Spoiler removal - reasons?

[Anders_R35]

Originally Posted by Marky_GTSt

Correct, They actually chose that particular level of down force, If you want to improve it, lower the car.

I think the down force generating wings would benefit cars that are tracked often where grip and handling comes before economy. But the original question was about removal of the spoiler for drag racing, And I suspect we have put forward a strong case for leaving it on for more or less all purposes.

Agreed, now John Hanton and SVM team need to do a run with spoiler on to see how it effects their record

[Marky_GTSt]

Originally Posted by Anders_R35

Agreed, now John Hanton and SVM team need to do a run with spoiler on to see how it effects their record

Honestly, all things considered, I doubt it will change anything that can be measured on a strip. Flying mile or top speed runs possibly, but I can't imagine a way to accurately measure it.

[Kev@SVM]

Hi, we have tried back to back many times !
Spoiler off = 2-3mph higher in top speed. (on a qrt) myth busted ,sorry lads

Can't say to much tonight, but i can confirm we have just taken a spoiler off today,
just to gain such an improvement,car will be racing this weekend i will let you all know how he gets on !

However for stablity on top speed runs we intend to keep it on, as above 200mph car moves around to much we just will increase power , asking both f.man and JH both did the fastest times @totb they agree
We are taking Hulk to a wind tunnel to see what happens above say 160mph as our target speed is now 240mph what is best and what height to set ?
Most guys set their car high, so the air goes under,this unsettle's the car,but you can fudge a higher top speed with balls of steel lol
kk

[Marky_GTSt]

Originally Posted by Kev@SVM

We are taking Hulk to a wind tunnel to see what happens above say 160mph as our target speed is now 240mph what is best and what height to set ?
Most guys set their car high, so the air goes under,this unsettle's the car,but you can fudge a higher top speed with balls of steel lol
kk

I would be very interested to see the results of this...

As for the small increase in speed without the spoiler, I have to wonder what might be happening there, An interesting observation indeed but I don't think you can quite call it busted yet. When you saw the extra2 to 3 mph, what speed where you going ? I wonder if the spoiler becomes detrimental above a certain speed ? what other mods did you make ?

I think you need to do it with a stock car to really tell tbh.

[Kev@SVM]

ok will try more on?off tests
Maybe the cars will go even faster Lol for now we will keep chipping away at going faster and faster,We will keep testing all ideas, thanks for all views, we will maybe come back to this . i must agree car looks better with it on, as Nissan intended
kk

[Marky_GTSt]

Originally Posted by Kev@SVM

ok will try more on?off tests
Maybe the cars will go even faster Lol for now we will keep chipping away at going faster and faster,We will keep testing all ideas, thanks for all views, we will maybe come back to this . i must agree car looks better with it on, as Nissan intended
kk

It sure doesn't hurt to gather more data, I'm forced to wonder why it still works as a stabiliser at high speed but apparently has detrimental effect on the quarter, My suspicion is there is more at work here than just the spoiler.

Im beginning to suspect that it may be tuned to work in a certain speed range of the stock car and may indeed be less than perfect at higher speeds, but the stabilising effect at those same speeds has me puzzled???? Maybe they really did sacrafice a tiny bit of drag for greater stability, but it sure doesn't look like they did in that document.

Either way, fascinating stuff.

[Tigerruss]

Not sure Kev's talking of the stock spoiler?

[Marky_GTSt]

Originally Posted by Tigerruss

Not sure Kev's talking of the stock spoiler?

Ah, that might explain things if true, We where discussing stock ones only, Any other kind will most likely produce more drag and give the results Kev provided. It also raises an interesting question, will said car go faster with a stock spoiler back on ???

[MattGTR750]

Amazing stuff thank you so much everyone - I've learnt a lot today!

Kev, what do you do about the boot lid when you remove the rear spoiler as it looks terrible?!?

So for 1/4 mile stuff and 30-130 days I will not be running a spoiler

[Marky_GTSt]

Originally Posted by MattGTR750

Amazing stuff thank you so much everyone - I've learnt a lot today!

Kev, what do you do about the boot lid when you remove the rear spoiler as it looks terrible?!?

So for 1/4 mile stuff and 30-130 days I will not be running a spoiler

Just hang on before making a conclusion, as it's possible Kev was running an aftermarket wing, So his results may not help in deciding how well the stock spoiler works.

[Kev@SVM]

Originally Posted by MattGTR750

Amazing stuff thank you so much everyone - I've learnt a lot today!

Kev, what do you do about the boot lid when you remove the rear spoiler as it looks terrible?!?

So for 1/4 mile stuff and 30-130 days I will not be running a spoiler

Unfortunately, a new carbon, boot lid , or repair and paint, You have to be very keen though as to such a small gain,

Regarding, what type we have swapped?, Both! oem and modified "All" seem to have had gains on removal in a straight line pull, and Yes the larger fin types even more gain

As said though there are theories for both, so a trip to Mira (wind tunnel) will give us factual data,instead the "we won "so its right approach
Maybe,making a U turn , Refitting and will give us a little extra pace?

I will let you guys know, ON or OFF result kk

[Kev@SVM]

EG of Results,,

Marham 2012,,,Hulk No spoiler 218mph
Stevie G...Spoiler 204mph
chubbie....big spoiler..187 mph
All top speeds were calculated on a 1.1 mile Run...Ok mine was the most powerful,lol but
stevie g and chubbie were approx the same power !

Another example,
Two 650Rs...Taken to Crail, with spoiler on, dropped 5mph (same cars)

Everything is worth a shot in competition imo , that extra, maybe all it takes

As said though, I will listen to all views, and have another Go
Back soon![B]
kk

[Marky_GTSt]

To really compare you need to use the same car each time, Ideally under the exact same conditions, The Wind tunnel will be the best approach and if possible compare the Hulk to a stock GTR and see if there are other factors involved, Its possible the modifications made both externally and in the engine bay may play a part in this...

Look forward to some results.

[Anders_R35]

The slight probem with Mira is maximum wind speed of circa 80mph, I suppose most manufacturers are happy with that with national speed limits in most countries not exceeding this. They make calculations for results above this speed, but who knows what vortices and additional turbulance happens at 180mph?

I had planned a trip to Mira post fitting Litchfields front lip and the ARP rear spoiler to see what additional downforce was created / lost and how it effected the balance of the car. I'll need to invite another MY11 in stock Aero trim as a comparison, was going to invite Adam.

[rasored]

Originally Posted by David.Yu

Good point Mark. You'd be hard pushed to improve on a Cd of 0.27 and the GT-R does not produce a great deal of downforce, so not sure what benefit there is to removing the wing.

And as Matt says, the holes left behind look tatty and I think the car looks unbalanced without the wing.

Of course I've probably completely screwed the aero with my carbon raised wing...

Nissan claims the GT-R generates more than 176 pounds of downforce at 186 mph. FRONT AND REAR . According to wind-tunnel tests by the German magazine Sport Auto, few production cars are better, and those few—the Bugatti Veyron, the Mercedes SLR McLaren, and the Porsche Carrera GT - downforce will start at about 45mph

Remove the rear spoiler - and over 60mph you will notice the difference !

Took the spoiler of my old BNR32 and all it did was go sideways .........