DIY FRONT SPLITTER

[BlackKnight1982]

Ive finally finished my front splitter today.
Here are a few pics of the process.
The splitter started life as a 6mm thick piece of marine plywood (waterproof)
While lifting the front end of the car into the air i used stands to hold up the plywood to the car then i carefully drawed the splitter shape out.
Then i cut it out using a jigsaw, once half way through i used the piece i had just cut off as a template to get a matching curve.

Once cut out it was carefully sanded down and several coats of black floor paint which is highly durable and waterproof was added to each side, i gave mine 4 coats but its down to you really.
Once all the paint was dry & hardened i used 6mm black edge trim which i carefully pushed onto the leading edge of the splitter.
I used 4 black pan head screws to hold it in place, tbh it doesn't really need them but i would rather be safe then sorry.

I used two existing holes in the radiator/condenser bottom support bracket. For which i put 10mm head 50mm length bolts through with the relevent washers & put a nut on and tighting it up onto the bracket then i used 10mm ID oil/fuel hose which i cut down the make rubber spacers to go over the length of thread & existing nut which i had just tightend up.
I put the splitter up to this and marked the splitter where the thread of the bolts touched then drilled the 2 holes.
I then bolted on my two front spitter support rods which would hold the front of the splitter. I bolted these through existing holes which the lower bumper rubber fixes on.

Once this were fixed to the bumper i placed the swivel head end were i wanted it and marked and drilled two holes.
I then bolted the splitter using nylock bolts & big washers to the 2 rear mounts which have the rubber hose on & to the front bolts which go through the support rod.
I also fitted two speed screws with speed clips & washers, on either end of the splitter through onto the tabs on the bottom of the corner vents of the bumper.

FINALLY FITTED

Ive got about 80mm of ground clearance on the front but mine is lowered 55mm all round, ive taken it out today and it seems to have a made quite a difference to way it handles, alot more than i anticipated.

 

[chris3boro]

Liking it, love the matt black look, stealthy!!

 

[red]

A for effort, good work

Just remember not to go too fast through those deep puddles now!

 

[e3silversurfer]

what material is the splitter made of? plywood??

 

[Dal]

3rd line of his post Elvin - Marine Plywood.

 

[e3silversurfer]

cant believe it is plywood

 

[BlackKnight1982]

Yep its marine plywood!
Loads of people on the racing scene use plywood splitters as they are extremely light, hard wearing, cheap to replace if broken or damaged which you can guarantee you will at some point, opposed to carbon fibre which just explodes if you were to hit a fly!!! lol

 

[BOK]

You're quite brave attaching it with just 4 bolts...have you conducted any high speed tests with it yet? Hold your hand out of a open window at 80MPH to get an idea of the forces involved.

My experience with splitters breaking at high speed potentially damages the bumper and lower front grille.

The rule is, if you can stand on the splitter without it breaking off you should be OK at high speed.

 

[spike.]

looks fanstastic!

not sure if i;d stand on my spitter. I would agree with colin, add a few more bolts, tho!

 

[BlackKnight1982]

There is actually 6 fixings holding it on, the washers ive used are fairly large to spread the load. I know how the air feels at higher speeds than 80mph i also have had motorbikes i the past. yummy
I can stand it, i took it upto 120mph today and it seems fine.
What experiences have you had with splitters breaking?

 

[BOK]

What experiences have you had with splitters breaking?

Twice when air got between the splitter and bumper, the splitter set up a resonance which shook the whole car, followed by a bang and bits of plastic everywhere. I was into three figure speeds for this to happen...

Problem solved with reinforcement and a modification to the front panel!

Luckily the bumper was not damaged but the lower grille snapped off as it forms part of the structural rigidity of the lower bumper.

You have to be so careful with a lowered car with a splitter- parking towards a kerb and doing a U turn, which is how mine managed to pick up a scrape. Oh and sharp inclines/ramps into car parks, tall speed humps etc...

 

[BlackKnight1982]

What reinforcement modification did you do? Im interested as i may do it to be sure if you have had probelms before!

 

[BOK]

Very strong aluminium brackets, a solid piece of plastic bolted in as a filler panel between bumper and splitter (was actually made from the remains of the old splitter!) a skim of sealant between the bumper and splitter (no chance air will get in between) and two threaded steel supports sheathed in heat shrink bolted perpendicular to the splitter/bumper.

I've hit several things with the splitter since, hasn't budged

 

[jacko]

sweet!

even my ford motorsport carbon splitter is only 1mm ish of carbon with plywood underneath! (iv known a few people remove the plywood & it flaps all over the place). the carbon is basically there to look pretty....
(might re-do the plywood bit on mine soon (it isnt treated!) and add a lower carbon layer to sandwhich it & keep the water off)

frp uses 3 fixings per side, 2 behind the grill very much like bok has done in front of the grill, and the centre one to hold the grill in (very much doubt thats structural tho)

i like it, nice one


ps; the manual for the frp from tickford states not to drive through deep floods at more than 10mph.

 

[BlackKnight1982]

Nice guys, this information is greatly appreciated. I took the puma out for a run down the lanes today ive caught the bolts on the underneath side of the splitter whilst i was out a few times but it seems fine, the splitter is still on!
Im going to make a filler panel like you have bok, ive used a piece of thick rubber on mine but its okay but sometimes when you drive it you can feel the air getting under it which sometimes makes the splitter wobble abit.
So i will be replacing that i think.

 

[BlackKnight1982]

The splitter is currently removed! under going so developments!
Ive been adjusting my suspension lately so the other day i slightly caught the front of the splitter on the tarmac while doing a bit of hard braking into a right hand bend that goes over a bridge!
Oops its fine just got a bit of a scrape on the underside!
Im going to keep this splitter for track days as its good for handling but its just a little bit too extended for a road going splitter i feel, im going to make another one which is shallower and poss a bit thicker maybe 9mm for general road use. I will just use my existing splitter as a template for all the fixings, but just make it a bit shallower.
The quest continues....

 

[warrenpenalver]

I do hope you used IRR and RCS reducing paint if your going for the stealth look!!!! 8)

 

[XIIVVX]

What are the physics of a splitter?

I'd have thought infilling between the bumper and the splitter would negate any aerodynamic effect and just increase drag?

 

[Dogsbody]

If you look at an Escoort Cosworth front splitter.
.

It's not massively bigger than a FRP one.

This what was written about its aerodynamics.

Front bumper with huge air intakes and low front spoiler with adjustable splitter. New low rear bumper. All this creates a car that not only counters the aerodynamic lift at high speeds but creates downforce too. At 180km/h the downforce is 45N at the front, with the splitter at it's middle position, and 190N at the rear

If you were to hold a tea tray out the window at 60mph sideways on, you would have great difficulty turning it into the wind.
The spoilers only work at SPEED, but are very effective :-D

Yes you loose speed, but speed in a car that's hovering on the road is not fun

 

[BOK]

What are the physics of a splitter?

I'd have thought infilling between the bumper and the splitter would negate any aerodynamic effect and just increase drag?

On my Puma I found out by accident (almost!) the effect the splitter has on the frontal aerodynamics.

When travelling forwards it creates an 'buffer' area of high pressure between the lower grille and the splitter. How do I know? Because when I attached my miniature 'splittercam' camera to the edge of the front splitter there is virtually no wind noise even when travelling at high speed...unlike what you might expect.

Without infilling the gap between bumper and splitter the wind travels faster under it than between the bumper/splitter, this makes the splitter act as a wing, causing up/down resonance, the end result was BANG!

Could do with a wind tunnel to try stuff out before going on the road