[rally_prep] Rally Build : Custom Dashboard / Wiring

[brumster 135 1 Cars]

I figured the last thing the forum needs is another "rally car build thread" so I thought, while building this new car, I'd maybe just put a project thread covering a few aspects of it that are little more interesting/challenging.

 

The car is a ground-up build of a stage rally car but most of the mechanicals are simply transplants from my previous car; the main idea behind the build was to do a really nice shell with more substantial cage and collate all the changes on the previous car (from over a 10 year period!) into a fresh build, so brackets can get put on first time in the right place, and so on. There's also a bit of weight saving going on, but nothing excessive. Anyway, ignoring all those aspects, I thought this thread could focus on the following as per title

 

Dashboard

I'm going to ditch the entire original peugeot dash moulding and make my own out of GRP. I did this many, many moons ago for a kit car I had, so it's familiar territory although I must admit it was a little hazy as my memory isn't what it used to be - proof if ever there was some needed that beer kills brain cells, I guess.

 

Wiring

I'm going to take the basic Pug GTi wiring loom and strip out of it all the circuits that serve no purpose in a stage rally car, partly to simplify but also for further weight saving.

 

Power Control Module

The standard fusebox is going, and in is stepping a MoTeC PDM15 power delivery module. This greatly simplifies wiring as all relay and fuse operations are performed solid-state within the PDM. It also gives you lots of flexibility because you can use software to configure the logic of all the inputs and outputs, and their relationship. The PDM15 has 15 input/output pairs and represents the budget end of MoTeC's PDM range, but again, there's not that many circuits for me to switch so it suits my needs for a motorsport car. The 30+ channel ones are SERIOUS money (as if the PDM15 isn't serious enough as it is).

 

Instrumentation

Very long-term (and not covered by this thread any time soon) I have a little electronics/microcontroller project to make my own AMOLED-based dashboard display solution specific to my needs, but that's a steep learning curve for me and I can't wait for that to finish before I can put the car on the road. So in the interim I'm going to use some off-the-shelf miniature LCD screens from RS Components to capture inputs from fuel sender, water temperature and fuel pressure sender. I'll re-use my existing SPA gauges to cover revs, oil pressure and temperature - and my rally trip meter can provide speed display. This means I can junk the entire Peugeot instrument cluster for a cleaner look, simpler wiring and possibly a minor weight loss too.

 

Anyway, scene set... here we go!

[brumster 135 1 Cars]

Car came back from the paint shop as a bare rolling shell, thus :-

 

 

First jobs relevant to this thread were to lay out the Pug wiring loom and rip out all of the superfluous circuits; to help me do this I say down and worked on some revised scans of the Haynes wiring manual, greying out the circuits I didn't need, to help me identify all the numbers/circuits that I could junk and those that I could keep. At this point I didn't plan to go with the PDM and the plan was to wire it all into a Wurth TRM board that I acquired from Autosports as a demo sample. The revised diagrams, in very high resolution so you can print and keep the detail, are available at http://www.giveitdeath.com/images/RevisedElectrical.zip. Speaker circuits, electric windows, central locking, rear wiper, heated rear window, side repeaters are all removed. The front driving light circuits came out because I run gas discharge spotlights on night events that run off a separate circuit anyway. Likewise, radiator fan was ditched because the PDM will control that directly by reading engine temperature off the ECU via a CAN bus, plus allow override via a button on the dash. Interior lights, heater, and related stuff like instrumentation lighting circuits got removed although the output for the instrumentation lighting will stay in a simpler form.

 

Basically lights and wash/wipe stays, although I have done one slight change-around and linked the front wash pump output to the REAR wash pump - this is because I'm going to run the rear reservoir pumping the front squibbers, leaving the engine bay a little clearer in that front left corner.

 

 

The black box is just a mini-heater that is again intended to reduce weight, although it will only feed screen demisting vents. At the moment all the connectors are left on if they still have a wire that I need, really more to help reference when I come to clip them and connect them. The reduced loom is now all in corrugated sheathing to keep it tidy and nice-looking, courtesy of Vehicle Wiring Products.

