Rear Spoilers.... Necessary?

[tacker]

I have a track only R32 GTR and i can tell you it does make a difference. I have an APR adjustable wing and it can either be a help or a hinderence it does take time to get the set up right but it will be a benefit if you take the time to set it up.

I did a test with my engine builder who reckons there crap and do nothing, 2 laps at full angle seen him bouncing down the straights ( very funny ) 2 laps at no angle saw his over steering at every corner again very funny! and 2 laps at normal settings... i believe he now likes rear wings!

[Sydneykid]

A few random thoughts;

The front undertray helps a lot with the cooling, I wouldn't leave them off for that reason alone. They increase the airflow though the intercooler and radiator by creating a partial vacuum under the engine bay. When we ran the R32GTR in Production Car racing it would overheat without the undertray.

"Add downforce" is a bit of a misrepresentation, more like "decrease the lift". Without the front undertray we were getting more lift at the front at anything over 100kph, I could see it on the shock sensors data log. The dogleg at Oran Park was a prime example, the air would get under the front and lift it up, put the undertray back on and that lift stopped.

After spending 2 seasons with the F3 and half a day with Frank Dernie (ex Williams, recently Toyota) I can positively say I don't know anywhere near enough about aerodynamics. But what I am confident in is that modifying the front standard undertray to fit an aftermarket front bar, with say aluminium extrensions, would not be a bad thing.

Cheers

Gary

[9krpm]

Thanks for the info Sydneykid.

What undertray have you got in the R32gtr?

[Sydneykid]

Thanks for the info Sydneykid.

What undertray have you got in the R32gtr?

It's a Production Car so the standard undertray is it.

The R32GTST is built to the Improved Production regs so it has a flat undertray with a splitter out the front to the profile of the bumper. The regs only allow the undertray back to the front of the wheel arches.

If I had full freedom, I would simply copy a V8Supercar undertray which has a raised centre with votex generators.

Cheers

Gary

[SS8_Gohan]

thanks for the Gary and others...

under body aero was what i was really keen on as well. I thought it might be more beneficial than putting a spoiler on it...

unfortunately with my front bumper, i had to take the middle factory undertray off as it had to where to attach to the East Bear front bumper...

But when i was looking at it, from the side, it looks like this...

|

|

|

|

|_____________ (front of car here)

And because the front edge had nothing secure to attach to (besides my bush mechanics)... it did this at high speeds...

|

|

|

|__

.....__

.........__

.............__

.................__ (ROAD contact followed by horrible noise)

And it just seemed like all it would do was act as like a parachute at the front?

As in, wouldn't it just create more drag when the air slams into the upright section??

If i were to get a full undertray, or just to the front of the front wheels, it wouldn't matter then if i didn't have the factory undertray?

Does it matter what a full body undertray is made out of??

someone want to lend me some money for these CF parts? i'll put your like workshop sticker on my car or something

i swear they had a front one too, but i can't find it....

R35 GTR

[Rekin]

Sorry to hijack, but can anyone shed some light if the electronic front spoiler on most r32 gtst's do anything?

It pops out at 80km/h and was wondering if it actually helps?

My car also came with a c-west gt wing when first bought it, the rear of the car felt really unstable on the freeways haha, pulled if off and drives much better It was set on max angle and never bothered to play around with it

[SS8_Gohan]

is that factory?? shit i've been around here for a while and had NO IDEA 32's had that

[Rekin]

is that factory?? shit i've been around here for a while and had NO IDEA 32's had that

haha yeah its factory but i think it was an option as not all r32's have it.

[Boss-zilla]

Its on the type 'm' and gts-4's, i just pulled mine off, weights a hell of a lot.

[Sydneykid]

thanks for the Gary and others...

under body aero was what i was really keen on as well. I thought it might be more beneficial than putting a spoiler on it...

unfortunately with my front bumper, i had to take the middle factory undertray off as it had to where to attach to the East Bear front bumper...

But when i was looking at it, from the side, it looks like this...

|

|

|

|

|_____________ (front of car here)

And because the front edge had nothing secure to attach to (besides my bush mechanics)... it did this at high speeds...

|

|

|

|__

.....__

.........__

.............__

.................__ (ROAD contact followed by horrible noise)

And it just seemed like all it would do was act as like a parachute at the front?

As in, wouldn't it just create more drag when the air slams into the upright section??

If i were to get a full undertray, or just to the front of the front wheels, it wouldn't matter then if i didn't have the factory undertray?

Does it matter what a full body undertray is made out of??

A properly designed front undertray helps hold the front lip up off the ground. The idea of a front splitter/spoiler is to make the air go either over or around and NOT under.

The problem with underbody aero is that it depends on proximaty to the ground (that's why it's called "ground effect"). On a production style car (in comparison to a formula car) that's very difficult to achieve. A simple example, when you brake the rear goes up and loses the ground effect, hence you get trailing brake oversteer. Conversely when you accelerate the nose lifts, you lose front end ground effect and corner exit understeer can result. Don't think that you can fix this with exagerated spring rates either, a production chassis simply isn't rigid enough, production tyres have flex in the sidewalls and you lose so much mechanical grip (from the high spring rates) that the aero doesn't compensate.

That's why race cars have wings, sure they have some underbody tidying up, but the front spoiler and rear wing do more than 80% of the work from an aerodynamic viewpoint.

If they are available, carbon fibre is the go, whereas custom undertrays are often made out of aluminium sheet, 2 mm, 2.5 mm and 3 mm are common thicknesses depending on the size and load.

Cheers

Gary

[Angus Smart]

I've been thinking about a new under tray for the front as mine was butchered in japan

Japanese: http://www.silkroad-jp.com/section/dif.html

translated: http://translate.google.com.au/translate?u...en&ie=UTF-8

Silkroad seem to make a nice unit.

and looking at top secret rear diffuser also. but i think they are more looking nice than anything.