How strong does a front splitter need to be?

[BLAKTOOTH]

Serious question. If you believe all the DIY'ers on the internet it needs to be strong enough to flip rhino's. I'm not entirely sure that's a necessary requirement you know? Would seem most people advice making it from ply and supporting it with fabricated brackets and rods. Doesn't seem unreasonable as ply is cheap and easy to work with. Downside is it's heavy, rots and looks a bit pikey.

Others have gone the sheet aluminium route or fancy pants carbon fibre. Aluminium is a bit trickier to cut at this size and, well, unless you are a bit handy carbon fibre's a bit beyond most. Plus I'm not convinced you'd be able to stand on either (this seems to be the offoicial way to prove your splitter is sound, don't ask me?) And with how low my car is Carbon would last about five minutes.

I used to drive around with my flappy FRP bumper wafting around in the breeze. It was very evident from the pics taken at Snetterton a few years back that it was very bendy. I bought some 3mm ABS sheet and made up a splitter/undertray. This strengthened the bumper a lot more than you'd think and held up to a lot of road abuse. Winner!

I now have a new bumper, that's nice and flat at the bottom so needs a new splitter. My question is, what to make it from and how strong does it need to be? at the moment I'm thinking of another ABS piece or aluminium sheet. I'm not convinced Ply is the way forward as it will weigh the best part of 10kg and look a bit turd.

This article suggests that elephants do not need to perch on it for it to be affective.

http://aprperformance.com/index.php?...sk=view&id=174

Discuss...

[BLAKTOOTH]

Just to add, I use my car on track so want the splitter to be functional rather than cosmetic. I'm also hoping to fit a proper wing to the rear to balance things out.

[Mark]

Cant you use an OEM one like a Laguna one?

Or a M3 one like this



i imagine they might be fortunes though.

[Johnny]

ultimately the biggest force the splitter will encounter is the time you mow down a domestic house cat on the way home one evening

so ... lets say a domestic cat weighs 8 lbs and is traveling at 6mph towards you ... and you car weighs 3000lbs and is doing 60mph towards the cat. ...... now assuming the cat gets hit by the centre of the splitter straight on, then the resulting energy produced from the collision is equal to 1572 Joules. If the cats head is cleanly severed that amount of engery will launch the cats head down the road for about 15686 feet with an initial speed of 214mph

all in all enough energy to power a light bulb for 26 seconds

IF, we convert this engery into stopping force, the splitter needs to be able to hold 94lbs .. which is 42kg

so I say ... 42kg !!!!

[BLAKTOOTH]

Cant you use an OEM one like a Laguna one?

Or a M3 one like this



i imagine they might be fortunes though.

And they won't fit a 200? Looks good though.

ultimately the biggest force the splitter will encounter is the time you mow down a domestic house cat on the way home one evening

so ... lets say a domestic cat weighs 8 lbs and is traveling at 6mph towards you ... and you car weighs 3000lbs and is doing 60mph towards the cat. ...... now assuming the cat gets hit by the centre of the splitter straight on, then the resulting energy produced from the collision is equal to 1572 Joules. If the cats head is cleanly severed that amount of engery will launch the cats head down the road for about 15686 feet with an initial speed of 214mph

all in all enough energy to power a light bulb for 26 seconds

IF, we convert this engery into stopping force, the splitter needs to be able to hold 94lbs .. which is 42kg

so I say ... 42kg !!!!

Fat cat's are an obsticle worth avoiding but foxes and badgers often cause more damage, b'stards! I reckon with that thinking a nice sharp ally tray will work well. Like a knife thro....

[igralec]

My splitter encounters the pavement at 5mph when i park too deep in the parking space from time to time

[Actual_Ben_Taylor]

I recall Jez's splitter ripping itself from the mounts at Sneterton, so guess they need to be pretty sturdy...

[BLAKTOOTH]

I recall Jez's splitter ripping itself from the mounts at Sneterton, so guess they need to be pretty sturdy...

My 3mm ABS splitter took a beating and never fully dettached. It used to scrape on bumps and ramps and it really protected the GRP bumper. Only time it came a cropper was when we ploughed through the tall grass at 100mph+ at Bedford.

[sideways14a]

If you regular drive roads with badgers near them then you will want to make the splitter out of 3 inch thick titanium.

Even that might break if you hit one of the big buggers.

[Actual_Ben_Taylor]

My 3mm ABS splitter took a beating and never fully dettached. It used to scrape on bumps and ramps and it really protected the GRP bumper. Only time it came a cropper was when we ploughed through the tall grass at 100mph+ at Bedford.

Did it go all the way back under the engine?

[BLAKTOOTH]

Did it go all the way back under the engine?

It was fitted to the front cross member which the oem undertray was timmed back to. Sort of semi flat floor/undertray if you like. The bonus from being made from ABS is it was easy to cut with man scissors and flexible enough to fit the curves and angle of the Bomex bumper. It wasn't rigid enough at full undertray size.

[piman2k]

For your splitter to be functional Lee, it needs to head back under the engine. Then you've got a much, much bigger pull down on the car because of the surface area and that's why they have to be strong. If it flexes and changes in attitude, then it becomes worthless.

Ply's fine, marine ply is better as it's treated and weather proofed.

[Mark]

Then you have to look at it being easy to remove/fit for doing oil changes etc.

[-ghost-]

Its the mounting holes that we found to break it never came off but 2 times the area around the bolt holes had cracked even with huge washes. He found a local place that can cut (cnc) a plastic sheet(like perspex but its stronger and I can't for the life remember whats its called) they could also put curves in it to channel the air.

One other thing worth noting is is your going past the engine or firewall You must add a few vents in the splitter as it gets a tad hot in the engine bay after


I've seen a couple of people use plywood but always wondered if it was heavy? and doesn't it get a little hot and burn?

[Johnny]

Heavy is good .... It means you get downforce at 20mph


Sent from my iPhone using Tapatalk

[BLAKTOOTH]

Do you know what, my car's not a "race car". I think I'll stick with a plastic splitter. I know it won't fall off. It protects the bumper and it looks alright. I don't care if it won't allow me to drive upside down in a tunnel.

[piman2k]

Dude, stick a bit of ply under your car, bolt it to whatever you can, make it go as far back as you can, and go for a drive. What have you got to lose?

[-ghost-]

I think the op means bumper extensions not splitter?


This is just right.

[daveyboydave]

Most splitters are just for cosmetic purposes and don't need to be strong. This includes almost all OEM splitters. As the photo above shows, a proper splitter (ie for aerodynamic effect rather than aesthetics) is as low and as far forward as possible, and extends as far back as possible. Such a splitter is there to generate downforce; it follows that if it generates 50kg of downforce, it needs to be strong enough to survive 50kg pushing down on it. This is why the 'standing on it' test is pretty sensible.