Prawn and BigAls A3 Track Car

snowy said:

Our base software is highly reactive to weight distribution

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I think this is the key point.

Weight distribution on my car, and also relative available braking force at each end, is so vastly different to stock, that the system is operating so far outside of normal parameters that it no longer does it's job properly.

Given the size of my front brakes, and the extensive cooling setup I've installed, I really shouldn't be suffering from these issues. There are others with smaller brakes and no cooling that have no issues since an ABS delete, so I'm fairly hopeful it'll be a resolution to my problem.

If not, then it's something I'd need to do to go racing anyway, so it's not wasted effort

Battery and WMI are already in the back, so that's the main bulk of the above.

PSF and screen wash are such small items I just don't see it making a huge difference.

Agree with the concept though certainly.

Everything at the back is fairly redundant, so easily removed (and already gone)

Everything up front is fairly essential, so it's pretty tough to lose any great deal from the front end

Rainbird said:

Might rattle around a bit in the boot though. Better strap it down well.

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Altering weight distribution is about all the rear diff would be good for

FWD and proud!

I must admit, a fuel cell is something that's never appealed to me for the A3.

The stock system is mounted as low as it could possibly be, and is fairly far back towards the rear axle. it's well baffled, reasonably light weight, and has a decent built in swirl pot system which doesn't suffer from fuel starvation.

Any gain by moving the tank backward is potentially offset by mounting it 2-300mm higher up in the boot floor. I'm also not keen on the idea of mounting it inside the car due to the need for a firewall etc when doing so. I also need the full 54L capacity, as I use that amount 3x over on a single trackday sometimes!

In other news, I'm sick and tired of waiting on the few small valve parts I need that I ordered from a supplier in America.

I've now taken an £80 hit and ordered the bits direct from Supertech, and they should be here next week, so I'll FINALLY be able to get the ball rolling!

Once those bits are here, I'll book a week off work, and make some real progress towards getting the thing running again!

Ordered a set of head stands this morning, and will be ordering some valve spring compressors shortly too so I can swap these valves over myself.

For too long I've relied on the help and generosity of others on some of the more complex aspects of the car (and been incredibly thankful for it too), but I've gotten so frustrated waiting for these few small parts to complete that I've decided this last leg is going to be 100% driven by me. No way it can slip back then. No relying on others.

Once all the bits arrive, there should be no excuses to not get it running again this side of Christmas.

I really am starting to lose the plot having it sat in the garage broken.

In related news, these arrived a few weeks ago:



So they'll replace the 18 year old original hoses. Once they're on I'll measure up and order JCS clips throughout also. Any hoses not covered in the kit I'll replace with straight lengths and bends to suit.

I also had another go at the adapter plate last weekend.

I wasn't happy with the amount of thread left in the hole at all, so I got out the drill and decided to see what I could do with it, fully accepting it may well end up scrap.

To my surprise, after just a few seconds with a small drill bit, I started getting what looked like shards of thread coming out.



A few minutes later, and I got out what was actually the end of the original stud!



I then found a spare M8 tap, and cut it off at half length to create a plug tap.

I ran this down every M8 hold in the adapter plate, with good results. Including the wonderful damaged hole I've struggled with so much, and to my delight, it appears I now have 5 fully intact useable threads, which matches the other angled stud holes.

I'm now confident I can use this without issue, and without the additional of a helicoil.

IF, when I come to tightening it all up, I find it pulls through again, I have also considered overdrilling to M10 and using one of these:



I think it's all heading in a positive direction.

Thanks Big Bad

We WILL be going for a drive in the A3 on Christmas day.

This target isn't optional. It's been down too long, and we've lost another year of trackdays. Next year will be fairly busy too with Baby Prawn arriving, so the car MUST be sorted this year and ready to go.

From what I could work out, the 12 hose kit had a few extras for the over run pump, and I couple I couldn't figure out that certainly arnt on my car.

I decided to go with the 7 piece after @Tabsy said his were decent quality and fitted well. Anything missing I'll make up in silicon myself I think.

