Mythbusters.

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Mythbusters.

Post by Sinbad » Tue Mar 08, 2011 5:41 am

Fix the suspension. Downforce won't help you there. It will just slow you down.
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Re: Mythbusters.

Post by Abnormal » Tue Mar 08, 2011 7:46 am

Sinbad wrote:Fix the suspension. Downforce won't help you there. It will just slow you down.
+1
my understanding is that these wings can only create down force at serious speeds. Not sure how beneficial that would be on a drag car.
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Re: Mythbusters.

Post by Jetta2 » Tue Mar 08, 2011 2:53 pm

Wit Ark wrote:Refering back to the roof spoiler on the back of a citigolf, what about a wing? I take it this will have a negative effect on top speed.... I am now not refering to those massive japanese wings they use on drift cars or show and shine competitions, just a smallish wing. Is there really any downforce being created when going faster with something as such or just pure drag?

I want a bit more grip on the back of my citigolf dragster as the end really gets loose when going faster than 140km/h, ok granted the suspension are farked and these needs to be looked at first, but back to the innitial poin, will a small wing be worthwhile for lets say faster speed stability/handling and at what speed/drag compromise?
Putting a wing on the back of a Citi will make the rear heavier when downforce starts acting on the car at whatever speed it becomes effective, thereby actually making the front of the car lighter and in so doing, making steering all farked up and reducing grip to the front wheels.

Fix the suspension first with quality parts, then work from there. Adding a wing will do nothing for the aerodynamics of the Citi bodyshape anyhow IMHO.
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Re: Mythbusters.

Post by Scatman » Wed Mar 09, 2011 9:59 am

The citi/mk1 has an exceptional drag coefficient :twisted:

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Now this is cool:

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These are the areas to work on to reduce drag:

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This lets the Vtak guys keep the car on the road for when the Vtak kicks in Yo :lol:

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Re: Mythbusters.

Post by Shizzo » Mon Apr 04, 2011 7:53 am

Jetta2 wrote: Putting a wing on the back of a Citi will make the rear heavier when downforce starts acting on the car at whatever speed it becomes effective, thereby actually making the front of the car lighter and in so doing, making steering all farked up and reducing grip to the front wheels.
No, it will not make the front lighter. There is no pivot in the middle of the car that would cause that to happen.
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Mythbusters.

Post by Sinbad » Mon Apr 04, 2011 7:55 am

If the wing is behind the rear axle, there is your pivot. But given the lever lengths involved it's likely to be negligible.
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Re: Mythbusters.

Post by Wit Ark » Tue Apr 05, 2011 1:54 am

I heard by adding a roof spoiler on a mk1 up to 4km/h faster top end can be acchieved as this apparently does *something to reduce drag, looking at the pick posted with the yellow golf, i cannot see how a spoiler on a mk1 can lessen drag, in fact it will make it worse. Shall we put this myth to the test???
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Re: Mythbusters.

Post by Citi 007 » Tue Apr 05, 2011 7:05 am

Wit Ark wrote:I heard by adding a roof spoiler on a mk1 up to 4km/h faster top end can be acchieved as this apparently does *something to reduce drag, looking at the pick posted with the yellow golf, i cannot see how a spoiler on a mk1 can lessen drag, in fact it will make it worse. Shall we put this myth to the test???
you mean the OEM CTI bootspoiler right?
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Re: Mythbusters.

Post by Wit Ark » Fri Apr 08, 2011 8:38 pm

Jip, thats the one, well not nesecarily the OEM one, any one for that sake? Plausable????
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Re: Mythbusters.

Post by Zubair » Fri May 27, 2011 10:46 am

You donot even want the std OEM CTI Kamei roof spoiler on a drag Golf. It won't do anything but create downforce on the rear which is what you don't want on a drag car.
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Re: Mythbusters.

Post by Scatman » Sun May 29, 2011 3:05 pm

Zubair wrote:You donot even want the std OEM CTI Kamei roof spoiler on a drag Golf. It won't do anything but create downforce on the rear which is what you don't want on a drag car.
Why not? Shouldn't the rear of the car be stable at high speeds? I can't see that a Kamei spoiler would even make 0.01sec difference because of added drag?
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Re: Mythbusters.

Post by sean919 » Tue May 31, 2011 6:04 am

I think its plausible (that it can increase the top speed of a car). Being that aerodynamic drag is pretty much the only thing limiting top speed, changing the aerodynamic impact of the car will have an effect, to some degree, on the car's drag coefficient. Have a look at Scatman's post below - the Kamei spoiler will have a similar effect to the bottom left diagram. So it will have an effect on the Cd and hence top speed, but then again will most likely be marginal...


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Re: Mythbusters.

