120 replies to this topic

[Ethel]

diesels have vac pumps for servos sure you can find a belt drive one

[miniboo]

do you really need a servo to be honest?

[koss]

My reference to a servo was on silicon scums idea of using a modern,ish car. It would have to meet the same braking weights on the mot.

[brightsparkz]

Hi,

Sorry not much progress since my last update.










Chairchild: Thats a good point about the drive shafts. Hadn’t thought of that. I have already cut the drive shafts though. What I have done is cut the shafts to length, bored a 10mm hole in both sides, tapered both ends and put a 10mm dia rod in between and welded into the V. it should be strong enough. The sierra diff was 3.5 I think.

Silicone Skum: there is no such thing as a cheap conversion. Its either you do it properly or not at all. You could get a cheap milk float motor and a under powered curtis controller and old flooded batteries but the performance will be C**p and it will probably be a flop. If you go all out and get decent kit the outcome will be better well that’s what I hope! I actually had a job interview with SEV. Didn’t get it though . They get their motors from a company in italy. They had some suitable motors but were a bit heavy.

For the car to be road legal I have added the handbrake facility but not thought about anything else.

Anyone know where I can get a motor driven vacuum pump?


Suren

[chairchild]

how about getting an oil pump from a fiesta, and just connecting it to an electric motor (radiator fan from a ford or something, as they tend to be quite beefy) You'd have to modify the pump by blocking off the pressure regulator, and relief valve and just throwing on a spare filter for ease. Wont be perfect, but it should be quite compact, and should last a fair while - as well as giving a fair bit of vacuum

[Silicon Skum]

how about getting an oil pump from a fiesta, and just connecting it to an electric motor (radiator fan from a ford or something, as they tend to be quite beefy)

Fan motor would be no use, it would overheat far too quickly - they are designed for short duration use. A DC perminant magnet motor would be the best bet, you could pick something up of the internet quite cheaply (something like a 100W 3000RPM electric scooter motor should do).

An oil pump wouldn't create a vacuum, they use a centrifugal impeller to force the liquid oil around, air would just rush straight past the blades. As posted at the top of this page, a belt driven vacuum unit from a diesel engine would be the option to go for.


Brightsparkz:

I know there is no such thing as a cheap conversion.......but you can make use of just about anything if lightly modified and used in the right way.

For the controller, I would either self build or use a ready made controller - depends on the voltage and motor I use. Thinking of keeping the clutch on the gearbox, and only using field weakening on a shunt wound motor to adjust the motor speed (armature directly connected to battery voltage and a soft start controller), motor would idle at a slower RPM at full field current. . Not the most efficient way to do it, but it means I will only have to deal with the field winding amperage - which is FAR less than armature current, so much cheaper controller!

Would be looking at something around a 20hp motor minimum, so should be good for a top end speed of about 50Mph (which will be fine, Motorway and long distance would be out of the question anyway). I was considering using a WarP motor, they are series wound, so would have to use a heavy duty controller to handle the amps needed - unless it could be converted to a shunt wound. Would be damned expensive to have it shiped over from the USA though! That's why I'm tempted to use SEV, they are local and I could save a packet on shiping by picking it up myself.

Batteries are going to be the biggest killer to my funds though - hence the testing with car batteries (much cheaper, but will only last about 15 - 20 cycles of 75% DOD before the plates start to give out). I would want to test it works first, before investing a big lump of cash into batteries.

I have a lot to work out and price up before I do this, but I intend to use the lower cost method that will still give a decent result.

SS

Edited by Silicon Skum, 18 September 2007 - 10:34 PM.

[Ethel]

how about getting an oil pump from a fiesta, and just connecting it to an electric motor (radiator fan from a ford or something, as they tend to be quite beefy)

Fan motor would be no use, it would overheat far too quickly - they are designed for short duration use. A DC perminant magnet motor would be the best bet, you could pick something up of the internet quite cheaply (something like a 100W 3000RPM electric scooter motor should do).

An oil pump wouldn't create a vacuum, they use a centrifugal impeller to force the liquid oil around, air would just rush straight past the blades. As posted at the top of this page, a belt driven vacuum unit from a diesel engine would be the option to go for.