In other news I think we'll be ordering new springs shortly, after talking about them for over a year
This will be an interim measure to stiffen the car up, and won't be the ideal end solution as the rates I would ideally run will be WAY beyond what my v3 shocks can handle. And there's no point in overspringing the car to the point where it's no good.

Current thoughts based on experience of others is to go 10kg front and 8kg rear.

Good stuff Mark.

What spring rates are you running on the Bora also?

Hi mate

Cage is an omp AB105p 202h

http://www.ybracing.com/omp-ab105p2...swagen-golf-mk4-5-doors-only-inc-gti-98-.html

Hope that helps

Simply because that's what's in mine Ben.

At the time there wasn't a 3 door option, and the only difference is the tab to tie into the upper belt mount, which I ground off.

If there's a 3 door version I see no reason why it wouldn't fit, but I'd be surprised if the upper belt mount was in an identical location from the mk4 golf to a3 also.

I've actually done some work on the car today too!

Not much, but it's a start!

More on that later.

I've finally started working on it again!

First up, the bulkhead.

I stripped down my heatshielding, to reveal the mass of brake pipework behind.

I still had the original bulkhead sound deadening installed also, which had seen so many driveshaft failures, oil leaks, coolant leaks, and road debris, it weighed about 5kg and was probably a huge fire hazzard!

Obviously that had to go!



After removing the ABS pump and lines, i cleaned up the bulkhead, then set to work on the first brake line.

I mounted the T piece for the front split in an appropriate location, cut and bent the first pipe, flared both ends, and offered it up.

It didn't fit!

Argh.



It turns out, all the threads on the car are m10x1, apart from the 2 into the master cylinder! These appear to be m12 fine.

I cut the end off, and refitted one of the original fittings:



With a bit of practise the flares all seem to be coming out very well. I've found a drop of brake fluid on the pipe before flaring really helps get good results

So, attempt 1:



And it looked absolutely *****!



Lets try again:



Similar profile, but far less messy. That'll do.

Next up the front left wheel.
I started at the wheel arch end, replicating the factory shape as closely as I could:



Then moved onboard, trying to retain the stock pipe clips the whole way across the engine bay:



2 things to note when making brake lines:

If using copper, it absolutely MUST be clipped every ~200mm. Copper work gardens with vibration, and it allowed to vibrate around too much it can go brittle and crack.

You should also avoid a straight run between 2 fixed points, as it won't allow for any expansion or contraction with changes in temperature. S bends or similar before fittings are always a good idea to allow the pipe a little movement if required.

In this case, I'm using Kunifer, which is copper / nickel, rather than pure copper.
Kunifer is easier to work on my opinion, and nowhere near as prone to work hardening / cracking as pure copper.

Next up was the drivers side line.

I'd have loved to do this in straights and bends, but the space available just allow it, despite how it appears in the pic!




With it all back in and connected, everything fits, and everything clears without touching. There is 15mm between the two lines beneath the servo.



Last up for today I decided to mount the bias lever.

I wanted it within easy reach whilst strapped in. I had thought it'd end up back near the handbrake, but it just wasn't natural or comfortable to adjust when back that far.

I found there was a gap to the side of the gear lever that my leg could not get to as the seat stops it, so it can't be knocked.

I made up a quick bracket from some thick ali angle I had, drilled and tapped to m6 for bias lever, and mounted to the side of the shifter tower:



It's easily adjusted whilst strapped in, doesn't interfere with the gear lever in any gear, and I cannot knock it with my leg no matter how hard I try, so I think it's a winner.

You can see the lever position here:



I've rotated the lever, so quite literally, you pull the lever backward to bias the brakes backward.
Push the lever forward to push brake bias forward. I've mounted the lever high enough that is easily reached and not lower than the side of the seat, and it also allows me to form an S bend both to and from the lever for expansion purposes.

Busy week ahead, but next weekend I'll be back on it. Hopefully finishing the rear lines and making up new heat shields for the back of the engine bay.

I also need to make up a sealing plate / gromit for the gaping hole I gouged in the bulkhead all those years ago for the shift cables

Even though it's only small steps, it feels really good to finally be making progress on the car again

I'll be back!

