The Cal-look Lounge

i couldn't help but notice on DDD that there are not too many cars anymore that do wheelies at the starting line... weird as the power of cars has greatly improved on cars over the years. so has everyone found the 'ideal sweetspot' that the car just accellerates forward and not upward? i can't really imagine that, but why no wheelies then?

Since you posted in the Pure Racing section I will give you a pure racing answer: Wheelies are show and no go. We have learned that if you want to go fast and at the same time save your drive train (and car) you need clutch control and improved weight distribution. But perhaps the answer to your question is traction?

-BB-

At least a few cm Mini Wheelie
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I think it is possible to have a combination of that  ;D ;D

MeXX

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Dear Kalle

I don't think so, as Gregor (PL) was able to run a 7,9 with his turboed Corvette

MeXX

OH YES... ;D

my car doesent wheelie and belive me ive tried everything to get a ego wall shot lol  :D but it does seem to do the trick so far 1.41 60ft and i believe with some more nitrous on the line it will go better ,it has no clutch control runs a stage 1 and black magic i just feather the throttle around 6-7k and drop the clutch and it hooks up squats like mad and off she goes  :D

i did indeed put it in the pure racing section for a reason. traction isn't the issue as i have seen wheelies in the past at DDD. and the question also remains as for more then 4O years beetles have been pulling wheelies and now i can't see the wheels come of the ground one inch. and traction, clutch-management, and what not has been an issue for more then a few racers in the last few years and now everything is solved?

that said there is not too much debate about the fact that a good launch doesn't need a wheelie, but it sure is a nice bonus  ;D

Fit super stiff rear shocks and take off the front ones, you´ll have your poster in no time.  ;D

BB, I agree.
Wheelies look impressive. But any time spent going up, is time not spent going forward.

lol im not bothered about the poster shot anymore  :D every tenth faster is closer to the single number et  ::) :D

How much power does one need to get a wheelie?   And what effect does it have to the front end when it comes down!?

I think you are all deluded, wheelies are great :o :D


 They are so much fun and make for a quality picture[yes not so much for ET ::) ]  The buzz from shifting into 2nd while the front wheels are still right up and carrying it out even further is up there with my 1st 9 and 1st 8, in fact its was proberly more fun as I knew what was happening at the time, with a real good pass you don't know till after as it almost feels boring

Nicolas, I can't comment on bitburg last weekend, but technology has moved on for sure and helped calm a lot of cars down to where they run quicker 60fts and 1/4 mile due to this

cheers Richie

as for the improvement, yes it can be technological welfare, but still, it can't get the idea out of my head that cars don't leave that hard. 60ft's will back this up or not, but i was surprised to see so few. not everyone can find that sweetspot just in a few year like this.

anyway, next year, we all do wheelies. no-one cares for 11's, 10's, 9's and even 8's. it's wheelies we want to see.



just planting seeds here.  ;D

Where's the "Like" button..  8)

 ;)

oh my gosh.
tell me about this ghia !!!

hahaha isn t this everybodies dream here having a street (cal look) car that does a wheelie.
Well it s mine at least..
Haven t been on a strip with my car yet  :-\. not the correct box yet.

regards edgar

   IMHO It is not so much about power , our 1776 bug will pull wheelies , but about suspension.  Stiff rear suspension , slicks  and real soft front suspension will allow weight transfer enough that it will pull the front off the ground. My previous car was differant with the turbo engine as seen on this video when the wheely bar support  bolts broke,

http://www.youtube.com/watch?v=FJZrEFElU24
          It felt good so I shifted second gear like Richie said.  Mike McCarthy

I'd love a cheeky wheelie in my car, but the way it was built and setup means that probably won't happen. 1.61 60ft on 205 street treads show its moving alright but the weight distribution and a calm launch means that that it just squats and goes.

Not quite as entertaining for the driver or crowds but it does the deed!

I think it was your car that scared me off wheelies  ;) :D

This is getting off the wheelie topic I know but it might be relevant so humour me ;)

 
So here's a question, why is it that its ok for it to squat? In my mind that's what we don't want, if it is "squatting" what it is actually doing is pushing the wheel away from the track upwards and into the car so then the car moves down creating the image of "squatting"

If the tyre or track is not sticky enough surely it will just spin the tyre and the suspension will hardly move? when it does what you are describing and then blows the tyre off surely its not working to its best ability?

