FWD Wheelie Bars - Discussion

[bszopi]

After seeing a few more FWD 60V6 cars starting to get into the low 13s and quickly pushing the 12-sec. envelope, I figured we might get into a (civilized) discussion as to what people think about wheelie bars on a FWD car.

To start off, here is my first link for discussion:

http://www.theoldone.com/archive/physicsbehindFWDwheeliebar.htm

As I stated, I want this to be a good discussion. If I see any threads that contain just stupid or ignorant comments, they will be deleted. Although most people will never think of doing this, I think there are people out there that just might be willing to try the idea out.

So let's go with that...

[1QUICKHATCH]

I can see it helping out a civic because of the short wheelbase but not so much with a J, L or w body. in that link they talked about reducing the rolling resistance on the car, you would think that would make it unstable in the top end???

[bszopi]

Interesting that you brought the stability issue up... Here is a short discussion about that:

http://www.eng-tips.com/viewthread.cfm?qid=76589&page=5

And as far as using them on a larger car...

[bszopi]

And, from an NHRA Magazine article...

"Bergenholtz earned his nickname when he and his brother, Ron, reinvented the wheelie bar and then broke the 10-second benchmark in the quarter-mile. Wheelie bars are like car training wheels. They trail behind a dragster, preventing it from tipping over backwards on launch. The Bergenholtz brothers put wheelie bars on their '89 Honda CRX - a front-wheel-drive car, which, by definition, cannot wheelie. On a front-wheel-drive car, the (now slightly misnomered) wheelie bars shift the center of gravity forward. They prevent the rear shocks from compressing at launch. This is, in fact, genius in its simplicity: Gain traction by planting the front end more firmly on the tarmac."

[Doubt_Incarnate]

They prevent the rear shocks from compressing at launch. This is, in fact, genius in its simplicity: Gain traction by planting the front end more firmly on the tarmac.[/b]"

I second that, the only reason i wouldnt just put steel rods in place of the rear shocks is for streetablity. otherwise if i had a drag only car it would have no rear suspension. maybe i'm stupid, but if the rear cant squat low, you cant shift the weight as much. on another note, when removing weight on a fwd, you want to start at the back. everything behind the real axel is dead, and whats in front of the front axle is whats going to help keep you planted.

[RacerX11]

The bars not only prevent the rear suspension from compressing, they effectively extended the wheelbase, which affects weight transfer more drastically than simply running solid shocks. The added ~20lbs behind the rear axle for the bars will more than pay for itself with increased traction.

I didn't read both of the links completely, but I think the biggest reason the serious drag cars have problems with steering at high speeds are 1) the bars are preloaded, 2) they run drag slicks, which tend to grow radially at higher speeds, effectively increasing the preload as speed increases, and 3) retractable wheelie bars aren't legal. So it is like driving with slicks on the front, and shopping cart wheel son the rear...not a recipe for stability, especially while braking.

Marty

[SappySE107]

HAHAHAHA! wow, that sounds like a lot of fun! Actually, there is a better way to go about this. Go RWD. Why can't we just raise the rear end of a FWD anyway? Sure, it looks retarded without the real rear end back there, but if it makes a difference without stability at a speed and time my grand prix doesn't really care about seeing...im down for looking like a redneck.

I think increasing the rigidity of the car will help out quite a bit. Not having a frame has to be an issue at some point.

[blackbombshell95]

and i'm glad ben's opinion isn't an order. phew

[RednBlack]

I had a thought about FWD Ladder Bars. The geometry would be a little tough, but...you know me. I'll toss out any question. For the sake of theory.

Another theory..You lean your engine forward as you would to change plugs, (if you do it that way). Change everything else to match. You have effectively increased your weight transfer, with no added weight.


Here is another question, Why do ricers put a wing on the back of a car that needs front downforce? I know! Wing on the front looks stupider..

[sharkey]

i can argue the wing thing to a point. i know when i put the factory spoiler onto my car it was more stable cornering at HIGH speeds (im talking 120km/h+). i have a friend that took his stock wing off his sunfire and at igh speeds, it wasnt as stable. however, a huge aluminum wing, a touring wing, or something stupid like a combat wing, they just do nothing but look stupid.

[RednBlack]

But, you said cornering. This is drag racing. Only 2 corners, in and out. Slowly......

Although Bens idea is redneck, planting front tires, when pulling, instead of pushing, I'm thinking....raise the back, stock size tires on back. Looks bad, but form follows function. Maybe lift panels? Strakes. (Under the car)


Talk about a "Funny Car". I wish I had the power to even think about this.

[asylummotorsports]

I have noticed that since I replaced my rear shocks with very stiff coil overs the car does launch somewhat better, however you do need some suspension travel in the rear even if the car is only used sparingly on the street.
Air bags might also be an option.
But solid rear suspension might actually be dangerous.
My .02

[XLR8ING]

Air bags work quite well for me. The car is MUCH more consistent in take off. 60' times are better on average, and the car spins less in second because of less weight transfer.
If I were doing a full out race FWD, I'd be using wheelie bars, but possibly in conjunction with a stiffer suspension already in the rear. I don't think I'd want so much preload on the bars, but I wouldn't really know until I did it.

[gectek]

I really like this thread. even though it is so old. i want to bring it back from the dead.

Reason being...I am looking at getting some KYB AGX's for my car to dial in the suspension for drag racing and then turning it back down for DD duty.

I know it isnt the same as wheelie bars though.

I thought, in theory, that you still want rear transfer of weight with the front end lifting up and the rear squatting, because you still ahve all that weight over the fwd tires. But in fact, i would need to stiffen the rear to keep it high and keep the front even stiffer? too bad drag bags are not an option with struts.
at least that i know of

[project89]

alot of guys around my local track have ditched the bars in favor of a really stiff rear suspension and raising the rear of car. at the same time they drop the fronts.

ive seen some hondas pull off 1.4-1.5 60's this way

the problem is some of these guys lower the front way to much theres plenty of clearance over the slicks when the car is at low speed. these guys run 5-7 psi in the fronts

but once they get down track the tire starts to grow, and when they hit the brakes after the traps the front end comes down so far it hits the slicks.

we had about 10 bad crashes this year cause of ppl losing control of there cars while getting on the brakes