Brightsparkz:

I know there is no such thing as a cheap conversion.......but you can make use of just about anything if lightly modified and used in the right way.

For the controller, I would either self build or use a ready made controller - depends on the voltage and motor I use. Thinking of keeping the clutch on the gearbox, and only using field weakening on a shunt wound motor to adjust the motor speed (armature directly connected to battery voltage and a soft start controller), motor would idle at a slower RPM at full field current. . Not the most efficient way to do it, but it means I will only have to deal with the field winding amperage - which is FAR less than armature current, so much cheaper controller!

Would be looking at something around a 20hp motor minimum, so should be good for a top end speed of about 50Mph (which will be fine, Motorway and long distance would be out of the question anyway). I was considering using a WarP motor, they are series wound, so would have to use a heavy duty controller to handle the amps needed - unless it could be converted to a shunt wound. Would be damned expensive to have it shiped over from the USA though! That's why I'm tempted to use SEV, they are local and I could save a packet on shiping by picking it up myself.

Batteries are going to be the biggest killer to my funds though - hence the testing with car batteries (much cheaper, but will only last about 15 - 20 cycles of 75% DOD before the plates start to give out). I would want to test it works first, before investing a big lump of cash into batteries.

I have a lot to work out and price up before I do this, but I intend to use the lower cost method that will still give a decent result.

SS

couldn't you just clear Argos out of AA NiCads - take 'em back for a refund after a couple of weeks trial

[brightsparkz]

Got myself a mini! Main shell is in good nick so i'm happy. Will be selling off the bits i dont need ie the engine, seats rear subframe, front subframe. will post in the sales section when i have the car.

Not done too much on the drive train. finally mounted the motor though.

Hopefully more updates next week.

[Silicon Skum]

OOOOOH!! progressing nicely!

Looking forward to seeing this with the motor and control gear installed!

SS

[brightsparkz]

Finally got the mini home! Has hardly any rust for a Breg! There is a pic of the worst of the rust. Will probably replace the rear valence. Will be replacing the rear subframe next weekend with my own one so that will be interesting but I will have to get myself rear coil overs before I can do that. Anyone have any going cheap?

Nearly finished the rear subframe, will have to add lots of triangulation as things are a bit bendy at the moment.

Things are progressing nicely

Few questions…

1) Is a GRP front lighter then the standard steel one? I want the lightest option.
2) If I got myself GRP doors would I die if I had a side on crash? Are GRP doors road legal?
3) Do I need to keep that gay red light at the back?

I will be getting rid of the engine, front/rear subframe, fuel tank, exhaust, gear lever mech. Will be selling on ebay next week, PM me if you are interested in any of the bits. The engine has done 77K and is a 998cc, the guy I bought the car off drove the car into his garage and has not moved it till I bought it. When I got it there were bits missing so I could not test the engine. So I’m selling as a non runner.

[chairchild]

GRP will be marginally lighter - it really depends on how you attatch it, and how you make teh brace-bars

Yes, you have to keep the little gay red light I'm afraid - but you could always move it into one of the reverse lights instead :wink:

And AFAIK, there's no reason why GRP doors wouldnt be road-legal (if they're fitted properly and securely of course) But to be honest, you're just as likely to get injured with a steel door in a side-impact as you are with GRP doors - it just means that instead of having shattered glass slice your face open (which would be replaced with perspex I'm guessing?) you'd just have lumps of torn GRP slice you open.....


..and to be honest, I'd rather have the larger chunks of GRP stuck in me, than glass in my eyes/face

[brightsparkz]

Progress!







Will have to put a strut across the rear suspension to stop things twisting. surprised on how thin the steel was!

[Ethel]

You're not mounting the diff that high are you? I was wondering how you'll be off for suspension travel with the shafts going through the rear subby?

note the 3 pin plug does that mean you've solved the battery problem

[Jammy]

I have a feeling if the diff isn't that high then you'd have clearance issues with the bottom of it. And since its RWD then I guess there isn't going to be a conventional rear subby.

[brightsparkz]

There isnt much of a rear subframe. I will be using rear coilovers once i have welded on the mounts to the swing arm.

I hope there wont be a clearance issue, see the new pics and let me know if u think i'm in trouble.





i have a plug and a long lead in case the battery runs out