 

On the dashboard front, next step was to make up a basic wooden former in-situ that would get me the general dimensions of what I was after....

 

This means I can check the general dimensions, make sure it covers the steering column and clears the roll cage, and has the right positioning for reach when I'm sitting in the car. This former then comes out of the car and I started building it up in the convenience of the garage and the B&D workmate

 

At the moment it's at this stage :-

Still needs lots of flatting work on the "hump" which is the instrument binnacle. When it's ready, I'll take a GRP mould off it which will itself become the mould for the final product. It's slow work but important to take time on, I think, otherwise the end result could look a right mess. You can see I've basically used some sheet aluminium to provide a curvature to the whole dash, propped up in the middle with some wood underneath. This was then screwed into the MDF frame, the screw heads recessed and grinded off, then fillered over the top.

 

Yesterday the PDM turned up from my friend Nathan at Race Data Systems...

 

The main unit is the PDM15, of course, but also in there is the plug kit (MoTeC, as usual, know how to extract every last little penny out of you - robbing Aussie bastards), plug pins, the UTC/CAN adapter and the plug for the adapter onto the CAN bus.

 

There's nothing to the thing . It will get mounted on the bulkhead in front of the navigator, roughly where the old fusebox was. The big bolt in the middle is where your live feed from the alternator/battery goes onto it; the two superseal connectors then take the various inputs and outputs to the switch circuits, output circuits, earths and CAN bus. If I get time this weekend I'll start wiring it up...

 

That'll do for now....

[Henry 1.9GTi 36]

Lush.

 

Good luck with the project, its looking like a very perfected build. Something I'd like to do after the steep learning curve of the first build.

[brumster 135 1 Cars]

Ooo I forgot to mention, but it might be of interest to someone planning the same thing - I weighed all the wiring and plugs that got cut out of the loom and it came to just under 2.5Kg... so not a fat lot really, you might as well take a good dump prior to hitting the stage than go through all the hassle . Mind you, I kinda wanted to do it anyway to make it neat and more simple to follow/wire. It really didn't take long once you'd spent some time identifying the circuits to the wire numbers. I did a spreadsheet; I'll attach it in case it helps anyone in the future. You'd need to ensure that the circuits I'm getting rid off are the same as what you'd want to chop out. For example, I didn't need ANYTHING related to engine management so all the ignition and ECU related circuits, plus the subloom, are junked....

 

Ooo I've just realised I didn't weigh the ECU subloom in that 2.5Kg.... obviously a custom EFI loom went in in it's place, but it's certainly a bit lighter than the original Pug item.

ELECTRICAL-NUMBERS.zip

Edited April 1, 2011 by brumster

[brumster 135 1 Cars]

As part of the interim dash display I need to put something in there to show me water temperature and fuel level, at the least. To do this I picked up some Lascar PanelPilots. These are cracking little things for the money, £60 gets you a nice little colour LCD display with 2 analogue inputs that you can use to drive a completely configurable display screen.

 

 

They run on a wide voltage range supply so would happily sit on a 12-14v automotive feed (although I'm going to run them off a filtered 5v supply just to be safe on interference). They have a USB connector on the back, and you can then just plug them into a PC and configure up all sorts of display types over and above the basic digitial readout above - graphs, gauges, bar graphs/segments, min/max recording and so on.

 

The sensors I got from KA Sensors in Grantham thanks to a negotiated discount at Autosports again . The prototype board is just serving as a holder for the 5v supply and a few resistors to ensure the voltage scaling is accurate on the meter for the given senders in the image. I've bought another display which will give me fuel tank level....

Edited April 1, 2011 by brumster

[Alan_M 66 1 Cars]

Nathan of RaceDataSystems.co.uk lives next door to my mate where I've stashed a 205Mi and Clio 172. I was pulling parts off the 205Mi one day and he popped out to say hello, and flog me a camera system whilst telling me race exploits. Nice chap.

 

Be very interested in the wiring side. Something I want to do myself, but was thinking of making a new dedicated loom up rather than strip out.

