Home Made Splitters/undertrays

[zebra]

In the coming weeks I aim to embark on making an undertray for my R33.

Thinking about making it out of 3-ply with a fiberglass overlay.

But what I would like to see is how people have mounted theirs under the car and if you have made any channels in it for super mega downforce.

Cheers

Andrew

[Dale FZ1]

Composite signboard, approx. 4.5mm thick and reasonably flex free. Runs back to the steering rack.

No fancy channels. No splitter section as yet. I consider it is simple design.

Was a bit fiddly to get the whole thing in place. Time permitting I will put some pics up on my R33 build thread.

[Duncan]

will it have to meet any CAMS regs? Prod cars, IPRA and Sports Sedans all have very specific rules about allowable sizes

BTW James has what seems to be a good one on his car, seemed to be a bit fiddly to put on but is working well

[zebra]

I've got an aftermarket front bar, which incorporates a bit of a splitter, so was going to match it up to the undertray.

Pic for reference

[zebra]

will it have to meet any CAMS regs? Prod cars, IPRA and Sports Sedans all have very specific rules about allowable sizes

BTW James has what seems to be a good one on his car, seemed to be a bit fiddly to put on but is working well

Nah,

Just track days and the odd hill climb

If it means running SV than I'll run SV

[fatz]

old mate who made mine can make them hang a foot or two out the front and sides like the time attack cars if ya want

was about 750 installed

[Tonba]

^ That's quite a neat setup. Too bad it doesn't go back much further though.

[zebra]

Very neat. Too fancy for a gtst though haha

Who made it for you pete?

[89CAL]

That looks great.

I've always thought about making an under tray for my car but always get to slack just starting to think about all the complications lol

[fatz]

Very neat. Too fancy for a gtst though haha

Who made it for you pete?

custom carbon

[SimonR32]

Anyone think they actually get reasonable gains from them?

I've got a AB flug carbon one at home which I've been waiting to fit, will be interesting to see if it does anything... Otherwise it's a nice rice mod

[MBS206]

James (GrumbleBee) said he found a noticeable gain in front end grip when he fitted his. I'd say designed properly there are definite gains to be had. Designed poorly, well, you could end up with less downforce!

[Russman]

Simple setup I ran for a couple of years.
I like ally as it's easy to work with even though it's not the lightest. Very noticeable gains at PI and EC through long fast sweeping corners even though it was just flat underneath.

[gtr jet]

Would it make the car unbalanced at all having a front splitter with a factory rear wing?

[GTR-N1]

At speed...

1) If front splitter and connecting undertray are flat with negligible air disturbance > negative pressure under front of the car > front 'sticks' to the tarmac.

2) If the rear wing is set up to create downforce > rear 'sticks' to the tarmac.

1) + 2) > all's good

[gtr jet]

At speed...

1) If front splitter and connecting undertray are flat with negligible air disturbance > negative pressure under front of the car > front 'sticks' to the tarmac.

2) If the rear wing is set up to create downforce > rear 'sticks' to the tarmac.

1) + 2) > all's good

What if one works a lot better than the other?

[zebra]

Can never have too much front end grip imo

[Dale FZ1]

The sort of front end device we're talking about won't really produce downforce to the extent that aero loading increases the effective vehicle weight above static.

An effective splitter design should protrude a fair bit, and its height above the ground has a big bearing on efficiency/effectiveness.

The outcome I found with my undertray (no splitter) is noticeable reduction in high speed understeer, less tendency to run wide through high speed sweepers. More front grip at speed is good .

[gtr jet]

The sort of front end device we're talking about won't really produce downforce to the extent that aero loading increases the effective vehicle weight above static.

An effective splitter design should protrude a fair bit, and its height above the ground has a big bearing on efficiency/effectiveness.

The outcome I found with my undertray (no splitter) is noticeable reduction in high speed understeer, less tendency to run wide through high speed sweepers. More front grip at speed is good .

That's exactly what I wanted to hear.

I don't even have the factory undertray atm and my car is horrible at taking high speed corners.

[Trex]

HT have a few home made splitters in the build section