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buildabiggerboxer wrote:you have to be a registered fun cup team to buy any parts, but no need to buy a workmate to bolt on the back anyway, the best aero performance is free and nobody uses it, its called ground effect and it will work for you at 40mm ground to pan clearance, no cost, no weight, no drag, no kidding.

Thats not true you can buy the parts here
http://orders.funcup.co.uk/categories/Fun-Cup-Parts

I initially was going to buy the front spoiler, but changed my mind because I realized it was going to be more work than expected.

richie,uk wrote:

pickstock wrote:I used to think most wings were a waste of time
Until we towed a Nissan rally car in reverse, the trailer wiggled all over the place

That is usually caused by having the weight at the wrong place on the trailer more than an aero issue

yes but it was the weight change a the front caused by lift on the wing.

buildabiggerboxer wrote:you have to be a registered fun cup team to buy any parts, but no need to buy a workmate to bolt on the back anyway, the best aero performance is free and nobody uses it, its called ground effect and it will work for you at 40mm ground to pan clearance, no cost, no weight, no drag, no kidding.

i wouldnt be to sure about that at 40mm, i know that 4.5mm is a lot better, as for no weight well the tunnels that you need to make aren't flat so there is added weight (look at the Ferrari F40)

And no cost? so your saying Ferrari or any of the WTAC teams wasted 150 grand doing tunnels for ground clearance?.....

sorry dude but really there is a lot more to it all than most people understand (I dont pretend to understand it all, but i know there's a lot more to it working then pretending)

buildabiggerboxer wrote:you have to be a registered fun cup team to buy any parts, but no need to buy a workmate to bolt on the back anyway, the best aero performance is free and nobody uses it, its called ground effect and it will work for you at 40mm ground to pan clearance, no cost, no weight, no drag, no kidding.

i wouldnt be to sure about that at 40mm, i know that 4.5mm is a lot better, as for no weight well the tunnels that you need to make aren't flat so there is added weight (look at the Ferrari F40)

And no cost? so your saying Ferrari or any of the WTAC teams wasted 150 grand doing tunnels for ground clearance?.....


No, ive not said any thing like that, you are saying it, 4.5 mm is for race cars, not street bugs, i am only talking VW and keeping to the regulations i have to run to, tho its full race, my car also runs on the street, again for regulation purposes..

Yodogg, yes, 1.6 inches, this is a very good practical setting and tests on the watch to half a second per mile over a 55mm ride height, and its streetable o.k if set up right with drop spindles, i drive mine on the street, but like any extreme set up, it requires work, jack points etc need to go, and the lower front shock tower ground flat to the tube, as you know, mine runs flipped a arms for under tray and venturi clearance, so the shocks are re located without the stock lower mountings in the way of things, the floor pans are also raised slightly behind the seat area, just enough to keep the techie inspectors happy, but you dont have to go that far, Ive worked hard on raising the trans and engine to gain ground clearance as we bash the kerbs very very hard, the exhaust also is relocated for the same reason.

Do you have any figures to follow it?

just saying it works when it goes against all testing means nothing. We limit most classes to 40mm to prevent the use of ground effects.

pickstock wrote: Do you have any figures to follow it?

Yes, read above again.

just saying it works when it goes against all testing means nothing. We limit most classes to 40mm to prevent the use of ground effects.

perhaps you read it and forgot quickly.

but if you read my post again you will see the gain in lap time with different ride height. the watch cant lie, with further work now done, i'm now pulling a full 1.2 seconds per mile with just underbody work and playing with rake angle, some gain is from a lower centre of mass admittedly , but its well known a clean underbody outperforms a big wing with added drag and a raised c/g, i run a raised exhaust system and relocated shocks just to clean up the underside and allow the underpanels to fit, this means a dry sump oil system as the sump is not in the air stream anymore, nothing is an easy gain,i put in the work, do you? but dont take my word for it that underbody airflow works , check out the Lemons blitzwagen post from fjc with side skirts and front air dam.

buildabiggerboxer wrote:

pickstock wrote: Do you have any figures to follow it?

Yes, read above again.

just saying it works when it goes against all testing means nothing. We limit most classes to 40mm to prevent the use of ground effects.

perhaps you read it and forgot quickly.

but if you read my post again you will see the gain in lap time with different ride height. the watch cant lie, with further work now done, i'm now pulling a full 1.2 seconds per mile with just underbody work and playing with rake angle, some gain is from a lower centre of mass admittedly , but its well known a clean underbody outperforms a big wing with added drag and a raised c/g, i run a raised exhaust system and relocated shocks just to clean up the underside and allow the underpanels to fit, this means a dry sump oil system as the sump is not in the air stream anymore, nothing is an easy gain,i put in the work, do you? but dont take my word for it that underbody airflow works , check out the Lemons blitzwagen post from fjc with side skirts and front air dam.

Figures...

Figures that say i went faster in a non controlled environment mean nothing to anyone.

1.2 seconds per mile sure, but to me that means nothing. What style competition drags? what was the weather like, temperature, traction, driver.
There is nothing scientific about your ideas, im talking wind tunnel testing or CFD.

Just found this video online, really short and without much info, but seems like the creator use Solid Works to simulate a Bug in a wind tunnel. Maybe someone smarter than me can explain what it means and if it's a good simulation, haha.

https://youtu.be/LtXOUrTc_dA

Very interesting!

I didn't expect the flow over the top so far back on the rear deck nor the dramatic curl behind the car. It does explain the more or less dead spot by the rear hood. The flow on the side is also farther out than I would have suspected.

Happy that you posted the airflow diagram.

Lee

We have spent a lot of time on aero over the December holidays. It looks like a race car now... however, according to the data logger there is no difference in corner speeds and the car's straight line speed is down from 100mph upwards. Up to 100mph the acceleration is identical.

We did test with and without the rear diffuser. I could feel a difference with the diffuser on / off. It generated too much rear grip and the splitter not enough, which meant that it would push the nose through the high speed sweeps. The other issue with the diffuser was the engine bay temperatures due to the engine not being able to get rid of hot air as efficiently.
This has started to make me think that maybe the beetle's natural aero is not that bad after all... we will test again this weekend, but without aero to make sure that the straight line speeds are back to normal and its not a hp issue.

It looks really cool. Bonneville would been a fun place to play with all your mods.

4agedub, when you talk of the "defuser" are you talking about the "splitter" under the bumper? The underside of the VW is to flat to start with but then the top of the body is roughly shaped of the upper lifting surface which kind of gives the illusion of the lifting surface of a wing. Never thought of this before... hmmm.

A very nice clean lined toy if you don't mind me saying so.

Lee

The front splitter runs up to the pedal box, the rear diffuser sits underneith the engine and is mounted to just in front of the transmission.

What 'formula' did you use 4agedub to build the diffuser?

Any ideas on creating more down force at the front end? Dive planes perhaps?

I see the front fenders are vented but not the rears?

I noticed a big difference on my car venting the fenders.