[brumster 135 1 Cars]

Nathan of RaceDataSystems.co.uk lives next door to my mate where I've stashed a 205Mi and Clio 172. I was pulling parts off the 205Mi one day and he popped out to say hello, and flog me a camera system whilst telling me race exploits. Nice chap.

 

Chuckle; small world! I work with Nathan in Reading, hence the connection

[EdCherry 34 1 Cars]

Not just Motec that f*** you over on connector fronts mate, only company i've found so far that doesn't use connectors that you cant get elsewhere is Race Technology.

 

Will watch this with some interest.

[brumster 135 1 Cars]

You CAN get the connectors, actually - they're just Tyco (AMP) Super Seal series connectors, but I priced them up from Mouser and to be honest they were pretty much the same price. The connectors themselves are about £5 and £7 a piece, but it's the crimp pins that are the expense - about 40p EACH, and you need 60 of the feckers! I just figure if MoTeC were selling you over a grands worth of control module they could find it in their margins to throw in the connectors (seeing as it's pretty much guaranteed you'd need them).... ah well...

[edbar 6]

Looks great so far Dan, thanks again for the loom, going to start chopping it about tomorrow!

[brumster 135 1 Cars]

Thanks for the comments guys; it keeps me motivated !!

[mochyndu 0]

This is something Im going to be keeping an eye on.......keep up the good work

[brumster 135 1 Cars]

So today has been spent focusing a little on the dashboard. It's tempting to jump into the wiring of the PDM but I'm stuck at the moment with no dashboard to mount things in, so it would be kind of useful to get that aspect done. Also it's going to take the longest time-wise, because of the curing time for the moulds, so it's about time I crack on with it really.

 

 

Toiling away with the 80 grit... the instrument binnacle bit is the most fiddly... on with what I'm hoping will be the final filler before one more flatting session and she'll be ready to take a mould of.

 

 

My 1980's vintage Black & Decker Workmate, passed down through the years and still going strong - much better than the modern versions too :-)

 

 

And here you can get an idea of the cross-section of it, so you can see the curvature of the top panel.

 

 

Will leave it to dry now and hopefully, following a last bit of flatting, take the first mould - maybe next weekend if I have the time!

[brumster 135 1 Cars]

The gelcoat's just gone on; hopefully ready for the first layer of chopped strand in a couple of hours... ulp

[edbar 6]

Any updates yet?

[brumster 135 1 Cars]

The 3rd and final layer of the mould layup went on yesterday, so I'm giving it a few days before cracking it and leaving it to settle on the buck. Ooo the anticipation!

 

Electrical-side wise, I've made an aluminium plate to mount the PDM onto, and then affixed it all to the bulkhead in front of the navigator.

 

This morning I've been reverse-engineering the 12v->5v power supply for the in-car camera so that I can incorporate it into a little box somewhere, rather than the cigarette-lighter based solution that it came with. I mounted the intercom ready for wiring up, and started planning out the power feeds to it, the camera and the solid-state recorder.

 

Some other little bits have turned up, such as extinguisher piping, so I'm getting some other little jobs out of the way while I wait on the fibreglass side of things. Only problem with the dashboard side of things is it takes a lot of elapsed time, so I'm doing other minor things while I wait on it.

[edbar 6]

Good stuff! Are you making the dash to be lighter than standard? Would it accept standard clocks? Could be a nice sideline if so! Just finished my wiring and fitted another oil press sensor so all is now working, might do a custom wiring job next year as it still seems heavy/untidy.

[brumster 135 1 Cars]

The dash will almost certainly be lighter than the standard fitting, yes, but it's only the top half of the dash - imagine a straight line across at the height of the old heater controls; there's nothing below that. It's made for the job in hand - so no radio, no heater controls and so forth.

 

It won't take standard clocks, no, the 'binnacle' part isn't that wide. Will crack it off tomorrow and let it settle; will then get a feel for what the inner face is like and whether it's all going to work or not :-S !!

Edited April 24, 2011 by brumster

[brumster 135 1 Cars]

Well, I've just cracked the mould off the buck and I am WELL HAPPY

 

So to summarise the past few days...

