Prawn and BigAls A3 Track Car

[<tuffty/>]

RE the ABS issue... the reason it complains is due to lack of comms... so... why not plug an abs unit in... or a butchered one that is at least electrically operational...

I am also sure I have read somewhere of folk clever enough to be able to read and reflash instrument code to enable/disable stuff but for the life of me cannot remember where

<tuffty/>

 

[Prawn]

What a great idea PT. I'll look and see if the controller can be split down from the main body and left plugged in and hidden. But it wouldn't be the end of the world to leave the unit in place to avoid the evil multiple beeps. Good thinking

in other news, I cleaned the BMW today:

And in 6 hours time I'm leaving for the Nurburgring

Have a nice weekend folks!

 

[Erikn89nl]

in other news, I cleaned the BMW today

What sad news...

And in 6 hours time I'm leaving for the Nurburgring

Happy news! enjoy!

 

[Prawn]

Well, Germany was awesome. Even if we didn't get on track due to poor weather!

Dave had a good time, all 3 of him!



In A3 news, I'm still waiting on the valve retainers and collects from the states, which is getting frustrating.

I have decided that I'm going to take this opportunity to do an ABS delete though whilst the engine is out, and today I've ordered a Tilton rear bias valve and all the pipework I need to replumb the whole system

 

[SHUk]

Bob, I'm sure you've seen these.

Surely they are next after the hybrid?

Do you know where I can pick these up from please?

Thanks

 

[badger5]

http://www.innfab.com/store.html#!/...nt-Tubular-Control-Arms/p/21595737/category=0

 

[StaceyS3]

Sorry to drop in your thread prawn but kind of relevant.

These are now available which allow caster and camber adjustment unlike IDF.

 

[Prawn]

I like those very much Stacey!

Seeing as it's relavent, what's the retail on a set of those arms?

I Much prefer the 2 part design allowing independant caster adjustment.

 

[badger5]

price of those babies stacey?

 

[StaceyS3]

http://prorace-engineering.com/MK4-...f-A3-S3-TT-Race-Suspension-RACECONTROLARM.htm

The site hasn't been updated yet for the revised design. The new ones pictured above are stronger and easier to adjust.

Price is the same as previous version but will be looking to do a group buy on the arms and subframes in the next month or so.

 

[Prawn]

So, I've held off posting this for a while, I wanted to wait until things were a little further along before saying anything, and I've still not posted anything on facebook because people are too nosey on there, but if you're in here you've clicked on my thread and decided to read this, so despite it being more public I oddly prefer it

I am VERY pleased to announce, that Victoria and I are expecting a little boy, to arrive in march 2017




The Team Prawn Racing Driver line up will soon cover 3 generations

 

[Gazwould]

Wonderful , congratulations .

 

[george_seamons]

Wow, congrats dude

 

[craigt1985]

Congrats mate! Turbochargedminiprawn.

 

[scotty_24]

Congratulations mate!

A3. Game Over ha ha ha

 

[craigt1985]

What are the rules about rear/forward facing baby seats in a bucket seats?

 

[tcg]

Congratulations.

Can't wait to see the mods you put on his pushchair,another thread starting?

 

[g60leigh]

Congratulations bud. Very happy for you


Sent from my iPhone using Tapatalk

 

[Westy]

Congratulations team Prawn. Best keep hold of that BMW touring mate, you'll need it!

 

[Prawn]

Congratulations team Prawn. Best keep hold of that BMW touring mate, you'll need it!

You mean the one I conveniently bought 9 months before March?

 

[Erikn89nl]

I knew it! ...literally congrats again mate

 

[nobbybonez]

/life
congrats fella

 

[Golfyste]

Congrats again dude

 

[S3 Hilife]

Congratulations


Sent from my iPhone using Tapatalk

 

[StaceyS3]

Congrats again mate

 

[Jeriho]

Congratulations Prawn.

 

[A19quattro]

Baby prawn, back of the net











OK so it's a shrimp, closest I could get, Congrats mate

 

[desertstorm]

Congratulations to you and Victoria. Great news it's in March and not in the middle of the track day season. Well planned.

 

[bigal 1]

Congratulations.

Can't wait to see the mods you put on his pushchair,another thread starting?

I have a spare 13 bhp Briggs and Stratton from a garden tractor I scrapped. Who knows. ???

