vw aircooled engine on 126 box?

[mic]

is it possibe?  a little 1300cc might give it poke if it fits  [-/

[baked one]

ive been talking to a few people and ive heard the vw beetle engine and gearbox fit but i dont think the 126 gearbox can take the power from the 1.3 also with a conversion plate you can hook up most vw engines onto the beetle gearbox   

[mic]

But you wouldn't need a conversion plate if it was a 1.3 engine + box from a beetle?! And that fits? Just needs mounts for it?

[landyman]

everyone is searching for this holy grail more bhp in a easy package to fit the 126, trying not to fall into biva trap designed to stop us all having fun. afterall nobody wants to crash their pride and joy or injure themselves due to dodgy engineering.I think it has been toyed with in another post I think k75 bmw sounds viable with the early carb option or k 1000 with a modified boot lid rear/crossmember these parts would not need a modified monocoque.I don't want to go that fast but I weigh in at 20 stone the 24bhp engine has to work hard and you notice when you have passengers!
buzzing people downhill with the wind behind you is great fun but embarassing when they come past on the uphill.

[hudsonhenry]

The BIVA is the thing to really consider when thinking about these kind of conversions, as I mentioned to Ralph on another thread, any modification to the shell that can't be classified as a legitimate repair or an accepted (by an officially recognised club) period modification (fitting a Rover V8 into an MGB for example) will land you in line for a BIVA if you swap the engine and one or two other major components as well.

With a liquid cooled engine you have to put a radiator somewhere, on my 500/1108 conversion I put the radiator in the front between the two panels with holes for airflow either side and pipes running from front to back. I am in the process of building another one but an looking into mounting the radiator in such a way that I do not have to modify the shell. There are a few options I'm looking at, I have a front spoiler radiator housing that is fitted to the 1108(like the ones fitted to the 600 Abarths), it was just covering the holes but I could get a radiator made to fit it with a couple of small fans. I'm also looking at mounting two small radiators in the space under the rear swing arms with some scoops to catch the air running under the car or mounting the rad and fans in the engine bay over the engine (it ls lower than the air cooled) with ducting taking the air from under the car.

The VW gearbox is huge, I'm not sure if you will get it to fit without cutting the shell and ending up in BIVA.

The other way of looking at it is to build a car with the BIVA in mind, it will be issued a Q plate but you can make it as radical as you like (as long as you comply to the standards). Once its tested and approved you will always be legal, even if the later ban modified cars.

To see what you can do with a 500 have a look at my website www.retro500.com

Nigel

[Matt S]

just reading through this thread i spotted this...........

k75 bmw sounds viable with the early carb option

I hate to rain on the idea BUT K series BMW bikes never came with carb, they were all fuel injection from day one.

[landyman]

was misled on carb option apparently they made a bike with 75 name but was a boxer aircooled on carbs after looking into the idea it could still be viable using k series wiring loom and ecu have got hold of workshop manual just incase i see a cheap bike for sale.

[Dom]

http://cgi.ebay.co.uk/BMW-K75-1993-MODEL-ENGINE-COMPLETE_W0QQitemZ110467715417QQcmdZViewItemQQptZUK_Motorcycle_Parts?hash=item19b8639159#ht_524wt_831

[fightingtorque]

I'm still pretty keen on the K75 or K100 engine idea.  I have the haynes manual.

The engine has a separate balance shaft undere the crank, which is also the output shaft, i.e. the clutch and flywheel are on it.  It is gear driven from the crank, so rotates in the opposite direction.  When I found this out I thought this would mean the direction is wrong but once I got the Haynes manual I have found that the engine rotation direction is opposite to normal engines (anticlockwise from front) so by the time you get to this otput shaft the direction will be correct.

Gearbox durability is probably an issue if you use it hard, but I think if it is driven sensibly especially in the first two gears it should be ok, after all people are having good results with 1108 fire engine from what I hear.

K100 bikes were going for as little as 500 quid on ebay in the run up to christmas but seem to be fetching a little more now.  I found a guy whoe sells the engines for <200, although you need to add the starter, alternator, throttle bodies etc.   Anyway, when I get time I might go and see this guy and do some taper measuring to see if its even feasible.


a

[fightingtorque]

I met a Dutch guy last week who has a K75 with about 240k km on it, owned since new.  So  if looked after, these engines should be durable.

I don't know whether oil surge will be an issue in cornering, bikes lean into corners but cars don't.  Should be ok.

Generator output might be limited if you are planning to run lots of lights, cooling fans, wipers, big audio etc.

The engine management system on the bikes is an old analogue computer, very old tech, uses a moving flap airflow meter.  I think it would be best to convert to an aftermarket ecu.

It's still on my fantasy list right now, better I concentrate on getting the car back on the road first, there are only a couple of things that need doing to it but there are so many other things to do..........building a  car port, new kitchen, kids, puppy, wife, other cars............ and spending next two weeks in china......

[hudsonhenry]

We looked at the K75 option before deciding on a 1108 Fiat fire engine. We went as far as buying a complete engine. The problem we found was that the engine casing of K75 engine has a fairly deep recess to the flywheel (you can see here: http://www.flickr.com/photos/burnszilla/148302704/ ). We decided that the best answer to this would be to machine up an top-hat shaped flywheel to bridge the gap between where the K75 flywheel is mounted and the gearbox. We even bought a big steel billet to machine up but then decided to go the easier Fire route.

There may well be other options but that along with the need to add an ecu put us off. Cracking engine though, I wish you the best of luck.

Nigel

[fightingtorque]

I had also seen that this might be a problem.  Basically what would normally be the bellhousing part of the gearbox is on the engine.  Looks like it is actually the same casting as the crankcase?
Can't remember whether the bellhousing on the fiat transmission is a separate casting that could be removed?

Went as far as buying an engine...... I take it you don't have it gathering dust still?

[hudsonhenry]

Went as far as buying an engine...... I take it you don't have it gathering dust still?

I've got a feeling we scrapped it  but I will have a look at the weekend.

Nigel

[fightingtorque]

look what we have here.....

http://www.flickr.com/photos/-eu/3646989645/

That's a 500 bay with the K75, no room for the fourth cylinder.

Engine looks high, because of the output shaft being below the crank, puts the whole thing upwards.  I was hoping it would go in a Bis, albeit perhaps with a raised engine compartment cover, but this looks very high up.