 

First, PVA release agent goes on. This is a thin film of blue brush-on liquid that helps the final piece release off the buck/mould without bonding to it... on top of that goes the laying-up...

 

 

...and then this morning, off it cracks...

 

 

Top-side...

 

Unfortunately it grabbed around the instrument binnacle part - the "hump" that the dials go into - probably as a result of the high amounts of filler in there. This meant I had to destroy the buck in the process of removal...

 

...but that's no problem; it's job is done now.

 

Really chuffed with the resulting mould. Obviously it's not the final dash but it gives me a final idea of how it's all going to hold up and look. The surfaces are good, there's a few small bits where the gelcoat has bubbled and it will need a little minor repair but thankfully these are in corners that are not in sight on the final product, so it shouldn't make much of a difference.

 

I was wondering whether the final pieces would need strengthening putting into them but I'm wondering now whether I might get away without any - this mould is 3 quite thick layers and it seems strong enough, so the final dashboards might not need much in the way of a strengthening mould putting on the back of them... we'll see.

 

Time to let this mould rest for a week before I start laying up the first prototype dashboard out of it :-S !!

 

Nestled it into the car just to get a feel for things - it won't sit in fully because I've not moulded cut-outs for the rollage into the moulding (in case I make one for someone without a cage), so it hits the front bars at the moment. Obviously the final dash will be cut to clear them on each side, but it gives an idea anyway....

 

 

Other minor things, as mentioned earlier, is just the PDM mounted onto the bulkhead...

 

Edited April 25, 2011 by brumster

[edbar 6]

Top notch! Its a fantastic build mate keep it up!

[brumster 135 1 Cars]

No mega-updates for this weekend - been busy with birthdays - but managed to get the mould tidied up, repaired in a few spots where the gelcoat wasn't perfect, and I've just put the gelcoat layer in for the final dashboard that's going to come out of it :-

 

 

Black pigment for obvious reasons; final dash might get flocked (depends how the gelcoat comes out I guess).

 

Lots of other off-topic jobs done, such as the whole rear beam stripped rebuilt and refitted... other minor bits of wiring and so forth... one job has been to get all the large crimp connectors done, because I have on loan a nice Cembre crimp tool...

 

 

...for doing all the large-gauge battery and main power feed cables. That''s done now, including the feed into the ignition key, so it can be returned to it's rightful owner. So much nicer (and easier) having proper tools for the job...

 

Well, couple of hours for the gelcoat to go off and it's time to lay up the first layer of the dash...

[edbar 6]

Wont just gel coat reflect light like a barstuard? Flocking might be essential to avoid the glare off it.

[brumster 135 1 Cars]

Yeah, exactly, that's what I'm thinking...!

[brumster 135 1 Cars]

Well back from 2 weeks hols which has given the dash a nice chance to cure properly. Cracked it out of the mould and we have our dashboard.... here being cleaned...

 

For the first attempt, I'm very happy with it - certainly good enough to be used in the car, although it's not perfect, with a few blemishes as a result of shoddy taping and poor moulding in places...

No grumbles with these though - will put a little bit of filler on them, flat them up, then once the dashboard is flocked you won't know they were there.

 

Brushing the gelcoat in has left visible brush patterns in the finish if you look closely, so I think if you didn't want to flock the dashboard or cover it in someway, you'd need to think about spraying the gelcoat in the mould, as I've seen some people do on YouTube. Also left some release way on the final product which I need to clear off with some serious elbow grease! Overall, very chuffed though.

 

With much enthusiasm, I quickly dropped it into the car to get an idea for how it looks/sits.....

 

Edges only roughly trimmed for now, so yes it looks wobbly along the bottom edge

 

Popped the instrumentation in place with a bit of hole cutting and careful dremeling...

 

Need to find a flockers in the Midlands now - anyone recommend any place, or just as equally warn me away from bad'uns?

Edited May 21, 2011 by brumster

[rallysteve 22]

Constella

 

Did a great job on mine

 

Steve