Yeah and finding 2-4 MPG on something that gets 8MPG is enormously harder than finding it on something that gets 28MPG.

My understanding is that you can get TOO low. When it touches, it loses d/f, the front pops up and regains d/f, nose drops and it touches again, loses d/f ... rinse and repeat. Known as porpoising I believe. We had a 4 litre 911 doing it in the braking area at the last sprint meeting, clearly audible from the viewing platform.

The splitter needs airflow to work, so when it is cut off it no longer works. It would be dependent on how much of the splitter is touching too I guess, if you have a relatively pointy splitter shape only the extreme tip may be touching and that may not be such a problem, whereas a straighter splitter may be touching along a greater length.

From your description, it sounds like the height under brakes is already very effective. Maybe dropping it a bit more will improve both braking and cornering. I have been thinking about ways to limit the dive under brakes so that the splitter height change can be managed - heave spring anyone? Or maybe a skid which would 'protect' the splitter, and keep it a few mils off the track ... hmmm

I look forward to hearing how you go.

https://scontent-cdg2-1.xx.fbcdn.net...ce&oe=563BD44A

the effect was so strong on my car is actually damaged the wing by trying to pull the aluminium end section out of the wing, had to run a carbon rod from the bottom of the endplate to the wing upright in the end, you can see it best on the right hand side

IME, nothing survives cones forever. We use alumalite for our dedicated autocross car, and it has been surprisingly durable.

A REALLY big hit at high speed will put a small dent in the leading edge, but won't destroy it like the aluminum sheet in your pic. We run it pretty low, so it slowly starts grinding off the lower sheet of aluminum.

We're still perfecting the design/height/etc. The biggest area that needs improvement is in the mounting brackets. But our first alumalite blade lasted one full season of heavy autocrossing with three/four drivers per event.

A Subaru I drove for a while had a custom splitter that was two layers of carbon on either side of an aluminum honeycomb core. For durability it had a wood leading edge and a layer of kevlar on the bottom. It was really awesome, and super light. But for the cost/trouble to fabricate (expensive materials and very labor-intensive to build), it was probably not worth it over alumalite.

Neal

Uhhhhhhhhh can i get some details on your car? :drool:

yeh sure,

I spend alot of time reading miataturbo as its great for technical info whether it be aero, chassis or engine/tuning development(i do all my own mapping so looking at the megasquirt ignition tables really helped)

My car started off as a series 1 lotus elise(wasnt avaliable in the US) I then added a special lightweight exige body(my own mix of composites)

It weighs 715kg(1573lbs) runs 16x8(225) and 17x9(255)

Aero wise its a complete flat floor from front to rear, underbody and diffuser is aluminum, side skirts are 3mm dibond(aluminum/plastic) with 5mm rubber skirts, splitter is 1mm carbon each side with a 10mm nomex honeycomb core(hardest bit is getting it stiff enough to take the downforce when being attached to a composite crash structure.

the front wheel arches are vented from the top to release pressure and all of the sill behind the front tyre is removed to again reduce pressure

the splitter also has diffusers and end fences, the diffusers are set at 10 degrees relative to the ground when the car runs a rake of 1.5 degrees.

The diffuser is raked at 12 degrees to the ground at again 1.5 degrees of rake.

the wing is a simon mcbeath 183 dual element wing attached to home made pure carbon fibre uprights

the front splitter leading edge is 70mm from the ground and will start to skim the ground at 130mph, i havent had to hit the brakes hard at that speed yet as most UK tracks dont have long enough straights, i will probbaly have to up the spring rates to avoid the splitter grounding hard when braking.

I run 700lb front springs and 900lb rears

One of the reasons I like this forum is the engine info everyone is very open to give, I run the OEM Rover 1.8 twin cam engine which is a very lightweight engine(the block weigns 8.5kg) it is known over here for blowing head gaskets and cracking the very thin liners(its basically a 1.1 engine designed to be 75bhp but massively stroked and bored) so I thought it would make the perfect engine to throw a big turbo onto it and a load of boost.

At 22psi peak and 20psi hold its around 320bhp and 300ftlbs, im still running OEM engine components, the muffler bolts directly onto the turbine housing and sticks out of the lefthand side quarter panel

Here are a few pics, sorry for hijacking your thread but I do enjoy aero and make all the components for mine myself with whatever I can find lying about.

