Monty the Rwd R1 engined tarmac eating Minus by Alburglar

8 minute(s) of a 160 minute read

I'm thinking more like another £4 relay rigged up to my neutral light, so that when I'm in neutral the relay cuts off any feeds from the rectifier charging the extra battery. Or preferably wiring the relay so that the push button is activated, the relay cuts off the feed from the rectifier to the extra battery.

I will try it first with a fully charged, completely standalone battery to check it works, and then with it being charged by the rectifier, with, as koss suggested, a switch to break the link to the rectifier to test that theory. If that works then hopefully my relay idea will work.

Thanks for the brainstorming everyone, much appreciated.

12-11-2011

Well I had a few minutes today. I wired a second battery completey seperately and charged it up. I hit the reverse button and.....
...well nothing happened, the engine stays running but there isn't enough oomph to turn the wheels backwards. I'm gonna try with the power cap in as well as the battery and wire it all in properly when the relay I ordered turns up. If it doesn't work with the cap, then I don't know what else to try apart from bigger batteries and caps?

I did a couple of other little jobs too. I set up the acewell digidash. First you're supposed to figure this out:
Tire Diameter (inch) x 25.4(mm/inch) x 3.1416 = wheel circumference (in mm).
Which for me with 13's should end up being 1037mm.- Should be, because the instructions give a figure chart for various wheel sizes, the smallest at 15 is 1197 and every one above that is +80mm. ie 16 is 1277, etc.
You have to press and hold both buttons on the dash to enter setup mode. You then flick through each setup stage like the clock, then set the rpm that you want it to warn you to shift at. It's default was 12500, and I wasn't exactly sure, so I left it at that. Then I set the SPC (Signals Per Crank rotation) setting to 0.5, because R1 carb has a waisted spark ignition system, it gives off twice as many signals per rotation as other non-waisted sparks engines would. This sorted my rpm reading double, so I was very happy with that.
Next I entered my weird circumference figure in, this is to collobrate the speedo. We'l have to wait and see if that works on the road.
Then I set mph instead of kph.
Sorted!

12-13-2011

Ok I'll change it to that then.
I took for another drive and the speedo works, the revs are spot on and now so is my idle.
and as for the reverse, we have progress.
I charged the battery for ages, added the power cap rigged up a seperate feed to rectifier via an on off switch in the off position.

I hit the button and I reversed very slowly for about 5 seconds before it ran out of juice. Rubbish.
Battery is 600amp and cap is 2 farad. I can buy a 35 farad cap and a1600amp battery, but I am wondering, is it worth it? We'll see
I ran the car, and checked the main battery with meter - 13.80 volts from rectifier with feed to 2nd battery off. 13.40 volts with feed to second battery on. Not brilliant, but its a start. I will upgrade to thicker wiring and try again.
I also have added this cigarette lighter, hidden under px side of dash.

It's so I can add a battery conditioner for when cars not in use and satnav to make sure speedo is accurate.

Oh yeah, I forgot to add that I got some speed up on the last run and I have NO BRAKES!!!!!
Metro master cylinder is going on, next job!

12-15-2011

I found this lithium battery, which doesn't suffer from bad 'memory' loss like normal lead acid batteries:
http://vamosbatteries.com/
but it's not really powerfull enough and has poor performance in cold temperatures, so apparently a optima yellow top battery is gonna be the best bet. The YTS 4.2 is 870 amps but still 765 amps up to -18C and ways a whopping 19.5kilos. It is designed to be discharged and recharged too. There is a yts 5.5 with better power CCA (EN -18°C): 975 amps MCA (BCI 0°C): 1125 amps, but it weighs a tremendous 26.5 kilos!
http://www.optimabat...owtop-s-55.html
I'm waiting for responses on wether the power cap is realistically very usefull or not, it looks like 2.0 farad is a drop in the ocean for a starter motor.

12-16-2011

The kit comes with starter ring (lightened flywheel attached to the sprocket) and starter motor, you have to wire it / make it work. I'm sure lots of people have had the same problems, but have ditched the reverse. For those that have kept it, it isn't covered very well in the build threads. I think the gripper diff that I have in mine has a lot of drag in it(unless its *******), which doesn't help.
Yes the cap is supposed to store enough power for it to soak up the initial start, I'm not convinced that it helped much.

It seems an average starter is about 1.4hp so 1kw ish. 1kW at 12v is about 83amps. 5 minutes is 1/12th kw/h. Therfore, in theroy, I would need an 83Ah battery to run for an hours worth of use (excluding the big current draw from initial start-up). To get 5 minutes use out of it is 1/12th of 83 which is 6.9Ah, which is feck all, but the battery needs to have the big numbers for the initial startup.
So the optima yellow top 4.2 is 55Ah and is designed for starting and heavy use - so I'm gonna go for that when funds allow, it being nearly chrimbo and all.

The man from vamos batteries, that make the lithium battery, has been very helpful. His current battery is 12Ah and he is developing an 18Ah one. The 12ah weighs 2.3 kgs and is pretty small, so a bank of 3 18Ah's lithiums would be great if money was no object. They drop in power to all most nothing when cold tho (around 0 degrees). But it's pretty warm in my mini with the engine going!

12-17-2011

I am leaning towards buying two lithium battery's 12Ah and 500A each and trying it, and then adding another in parrallel if that doesn't work! It's a toss up between weight and cost, but if I add a whole lump of weight to the car, it kind of defeats the object of it. But at £260 a battery that is expensive. However, I'm building a car that I can jump in on a sunny sunday and take for a blast along the b roads and that will be equally at home on a track day. So the expense seems justified to save weight. But if the gripper diff is what demands the battery oomph in 3 point turns, should I fit a Quaife ATB?- Then one lithium battery would probably be adequate. And that could be achieved for a little bit more money.
Decisions!!!!!

12-23-2011

Right, ******** to batteries, I got started on the brakes today. The metro split line non-servo master cylinder is not exactly a straight swap.
First, you have to make the push rod hole bigger, and as you can see I have chopped some of the standard bracket away to (the braket was later ditched but oh well)

The push rod was a much easier issue than I was anticipating, because you can use the standard mini push rod, albeit with a10mm approx spacer, which in this case I just rounded off a nyloc nut on the bench grinder and inserted it into the tube on the master cylinder:

The mini pushrod then sits within the tube and slides all the way up the, and with the spacer inside it is a perfect match up to get the clevis pin through on the pedal box.

Apart from the fact that the metro cylinder can't bolt down fully yet because the metro reservoir doesn't clear the mini one. Which is why the bracket got ditched, in order to lower the mini m/c and I will make a spacer to raise the metro m/c a couple of mm. But I did manage to plumb the brakes in with bits I had lying around and it does clear the bonnet!

The thread on one of the studs striped tho, which is annoying, but I mightneed longer ones anyway once the spacer is in place.

Forgot to add, that I had to drill holes to suit the mini stud pattern too!