BEAVIS' White Track Car

[beavis]

Spent the weekend doing some bits and pieces on the car. (The Mrs is away on holiday)
Fitted up my lightened doors... made frames from some alloy tube to attach the polycarb windows to.
Stock doors weight about 25kg ea. These doors are 10kg, incl hinges.



Replaced the mounting bolts for the wing with some nice hex rounded head bolts. Still have yet to replace those dodgy end plates.


Took the wing and wing mount off. Replaced the wing mount bolts with hex rounded bolts also.


Here's a shot of the wing and its three elements. Delightful.


You may wonder why I removed the wing... well firstly, I wanted to reinforce the steel brackets that the wing bolt to.
I welded in a bit of a gusset. My gassless mig does nice dodgy welds... here it is after a hit of flat black, makes it hard to see exactly whats going on.


In fact I flat black'd the whole rear because flat black is the best.


The second reason I removed the wing was to re-install the rear bumper which had been off since the wing went on.
But first, it needed more trimming.
Before:

After:


Now you can see why I flat blacked

And had to do some extra cutting to fit the wing. Sadly I neglected to get a shot of the clearance around the wing mount once it was reinstalled.


Also removed the flat floor, skirts and diffuser. This is probably the first time I have shown you this... you can see the mounting holes and bracketry. You can also see i have flat blacked the parts of the flat floor that could be visible. The composite panels come in white which is a bit too.... erm, white.... for my liking.


Diffuser, this needs upgrades soon also.


Closer shot of things, the vertical piece you see is the wheel spat that normally lives in front of the rear left wheel.


There was a fair bit of crud built up on top of the floor, general dust and dirt. Thankfully no oils!
One issue however is the exhaust heat has certainly caused some issues for the plastic in the panel, there's ripples and bubbles along the areas near the exhaust. Perhaps i should have installed some kind of heat reflector. Or a cooling duct.


Lastly, I started work on a revised front splitter.


Here is the general shape taped out, I haven't finished this part...
Gonna wake it interesting getting on the trailer.


That's it for now. I am away on holidays for a little while so I wont be able to do much more for a week or so... but stay tuned.

[beavis]

Here's a finished pic of Boot and wing from last time:


Anyway, I resumed work on the splitter:


You can see it sticks out the width of the bumper a fair amount, however it lines up nicely with the top edge of the guard:


And the structural work is done. Its all bolted/screwed/riveted/taped on. Note the wheel spats hiding the front wheels.


And painted:


Also made some canards, this is the end result:



Had to make some little ramps on the trailer to stop the splitter from hitting the trailers front edge:

[plohl]

That's pretty epic

Did you intentionally make the splitter look like it has a sharp edge?

[greenMachine]

That's pretty epic :

+1. Great job Brendan! That is a lot of work you have put into all that aero kit, and a lot of thought.

Did you intentionally make the splitter look like it has a sharp edge?

Did you think about hinging the splitter? This might ease the loading problem, and might make it a bit more survivable in an off, or over the kerbs?

I see that you have trimmed your rear bumper to leave a big gap between it and the top of the diffuser. Is this to try and draw more air from between the undertray and the diffuser, perhaps for cooling the gearbox and diff?

[beavis]

Did you intentionally make the splitter look like it has a sharp edge?

No, I was thinking of giving it some colour there, not sure what colour yet however.... I would like to think a bright blue would work.

Did you think about hinging the splitter? This might ease the loading problem, and might make it a bit more survivable in an off, or over the kerbs?

True, would take a bit more redesign to do that, perhaps in the future.
I would like to do a similar hinged design for side skirts, ala 70's F1 style

I see that you have trimmed your rear bumper to leave a big gap between it and the top of the diffuser. Is this to try and draw more air from between the undertray and the diffuser, perhaps for cooling the gearbox and diff?

It is to allow easier mounting of the wing, and to catch less air as the bumper is like a big stupid parachute.

[lightyear]

Nobody is going to believe you have a stock driveline now. Looks like a time attack car for sure.

Should drop a couple of seconds if that front end aero works. We know the wing is capable.

You should make up some side fences in a triangle-ish shape. And bring them to winton incase you need more front downforce.

[plohl]

No, I was thinking of giving it some colour there, not sure what colour yet however.... I would like to think a bright blue would work.