I would like to maybe chat to The Pass on facebook one day about his aero but hes never popped on my suggested friends list yet.

https://scontent-lhr3-1.xx.fbcdn.net...e1&oe=5651581D
https://scontent-lhr3-1.xx.fbcdn.net...23&oe=5638B81E

you can see the cut away sill and door to expose more of the front tyre
https://scontent-lhr3-1.xx.fbcdn.net...02&oe=56823174

rear mounted intercooler ive just installed
https://scontent-lhr3-1.xx.fbcdn.net...5f&oe=5651F88C

https://scontent-lhr3-1.xx.fbcdn.net...53&oe=563DB466

The car infront on the picture earlier is a lancer evolution which had its body cut off and a 205 T16 Group B body but on, its 400bhp 4x4 and weighs 1000kg.

Holy crap, that's cool !

Menacing, that's the word for that thing.

:drool:

That lotus is so rad!!

Definitely not a problem.

Why haven't you put end plates on the canards? Seems like an all-out car like this would have them, especially on canards with that much surface area.

Lee I have been following your lotus for some time, aren't you running a Simon Macbeth Aero?

Another splitter
 

Just made a new splitter/air dam.

As you can see from the pictures there is a reason I made a new one, I decided to run out of talent on a lap and tested the snow plow potential.

Original splitter/air dam was constructed from 3mm aluminum, and held by 3mm ally brackets to the rails, and some of those thingies you can see at the front. It was also had a set of the large garage vary canards, and custom end plates either side.

Splitter 1

Dollars spent: $200
Hours spent: 5
How effective: 3
0=slower, 1, no improvement, 2 =slightly better,3= big improvement
Materials used: aluminum
Size/thickness of materials: 3mm
Bracket location: rails, screw holes for undertray and front stays
Tracks tested on:Lakeside QLD and QLD Raceway
Race/TT class built for: TT/TA

Splitter 2

Dollars spent: $200/$300
Hours spent: 20
How effective: to be tested tomorrow
0=slower, 1, no improvement, 2 =slightly better,3= big improvement
Materials used: Coreflut centre, 3 x Layers Fibreglass, 2 x Layers Carbon CF in places, 4mm Aluminum bracks, That plastic roll stuff 3mm
Bracket location: Rails and front stays just behind dam
Tracks tested on: tba
Race/TT class built for: Fun

Brake ducts are SINGULAR with a custom set of 3D printed bellmouths from a friend at Dreamfarm.

Endplates to be finished and added. Diffuser parts to be made on another splitter and swapped out (with more CF).

Its on the list of things to do, just havent got around to it yet, since the canards are curved I will probably just mould a vertical section each side in carbon.

Interesting that alot of race cars dont have the vertical section and allow spill off to travel around the outside flanks of the car to energize and keep the air attached rather than forcing the turbulent air over the car into the clean air heading to the wing with reduces air wing efficiency and downforce

rear wing is a simon mcbeath 183 dual element wing with my own endplates.

that video is of me but wasnt made in the way I wanted and was more about youtube controversy than actually giving the information i wanted to get across.

the wing in that video was moulded off a 2004 honda BAR monza spec f1 wing then extended out to 1750mm, its still in my shed as im not sure what to do with it.

Where did you source the turnbuckles from?

From Bunnings, which is a hardware warehouse. Also boating places seemed to have the same.

Looks good Tim, hopefully see you on the track soon.

Passey - how would you go about getting front downforce on the Eliminator? I'll be starting one soon and was thinking about adding a wing to the front - Indy style.


https://www.miataturbo.net/attachmen...ine=1439812553

https://www.miataturbo.net/attachmen...ine=1439820167

This is how, obviously.

Funny, I just came across an ad for these last night surfing craigslist..

That thing is so aerodynamically challenged you're better off focusing on mechanical grip. :giggle:
A front wing could be effective, but this is a street car - you really don't want to be driving around with a wing acting as your curb feeler. And you'll never match it with rear downforce - there's pretty much no way to put an effective rear wing on that thing unless you mount it two feet above the cage tubes.

-Ryan

Loving this car.