I am only using your car as an example Rich,your post just got me thinking [ I know never a good thing!!! ] most of our type cars do it, but is there something we can do to improve that scenario? wouldn't you like more traction?  your mph suggests you have a 11second car that would wheelie as well :o ;D

If my ideas are even vaguely correct then the worse thing we can do to our cars is lower them at all at the back :o ??? ;)

cheers Richie

i don't think the squatting you discribe is actually the wheel going up and because there is gravity the car in reality comes down, but more a loss of forward power that pulls the car to the ground. if it was gravity alone, it wouldn't happen as it is too slow/not powerfull enough to do this to the car. so it must be the acceleration that causes this. wheelhop is pushing the wheel away from the track. the car will not sqaut. the squatting is the car that is inert and wants to stay where it is and the wheels just pushing it forward, hence the downward movement of the car (that is the visible outing where the lost power goes into).

Nicolas,

I cant see how any forces we apply to the tyre can pull the car down? the car is just there for the ride,

I have sent you a pm

cheers Richie

Come on guys, it's not that hard....

I agree

(http://images.thesamba.com/vw/gallery/pix/606480.jpg)

Its the mechanics of the ring and pinion that rotates the car against the power applied to it, when i pre load my circuit car it pulls itself down to the crouch position ready for the off, no forward motion at all,  once launched and going sky wards, with a light enough front,  inertia keeps it going up , best explained thus, try the same thing in reverse and see what happens, i would guess a reduction box bus would lift at the rear to some extent with the ring gear on the other side of the pinion shaft. hope that helps anyway.

The reduction box busses do lift in the back when accelerating.

I have a theory also.
This picture shows a neutral suspension.
the forces are on the springplate. The wheel finds traction and pushes the springplate. The springplate in turn pushes the car, which also pushes back with the same force on the springplate.
In this case the spring plate is balanced out
 (http://www.keversite.nl/fotoalbum/fotos/128277.jpg)
In the picture below the car is in a raised position which means the springplate is inclined.
Again the tire pushes the springplate en because the springplate pushes the car the car pushes back.
The difference is this time the forces are spaced by a distance over there line of work.
This distance creates a turning force of X Newton Meters on the springplate.
It wants to turn around. The tire can compress a bit and the rest of the turning force goes into lifting up the rear of the car. Because the car has inertia it will give more force on the tire aswell and give more traction
(http://www.keversite.nl/fotoalbum/fotos/128278.jpg)
If you set up you're car the other way around, lower it untill the suspension in the other way around the car will want to squat even harder than it always wants to do because of the diff like stated above by spanners.

If you think what happens to the forces when you actualy engage in a wheelie it will increase the traction even more by turning the springplates even more oposed toi the direction of force.

That is the main reason you dont want to squat to much, you need to keep above the neutral point

Thats cool!

Physics of Wheeliying:  ??? ??? ??? ??? ???

At first you need the torque to lift the front:

As common a beetle got 2400mm Wheelbase.

Maybe for example 300kg in the front. (approx. 3000N)

So you need 7200Nm to lift it. Lots of torque  ::)

If you calculate with a very common trans ratio of 3,78 first and 3,875 final drive the trans ratio will be 14,65.

so divide 7200Nm by 14,65.

That means you need 491Nm at the clutch to lift this . Without slipping tires or clutch.

Static.

In real life dynamics are different, e.g. weight transfer, as ratios and weights are.

But this is a good example, that its not that easy.

Don't you need to factor in tyre diameter as well?


cheers Richie

Jesse, that's a good diagram to show the basis of what happens, the other variable is the clutch and how hard it hits

cheers Richie

There also another part the length of the control arm and the height it is positioned this has a massive difference on traction/wheelie and getting it right off the line ( pls note I'm not talking from experience just what I've learnt from others lol) I find this subject very intersting as it's what will make a car work off the line.