Yes. I think that would work

It does look like a time attack car. Keen to see hear how the aero goes.

[lightyear]

Still no video of the 1:37.6 lap of Winton on Sunday?

Would have to be the quickest MX5 time in res open? With new tyres you could claim quickest outright time in the club at Winton.

[zossy1]

Have you ducted air into your front brakes? You may have issues if you don't - ask me how I know.

[davekmoore]

Brendan was kind enough to take me as a passenger around Winton yesterday. Even with the extra 100kg of me I reckon he was doing around or under 1:40s whereas the quickest I'd previously done was a 1:48.xx. This 10% difference in time is immense in terms of extra G forces in turning and braking and it was a great experience which helped me get quicker, albeit still nowhere as quick as Brendan. It also taught me how frustrating it is for someone who's quick around corners to be slowed down on a hot lap by someone who's only quick on the straight bits (that would be, for instance, me).

After completely junking my front brakes on a recent track day I was only able to take part at all yesterday because at the last moment Brendan found me a spare pair of otherwise unobtainable front rotors and even helped me fit them on morning of the event, causing him to be delayed getting to scrutineering.

Thanks again to Brendan and others from the MX5 Club who helped me on the day, again. If there's anyone reading this who is considering joining the MX5 Club, hopefully this will help you decide it'll be a good move.

[smy0003]

I wouldn't mind a ride, Brendan!
Hahaha, sounds like a blast!

[greenMachine]

Brendan, just looked at the photos posted in the other thread. I see that the splitter hasn't stopped you using the kerbs!! And from the photo, looks like it survived ok?

I think it is the same photo, but your wing appears to be about zero AoA - I would have expected you to run more, maybe not max but mid downforce for Winton (assuming long circuit).

Or is the diffuser sufficient by itself for that circuit? Any thoughts on the usefulness of the diffuser, compared to the wing?

[beavis]

Still no video of the 1:37.6 lap of Winton on Sunday?

I'm trying, I need one of those fancy MAC laptops that Ben has. My Asus laptop is too old but I'm not spending money on things like that.
I hope to have a video up tonight.

Have you ducted air into your front brakes?

I've not had problems, provided I use the right pads. I used to have ducts, removed them for a drag reduction advantage.

Brendan was kind enough to take me as a passenger around Winton yesterday.
Brendan found me a spare pair of otherwise unobtainable front rotors and even helped me fit them on morning of the event.

Always a pleasure, it's fun taking people for a spin, shame its too loud to hear anything.

I wouldn't mind a ride, Brendan!
Hahaha, sounds like a blast!

If ever there are passenger rides at an event, just ask me.

Brendan, just looked at the photos posted in the other thread. I see that the splitter hasn't stopped you using the kerbs!! And from the photo, looks like it survived ok?

Where are the photos?!?! Yes, I hit the kerbs a bit on the weekend, but certainly less than I used to. The splitter is slightly damaged and in time will need replacing. Hopefully one day I will find a more damage resistant material.

I think it is the same photo, but your wing appears to be about zero AoA - I would have expected you to run more, maybe not max but mid downforce for Winton (assuming long circuit).
Or is the diffuser sufficient by itself for that circuit? Any thoughts on the usefulness of the diffuser, compared to the wing?

Airflow along the fastback carries a greater angle of attack than parallel to the ground, so I don't want to go too aggressive.
At the moment the Wing is not angle adjustable, however that would not be hard to change with just a few holes drilled.
Sadly I don't have any solid before/after data, other than lap times. It'd very hard to judge the Aero by feel, as it is always an ever changing progression.

[greenMachine]

http://www.marisagangemi.com/Motorsport/Winton-24th-of-August-2014/i-CX98s8h/A

[beavis]

Was at Winton last weekend with the MX-5 folks, day was run by AROCA and went pretty well. Dont think there were many casualties for the day.
First time out with the latest spec of aero. It's hard to judge which parts are working and which parts aren't, but I certainly felt like I could go faster than anyone else through the sweeper.
I have some ground clearance issues now, the splitter its scraping on the hard corners where there are lots of curbing.
I also went wide on the last corner and bottomed out on the kerb, so I'm going to have to lift the car up and check for damage to the floor.
All in all, a pretty good day, managed 2secs quicker than my previous best, which is quite a lot.




So anyhoo, video below of my 1:37.6 lap at Winton Long