So, it genuinely feels like I've waited a lifetime for this:



A whopping £112.58 later, these finally arrived:



Not even angry that I ended up buying them again from a different seller.

Money down the drain perhaps, but worth it now that I can finally make some progress!

Yes.

Pm'd you my reasoning. It makes zero sense now. I'm an idiot at times, and I know it

More progress today by way of postman pat!



Clutch disc is back and ready to go



And I've found my supertech valves and springs to double check the collects and retainer are correct



Hopefully have a day on it tomorrow.

Plan is to make more progress on the brake lines, and if that goes well, I'll pull the head and make a start on the valve swap

Progress at last feels good!

4x inlets to swap for supertech.

The rest are done already

Argh.

So, some more work was done, and visually, things went backwards again

The seats are out. the fuel pump is currently off, it's in more bits than it was on Friday!

I think I'm reaching the end of the doom and gloom phase, and soon I'll start to see progress and cheer up again.

I may even begin to take more pictures once I've got something worth of taking a picture!

Over the weekend I addressed lots of small jobs, mainly related to the brake lines.

So, Saturday started with finishing off the lines in the engine bay.

With the fronts complete, all that was left was to route the single line to the rear through the bulkhead.

Much care was taken to find a decent passage through the bulkhead, that'd bring the pipe out in a sensible location in the car that can't be kicked or knocked by either my foot, or my passengers.

Care was also taken to ensure that none of the pipes in the engine bay touched the bodywork anywhere other than the clip locations, and none of them touch each other at all.

it's not the most Pro looking job, but it's not 100% ****



This then runs inside to a joiner up on the tunnel. I didn't want a single piece all the way to the bias valve, because if the internal pipe is ever knocked or damaged, I'd need to remove the engine to replace the line in the engine bay! Adding a joiner gives me the option to replace either end independantly.

This hose actually looks neater in real life. I kinked it inboard immediately after the console so there's no change of my leg ever pressing on it, but it just looks odd from the angle of this pic!



Under the car to the rear axle, and time to plan the pipe runs back there.

First pipe to remove, the hardline on the rear beam:



Yay!

Not to worry, I've got a spare beam in the other garage, I'll go and get the pipe off that:



Yay (x2) These things are Sh!t.

So, 2x new rear hard pipes ordered with the ECP 30% code this weekend.

Next up, to fit the orange braided hoses I got YEARS ago but never fitted. This gives me a solid termination point to aim for when bending up the hard lines.

I offered the pass side braided hose up, only to find the stainless fittings don't go through the standard 14mm bracket holes!

D'oh!

Thankfully, I had a countersink bit which took it out to exactly 16mm, and the hose fitted fine:



On to the other side, and the standard connection location is facing up, and backwards, to meet the brake pipe that's run across the top of the fuel tank. it was also rusted SOLID.

Now, I didn't want to keep this location, for what I thought were 2 good reasons.

Reason 1: I didn't want to drop the fuel tank to get the new brake lines in. This seemed like an awful lot of work for what started out as a 'quick job'

Reason 2: Should I need to replace / retighten the lines ever in the future, I didn't really want them being in a totally unaccessible location. the 2 connections on the passengers side were easy to reach, but the standard location on the drivers side would have been impossible to get at should it need intention in the future, without dropping the tank again.

So, I looked at ways of modifying things to move the connection point downwards to a better location.

This is what I came up with:



I re-drilled the hole in the beam mount to fit vertically like the passengers side, then made a bracket that piggybacks onto the rear beam pivot point. it's still well up out of harms way, doesn't interfer with the fuel tank or pump, and brings the connection to a much more accessible location. All I'll need to do is 'massage' the new hardline to suit the new downward fitting position.

It's amazing just how much time these things take! Little things like working out the best route for the pipes. Finding ways to clip the pipes whilst drilling as few additional holes in the car as possible etc.

I'm now at a stage where both rear lines are installed from the beam connection, through the seat squab, and jointed at a T piece near the handbrake.

Final brake pipe to run this evening is from the Bias valve back to the T piece, then the new hardpipes arrive tomorrow, and hopefully I can get some fluid through it and see if any of my flares leak! That'll be the next nervous moment!