 There are some very interesting on line calculators that model 4 link on a live axle it's interesting how the centre of the car changes just from changing the height of the control arms.  It's. A shame our cars don't work the same but it's interesting non the less.

http://www.motorsportsvillage.com/suspension1.html

Cheers Andy.

I dont think so.

The lever (Wheelbase) remains the same. Simple Maths

the mechanics of the geometry shown above are sound, and a good case for me to raise the torsion housing lol, ;) exactly as Porsche had to do with the 911, their trailing arms always angle down even on very low race cars, the technique of the launch on a race track , tho much different to a prepared drag strip, is the most important aspect, i line up against cars that should be crap off the lights and invariably get a shock as to how well they launch, any layout has a 'sweet spot' look at front wheel drive now days,  F1 cars with all their trickery can still make a balls of it,  but mine has reached the point power wise, where it needs electronics, , if i get it 500 rpm wrong it smokes the tyres, the same with the shift too second, i cant be clumsy with it. on the other hand, the very best swing axle drivers in the BBT cup cars use rear end squat to advantage, keeping the throttle nailed and there fore hunkered down at the back and into negative camber is the way to go quick round a circuit, true also with IRS cars but thats a lot 'tamer' in 'lift off' situations.

It's all about squat and anti-squat.
I've had full size sedan leaf-spring cars that only run flat 13s, but 60ft in the mid 1.5s.
The Ramchargers had it sussed really well in the early 60's. A Google on old-school slapper bar tech stuff will tell you more if you're interested.

And yes, following that old-school tech and experience, RAISING the rear of a Beetle (or at least the torsion assembly), using softer bars, and "drooping" the axle plates more in the set-up will probably be a bit quicker, definitely using limited traction tyres, you're using the weight of the car to leverage the tyres into the track on launch. Too soft and the top end might get a bit interesting though. It's all about instant centres and CofG's that someone with better drawing skills than I can share.

Since my Beetle is only going to run 16s and that's it, I'll let you guys try it all out though!  ;D
It's a science experiment!

Our cars DO behave the same way as a live axle, but with a difference.
Where a live axle can convert torque in to heaps and bounds of anti-squat, an IRS will only give you 25% of that anti-squat to play with.
Regardless if it's a swing or IRS, the chassis suck up a lot of the force, producing wheelies or whatever. The remaining 25% can be dealt with along the lines of a four link car, if you wish.

The normal Doorslammer book, comes just short to explain this, but Herb Adams Chassis engineering book has a pretty good section on the IRS and its workings.
Here is a link to the specific pages, if it works:
http://books.google.no/books?id=rY2ujnNrhf0C&pg=PA73&lpg=PA73&dq=Herb+adams+corvette++IRS&source=bl&ots=HfQuj8uU4x&sig=j8OuT_RUFRSOihZ7ZoXrM-l3z4Q&hl=no&sa=X&ei=IKZKUqrCCKXe4QSljYDIBw&ved=0CC8Q6AEwAA#v=onepage&q=Herb%20adams%20corvette%20%20IRS&f=false

all this drag racing stuff aint wasted on me you know.... ;) as for slapper bars, theres one near the 'shop.... love it.

Guys -- and this is just from my experience -- There is NOT that much force transmitted to the car through the swing/control arm -- What do you hear breaking first as the power goes up --

first it is the trans mounts, got to go to solid mounts and add a mid-mount,
second it is the axles,
third, it then the Ring and pinon and gears

When the Fiat was built, angle of and placement of the trans was the number one issue, and that car really hooked, with street tires no less.  And it wasn't until I got the turbo engine really humming (200+ HP), did I bend the stock fiat 600 swing arms that were designed for 21 HP

this is my understanding to of how it works not like a live axle

cheers andy

According to the theory you only have 25% of the forces to play with, so it's vastly more important what you do with it, as I see it personally.
The 25/75 split ties nicely inn with all the last posts... 75% is sucked up by the gearbox. No wonder it takes a beating.

I'm listening........intently!

How were you able to position the gearbox different to the usual Beetle setup to take advantage of the extra forces at play without breakage?
Slightly nose down? Angled so that on launch the box went parallel with the road surface? Just enough droop on the axles so that on launch they were dead-level with the road (and so CVs were also level, no angular power transmission)?

