stock with mid 1.6's.

That was with no rear air bag or bigger rear say bar. (completely stock suspension minus the front sway bar)


LOW 1.6's? "popping" the front left could happen. (IMO)

Personally I try REAL hard NOT to lift the tires. Or to just barely lift them. It's just wasted energy. IMO

 

Hello... I have a V6 and cut a 1.6 60' on nitrous spraying a car out and ran 12.3...

I was talking with Pro Stock John a little about suspension, weight transfer and soft shocks in front. We discussed a little bit about soft HAL shocks in front to help transfer the weight..

I always thought, a lot of suspension movement is wasted energy but now I only feel that way about the rear. In the front, if you do pull the wheels, even a foot or so, the energy pull up the car could have been used to push the car forward. Yes, but what about when the car is coming back down. The weight of the car coming down will make up for the energy it took to pull it up, right?

Lets say you have a tight suspension in front, you flash your converter and the front only comes up a little. The engine has to work harder to push the car forward but if the front end came up easier, the engine would rev up faster and you would also accelerate quicker, right?

Can anyone get a little more techincal about this? Like why its wasted energy if the front end is moved up? (lets assume rear is stiff and has no movement)

Thanks. I'm wondering if I should purchase some HAL's to help drop my 60'.

 

[quote]Originally posted by Magnus:
<strong>
In the front, if you do pull the wheels, even a foot or so, the energy pull up the car could have been used to push the car forward.
</strong><hr></blockquote>

Seems reasonable to conclude that...

[quote]
The weight of the car coming down will make up for the energy it took to pull it up, right?
<hr></blockquote>

I don't think that gives anything usable back. The energy is returned on a vertical axis, you want as much energy as possible applied to the horizontal axis (i.e. going towards the finished line).

I've seen low riders bounce up & down on the street without going anywhere fast.

 

To answer the original question, I'd say mid 1.6's you will see folks pulling a tire. Higher than that and they don't have enuff traction really.

----

We don't want to have the front wheels 3 feet off the ground.

But we want excellent traction. But as we modify our cars to cut 1.5's, then 1.4's, 1.3's, you get to the point where folks start to use suspenion limiters, wheelie bars, and other items and methods to keep that 1.3 60 ft but keep the front of the car down.

Some really fast cars are so fast that the car does the first half of the run on the back tires and the wheelie bars.

I don't think it's possible to cut a 1.3 and keep all four tires on the ground at the launch.

 

Here is another angle.

The rear tires. They just turn. They want to go forward. If the twisting motion of them is great enough to lift up the front, then the wheels are free to move more forward... but if the front won't let itself be lift up the wheels need more energy to move forward.

Don't think of it as pulling the front wheels of the ground.. Rather think of it as the rear wheels moving forward.

 

I only want the front end to come up enough to ensure near perfect traction. Anything more than that is wasted energy.

I agree that the energy of the front end falling back down is not returned to the drivetrain for the most part and thus helping to propell the car forward. You are better off for the tires never to leave the ground (again, assuming traction is maintained.) In a perfect world where traction is always perfect, neither the back or the front suspension would ever move and ALL power would be utilized in propelling the car forward.

Unfortunately, I am finding so far that I need the extra weight transfer to get traction so I am not takeing steps to limit front end rise...yet. I am working towards the goal of being able to have both traction and much more limited front suspension movement.

 

Picture this....

Instead of tires, they are geers.. and there are 2 lines of teeth in the strip.. so there is NO slippage at all.

You flash your converter.. your car moves forward. Those gears want to go forward as fast as possible. The fact that they are moving forward at a very rapid rate... makes them want to move underneath the car.. ie: lifing the front up.

If the front end is restricted from rising energy is lost because it will take MORE work for the gears to go forward.

But say that the front end does come up... the gears will be able to move themselves forward with ease...

Now I bring you back to the increased angle. As the front end comes down, it will twist the rear and make up for what was lost from the down/up motion in distance.

 

Power is transfered from the engine, through the trans, driveshaft, converted in the differental to a twisting motion at the tires.

The front travels upward because the axle spins itself forward. If the axle has to fight the front end, power is lost.

Any physics guys out there understand what I'm saying and/or can help me understand a little better?

Lets keep our analasys below ... lets say 30 degree incline.