Rallyrep in action

[Tim C]

All the way back up to Castle Combe again tomorrow for the final sprint/event of the year . Shame we couldn't have left the car up there somewhere last Saturday .

Weather's looking promising, fingers crossed. Hope all last weekends practice will do us some good .

[Isimmo]

Good luck Tim, have a good'n

[Audi Derek]

Weather does look good for tomorrow best of luck..



..

[Tim C]

Good day yesterday . Weather was good, warm at times when the sun peeped through. We even had the chairs out and had lunch on the patio (trailer).
Yet the air temp was quite low, so the car went well .

It was tricky getting back into sprint mode after doing ADI last weekend. I was even looking in the mirrors on my first practice run .
At ADI we were cruising a little bit, accelerating through the gears as we would normally do but not pushing quite so much through corners (or being held up ). Soon got back into the groove though, braking later and deeper into the corners .

I started the day a second or so ahead of Andy and managed to maintain that gap. There were some racey looking Scimitars in our class, but they didn't quite have the pace.
We also kept ahead of the S4, B5 I think, not sure on these new fangled chassis numbers, the v6 twin turbo one anyway.
He was at ADI in the afternoon, bright yellow, difficult to miss. He only started doing sprints this year and at the first event he was 10 seconds a drift of our times. He's punching out 450bhp (50% more than us) running on slicks and now starting to shed some weight with a carbon fibre bonnet and plastic windows. He's getting faster, but not fast enough yet, I was still nearly 4 seconds clear in our Classic Audi .

So I took first, Andy got second and we finished the year with a couple of trophies .

Season over, time to get to work on the car now .

[Audi Derek]

Originally Posted by Tim C

So I took first, Andy got second and we finished the year with a couple of trophies .

Season over, time to get to work on the car now .

Its nice to end with a trophy or two..



..

[Tim C]

Got the car off the trailer and took advantage of a photo op. Didn't have much time for positioning, the sun was on it's way . Damn those bins .

[Tim C]

We made the decision to ditch the hydraulics; the mechanical hydraulic pump, bomb and brake servo etc.
Then, in its place, fit a vacuum brake servo and electro/hyraulic pump for the power steering.

Once all the paraphernalia was removed, it left lots of room. In fact I got in there on a few ocassions .



Managed to track down a suitable vacuum servo in the end, which was an equivalent for a later coupe I think.
Only problem being, the pushrod was M12 and much longer than the M10 on the original hyraulic one.
On top of that though, the clevice was longer as well .





So I had to extend the M12 (fine) thread down the rod (once I'd got hold of an M12 x 1.5 die).



And then cut the rod back. Now the distance from the mounting flange to the clevis pin was identical .



With the servo mounted up it left a nice space in the corner by the chassis leg for the hydraulic pump.



There are a few cars around these days that use them, Saxo and 106 for example. I settled on an MR2 one as it's a bit more compact.



Made up a mounting bracket.



And secured in it's new home.



Put steady on the top and had new hydraulic pipe made up to connect to the existing steering rack connection.



Brake servo back in place and at least 5mm clearance from the end of the steering rack to the pump. It was planned, honest .



Just need to plumb from the existing hydraulic fluid reservoir down to the pump and an electrical feed to the pump.
It's supposed to pull about 30A at full load when turning rapidly but only single figures when idleing or not doing too much.
I thought I would use the fuel pump signal to drive a relay to start the pump, but that pulls in as soon as you turn the key (or press the button in our case) putting extra drain on the battery. So I've put in a delay timer so that the pump will start after the engine has started.
The time delay is adjustable and will be a bit of trial and error. The Emerald ECU pulses the fuel pumps for a couple of seconds when the igntion is turned on. So the delay will want to be longer than that, but just long enough so the pump starts soon after a normal engine fire up.

So, this has gone...



To be replaced with...



A net weight loss of 1.5 kg and the weight is now further back against the baulkhead not hanging out on the front of the engine.

Word has is that a mechanical hydraulic pump takes approximately 7 or 8 horsepower and an electric one 3. It all counts .

[Isimmo]

That looks excellent Tim, have you considered including a simple single pole switch on the dash for turning the PAS pump relay on. That way, on paddock start-up you can avoid the current draw of the pump but if the car stalls on stage the 'timer' will be sufficiently quick to allow instant assistance.

[Tim C]

Originally Posted by Isimmo

That looks excellent Tim, have you considered including a simple single pole switch on the dash for turning the PAS pump relay on. That way, on paddock start-up you can avoid the current draw of the pump but if the car stalls on stage the 'timer' will be sufficiently quick to allow instant assistance.

Ahead of you there Ian, but thanks for the input (as always).

I've put a 3 position toggle switch on the dash. Centre off, one way is permenantly on and the other way is to the timer, or auto position.
That way the pump can be disabled if necessary, perhaps for a starting issue. It can also be manually switched on if the timer plays up, or as you say, to provide steering assistance without the engine running. Finally, and hopefully for the majority of the time, be left in the auto position to look after itself.

[Tim C]

Moved this to my thread to stop hijacking Dave's .

Originally Posted by Tim C

Yeah , still got the X relay, not a bad idea. But the pump would then run if you were sat with ignition on and no engine running. As we do when letting it cool down.
Suppose you could use both signals, so it only pulled in once the fuel pump was running and the X relay re-energised.

I can see me fitting a PLC to this car yet .


EDIT - just realised, the X relay drops out when it loses the feed from the ignition switch in the start position. We don't have one anymore, just a toggle switch for ignition and a pushbutton to start.

Originally Posted by darreno'd'

So does your x relay drop out ? has your start button simply recreationted the position 3 (start) of the old ignition switch ? If it does, a nice simple solution could be to trigger the relay for the hydro from the fuel pump, but supply the load from the x relay circuit, then it won't run without both circuits enabled.

That's pretty much what I was trying to suggest. But unfortunately, no the X relay doesn't drop out. It's feed is now just lumped in with the normal ignition feed from the single pole toggle switch on the dashboard .
I'd need a start push button with a normally closed auxilary contact on it to reinstate the X relay circuit. I'll have to look into that .