If it's a secret, I used to have a clearance.  :D

Think of the installation as using long ladder bars -- we just made sure that the torque was able to be transfered to the front of the car easily and we mounted the trans 1/2" to the left to keep the front wheels lifting at the same time rather than jerking the front left up first (the CG was set up 4" left of center with my big arse in the car, remember this was in my light weight Fiat) -- the IRS suspension was setup so it was flat and centered when the car was launched

because i have simply a lack of experience i can't comment much anymore. but i sure am learing some intresting things here.

Wheelies are always slow.

(http://scontent-b-iad.xx.fbcdn.net/hphotos-ash4/1381894_10151963294001223_231778716_n.jpg)

I had the same Car/Engine combo with a "stock" 4.12 Transmission and it would not Pull a wheelie.(180-200Hp) on Street Tires.
Had Gary Berg built a transmission with a 3.88 R&P and a 4.11 1st Gear, Added 6" M&H Slicks. Now I cant keep the thing on the Ground, Even with a Friend driving and the 2 Step turned All the way down ;D
but then I/We race for the Fans and Love Big Wheelies  ;)

Aloha's !
EBT Racing

i wound up the coilovers from the position they have been for the last few years and got my first big arsed wheelie  :D
60ft was shit though  ::)

Is that because you broke the beams with the back tyres though Danny? :D

My car used to squat the back and skim the front tyres on the ground but just the once it picked them up about 18" - never did it before or afterwards.

I was doing this but could not work out why my 60ft were not as I wanted. It was when I watched some slo mo's that it came to light.

I buy into this theory. It is the same as a swing arm on a bike.  I'm not great with calculations, but am a decent "eyeball engineer" and that seems logical to me.

I raced a GS 1100 streetbike in the late 90s/ early 00s, eventually working down into the high 7s at 180+ One of the biggest improvements I made was to raise the swing arm pivot 1", improving the swing arm angle, keeping it closer to horizontal and also putting the chain pull closer to the pivot. The suspension worked really well.

This is a similar concept minus the forces of the chain...

I have a 1" trans raise in my car. I sometimes wonder if this is counterproductive. It puts the plates in a downward slope  to the torsion housing. I have been raising the rear slowly to get the car to square the tire better at the hit. I think I am finally where I want to be. But I do not think it is optimal. I keep thinking about a torsion raise and stock height mounts. Raise up the torsion as much as I can get away with under  a stock package tray.

I'm good at creating work for myself.

My hero shot.

1.48 60 on muscle. The tires look pretty square to the track surface rather than decambered which is what I kept seeing in photos. A small change in axle angle made a big difference in rear camber at the hit.

Anthony

your ideas are pretty much correct going on what I have found in real life, the more I move the springplate upwards[ effectively lowering the car at rear] the more it squats and the worse traction their is, stock ride height seems to give really good traction
I understand why on swingaxle cars people use the 1inch trans raise but in reality I am not convinced it really helps. A 2-3 inch torsion raise would be really effective but it does take it along way from a regular street car 

cheers Richie

When I played with small sedans it was always difficult to get traction off the mark AND get the car low enough to help stability at the top end, small light cars get blown around a lot more than a 360 Valiant, as I'm sure you all know well!  :D

I ended up changing tyre size to help. I have since always used a 23.5 x 8" or a 24.5 x 8" tyre on a 13" rim. It has the same sidewall height, and therefore "bite" as a normal 26 x 8" on a 15" rim, but lowers the back a good inch on it's own. My best 60ft using the McCreary 23.5" was 1.52, but that was with the hard compound that lasted for better than 50 passes, the medium and soft would hook harder I reckon.

One more option to consider to get the back down a bit for you guys maybe?

with swing axle, as the front comes up, so the rear wheel load de creases because the trailing arms are going nearer vertical, this is also allowing the rear toe to increase because the rear is increasing its positive camber which becomes toe in all on its own as the geometry rotates, all because the applied load is diminishing, irrespective of the drive shaft/engine torque applied to it, basically its becoming a Ballet dancer up on points, not good and easy to push over,,,keep 'em  down nice and low, but its another plus point for IRS with its reduced camber change.