Post by Peddersgolf » Fri Jun 10, 2011 8:22 am

Haha, this thread is ace.
I watch Mythbusters always and some of the things as regards the citi is good discussion.
Good to see if ideas actually work, does anyone actually test these ideas to see if they are confirmed or plausible
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Re: Mythbusters.

Post by slakkie » Fri Jun 24, 2011 1:29 am

BlueBlob wrote:Here's 4 more:

7) Big intercoolers or long boost pipes give more lag. Crap.
8) the whole 8V makes more torque than 16V thing. Crap.
9) You can raise the octane of your fuel significantly by adding 7ml of some liquid. Crap.
10) Boost puts more strain on engines. Crap.


edit: Nice thread, by the way.
I agree on point 8... See this post... http://www.enginesforsale.co.za/?p=49
And look at the dyno sheet.
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Re: Mythbusters.

Post by N/A power » Wed Jun 29, 2011 5:09 pm

thumbs up
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Re: Mythbusters.

Post by SemiColon » Thu Aug 04, 2011 2:15 pm

Newest Myth:

6R Polo GTI is faster than a 9N3 Polo GTI.....lol
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Re: Mythbusters.

Post by Abnormal » Thu Aug 04, 2011 3:10 pm

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Re: Mythbusters.

Post by SemiColon » Thu Aug 04, 2011 3:17 pm

Nerville wrote:6R 0-100 6.9s top speed 229
9N 0-100 8.2s top speed 216

http://www.um.co.za/specifications/volk ... 08%29.aspx
http://www.um.co.za/specifications/volk ... 11%29.aspx
You see, Myth...
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Re: Mythbusters.

Post by CC-SA » Sat Aug 06, 2011 12:10 pm

The 2006 9N3 Polo GTI I had was stock standard except for that I drilled allot of 10mm holes into the bottom section of the airbox and also removed the flap at the air intake behind the grill. I also replaced the OEM Continentals tyres with Nankangs. I floored the GTI in 5th gear while driving on the N4 highway towards Pretoria, the GTI reached 6500rpm which is also the rev limit point on stock engines, the Speedo was at roughly 245km/h(I reset the average speed on the trip computer and it showed 230km/h :eek: - roughly true speed). Previously with the stock tyres and airbox the GTI ran out of oomph at 225km/h(Speedo) :sad: .

According to the CAR Magazine review of the Polo GTI, the calculations of the gear ratios showed a top speed of 232km/h at 6500rpm.

The GTI did feel quicker with the drilled airbox but I newer tested the 0-100km/h time.

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Re: Mythbusters.

Post by Velofox » Fri Aug 19, 2011 10:50 am

does a leaking exhaust effects fuel consumption?
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Re: Mythbusters.

Post by Scatman » Fri Aug 19, 2011 9:04 pm

Velofox wrote:does a leaking exhaust effects fuel consumption?
I would say YES on that one... When my exhaust had a crack where the two pipes bolt onto the branch, my fuel consumption spiked to 10km/l, instead of the usual 12-13km/l... I say it's plausible. But I have to add that it will become less apparent the further away the leak is from the branch, i.e. a leak at the branch would have a bigger impact on fuel consumption than a leak near the end of the echaust system...
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Re: Mythbusters.

Post by 1.8iblackie » Fri Sep 30, 2011 8:25 pm

Scatman wrote:
Velofox wrote:does a leaking exhaust effects fuel consumption?
I would say YES on that one... When my exhaust had a crack where the two pipes bolt onto the branch, my fuel consumption spiked to 10km/l, instead of the usual 12-13km/l... I say it's plausible. But I have to add that it will become less apparent the further away the leak is from the branch, i.e. a leak at the branch would have a bigger impact on fuel consumption than a leak near the end of the echaust system...


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Re: Mythbusters.

Post by marzbars » Mon Oct 03, 2011 1:18 pm

Here is an office myth that needs busting
A towbar protects yur car during a rear-end smash.
I say BS as it will cause structural damage to the chassis on a bigger impact
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Re: Mythbusters.

Post by Uncle Nunda » Mon Oct 03, 2011 1:22 pm

marzbars wrote:Here is an office myth that needs busting
A towbar protects yur car during a rear-end smash.
I say BS as it will cause structural damage to the chassis on a bigger impact
i think this is better suited to a bakkie
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Re: Mythbusters.

Post by Scatman » Mon Oct 03, 2011 2:27 pm

The way towbars are fitted on most compact cars today makes this plausible, I'd say that the towbar will save you from damage in a slight bumper-bash, but if someone knocks you at around 30-40km/h it will probably do more damage than without the towbar. With a towbar, you'll probably save yourself from cosmetic damage on your car, but I agree with you on the point that it will do more damage to your car at slightly higher speeds...
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