Problem is, it's a pull start.

 

[Lavis89]

Congrats guys!

 

[HTC]

Excellent news for the Prawn Racing Team ..... Proper jealous. Me and the missus have been trying for ages for kiddie.

Wishing you guys all the best!

 

[badger5]

anyway...................

back to cars

 

[Essflee]

Congratulations Prawn, boys are cool !! Lol

 

[Prawn]

Back to cars

This arrived last week:



Along with this:



A few of these:



3 packs of these:



And also these little bits!



Following several years of chasing a braking issue, I've decided to delete the ABS.

As standard the cars mechanical brake bias is largely rearward, but the ABS controls brake distribution and the end result is that the fronts do almost ALL of the work, with the rear brakes almost entirely shut off by the electronic bias control.



Whilst the rear brakes don't need to do a lot, I'm of the belief that mine currently are doing nothing AT ALL, and overloading the front brakes. This is potentially backed up by the fact that front pads last me 2-3 days MAX, and rear pads last 4 years. the weight distribution is 65/35, but the brake distribution is more like 95/5.

By simply deleting the ABS and replumbing the system, you end up with a 50/50 pressure split to front and rear, as is the mechanical bias from the factory. With no ABS to intervene, you end up with too much rear bias, and the rear locks well before the fronts do.

Adding the Bias valve will allow my to dial back the rear brakes until I'm at the point where all 4 wheels are doing as much braking as possible, which even if it's only a 10% shift rewards, will make a huge different to the front brakes, which currently struggle.

 

[snowy]

Congrats - enjoy the peace whilst it lasts

dial back the rear brakes

imho you need to ponder why the controller deciding to sending all the pressure forward

ie weight distro and front/rear spring rates

Otherwise you might find even a 10% rear shift just destabilises the car/reduces reduces overall braking

 

[Prawn]

Whilst I don't disagree, it's safe to say that I'm operating well beyond the intended use of the system as it came from the factory. So much of how the car was built is different, the braking effort at each wheel, the balance between them, the weight distribution. I think I'm fighting a losing battle trying to retain the system.

I've argued in favour of the ABS for years, and gone 6 years without deleting it, but through countless brake setups this one issue has remained, and others with similar setups have suffered it also, many of whom have cured it by deleting the ABS and taking control of their own bias.

It'll definitely take a bit of setting up, to learn what works in different tyres and in different condition, and I'm well aware that my driving style will change also and I could well be slower at first, but it's something I want to try.

It's also outlawed in many race series anyway, so I'd be forced to remove it sooner or later.

Whilst the engine is out, now just seemed like the ideal time to try it.
I'll not be destroying anything that comes out, so it can all be reinstated in future if needs be.

Time will tell I guess

 

[snowy]

tbh I wasn't defending the ABS, simply thinking about what it may be telling you

Upgrading the ABS system to motorsport ABS is megabucks

 

[badger5]

Congrats - enjoy the peace whilst it lasts



imho you need to ponder why the controller deciding to sending all the pressure forward

ie weight distro and front/rear spring rates

Otherwise you might find even a 10% rear shift just destabilises the car/reduces reduces overall braking

The pressure is not decided to go all the way fwd it is mechanically biased that way,
You are correct re the f/r balance, and I've seen prawnys car dive like a mofo under braking, so seriously under sprung front end. rear brakes not needed the wheels are almost airborne - lol

 

[Prawn]

The pressure is not decided to go all the way fwd it is mechanically biased that way,
You are correct re the f/r balance, and I've seen prawnys car dive like a mofo under braking, so seriously under sprung front end. rear brakes not needed the wheels are almost airborne - lol

This is true!

Whilst spring rates don't ultimately effect the amount of weight transfer, they do most certainly effect the rate of weight transfer, and with mine being SOOOO soft it transfers forwards VERY quickly, and the car dives severely, with the rear wheels quite literally trying to endo! I think this is closely linked with the bias control shifting extremely far forwards.

Spring rates are on the list for this winter too

 

[snowy]

The pressure is not decided to go all the way fwd it is mechanically biased that way

Do you mean Prawn car's ABS doesn't behave normally ?

The ABS unit anti-bias/balances the front/rear distro as a core function

Our base software is highly reactive to weight distribution

Hence one of the several reasons I use close to neutral weight distribution