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PS. The conversion kit is currently £6000 all in and fitted. This cost may well go down if they can sort out a better way of dealing with the wiring. Currently each conversion is almost completely rewired by hand.. [:0]
Chris was talking about using some kind of mutli-plug connector thing and just plugging all the new bit into the original bit which would obviously speed the process up a bit.
Knowing Chris though, I wouldn’t hold your breath on this one! [
]Lotus have already switched to Toyota power (I work there currently!).
Up until now the best car coming out of our factory hasd been the VX220 turbo, I think now the Toyota Elise should be a better bet! [
]Company name is Z-Cars. They did some of the work on my chassis, have been doing BEC stuff for a long while now with background in grasstrack racing.
Website here: https://www.zcars.org.uk/ but no info on the Smarts yet.
I have some pics of the demo car and conversion kit Chris had at the Autosport show recently if anyone is interested..The kit also fits the new Smart roadsters. Having test driven the roadster and also driven GF’s normal Smart, I reckon it’d be best put in the roadster which at least goes round corners to start with! [
]Actually the K is pretty useless once highly tuned (190+bhp) the head gasket is a serious weak point.
Although it’s light it is an old design now – there are much better engines to choose from these days, I wouldn’t even consider a K for anything other than the shopping cars it was intended for.quote:
Originally posted by audimanSaw the XTR2 in a magazine and think it’s a great looking car. Are there any shows on this year where I can see it and others?
Best Kitcar show of the year is Stoneleigh on May Bank holiday weekend. Near Coventry. Most kitcar manufacturers will be there showing all sorts of stuff including the BEC ranges. There are some others but all are smaller than Stoneleigh..
There are quite a few with the engine behind the driver, Radical SR3 and Westfeild XTR2 to name a couple.
Strathcarron re-engineered their cars to run the K series lump I believe before legislation killed the car. I think the molds may have been bought up though as there is a kitcar that looks very similar floating about.
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Originally posted by audimanDeservedly so it seems. How is your project going?
Ok ta – car off the road ATM for a diff swap (amongst other things) to improve the top speed. By-product will also be to reduce the engine RPMs for a given speed which might also make it a bit more road friendly! [
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Originally posted by imperialdataStay with me on this one…..
If they run out of oil when cornering in the car that’s the equivalent of wheelies or stoppies on a bike isn’t it? Speaking purely from an engine orientation point of view here.
Yup, absolutely. I think there are 2 further problems with the car install though.
1) the sumps are often shortened slightly (mine are about 50mm shorter than they were in the bike) so you have a lower volume of oil to start with.
2) For track use you can often find that you will be pulling high G cornering one after the other. In these circumstances, where there are no straights for the oil to restabilise, you can encounter problems. I’m assuming that these corners can go on for longer than you could pull a wheelie or stoppie for. This set of corners will also (obviously!) crop up lap after lap, so the loading on the engine is pretty high – sooner or later you’ll get quick enough and maintain a high enough contiunous lateral G load that the engine gives up.
I have read of bikers pulling wheelies through the gears and having the oil pressure light flickering on in the process. If they were to do that over and over again, the engine would let go, same as the above example in the car. [
]In the car the engines can also often run hotter so the oil gets thinner too – again a bad thing..
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Originally posted by imperialdataI understand there are 2 approaches to twin engine design.
1. Drive the rear wheels with engine (a) and the front wheels with engine (b)
2. Use both engines’ output to drive a common gearbox
How the hell does option 1 work, is it totally reliant on electronic engine management? Seem to remember a split gearshift on a Tiger Seven replica which allowed each engine to be gearchanged separately but there must be more to it than that.
All twin BECs (except the bike engine derived V8s..) still retain the original gearboxes – hence the split gearlevers. This applies to 4WD and RWD variants.
To the best of my knowledge all the twin BECs have a split gearchange like mine. You need this to recover from missed shifts or false neutrals etc..
Option 1) requires an electronic “centre diff” to reduce power to the front wheels in order that the car can turn into corners properly – and is very expensive.
Option 2) requires a “transfer box” to take the output from the 2 bike gearboxes and combine. This box sits just behind the engines, at the front of the transmission tunnel. It has 2 inputs and one output which goes, via a propshaft, to the rear diff. This is cheaper than the electronic centre diff – but still not cheap due to it’s “bespoke” nature.quote:
Originally posted by imperialdataThanks Tim. Why do they prefer R1’s or GSXR’s for twin BEC’s? Are they a particularly small lump?
Yup, physical size and gearbox output location suits mating up to the transfer box which combines the drive.
There are also some twin busa 4wd cars floating about though, so anything’s possible. One is currently for sale with 2x tuned up busa engines + nitrous. Bit of a monster by all accounts! []quote:
Can you explain the advantages of drysumping and how it is achieved?Erm, not in much detail TBH.. Basically though becasue the car doesn’t lean in cornering like the bike does (and cos the engine sits N-S rather than E-W anyway) high speed cornering can cause oil surge. This then leads to starvation of oil from the pickup pipe and you end up running bearings and introducing your conrods to the outside world via the block! [
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Some engines seem particularly prone to this – Blackbird for one – and others seem relatively unaffected – like the Blade. Tendancy is to run drysumps on more expensive engines like the Busa, but not on the cheaper ones. Mainly cos the drysump costs IRO £1000 and you can get 2 cheap engines for that!
Halfway house is an accusump, but they can cause problems of their own it would seem, so best to stump up for full drysumping on a track car if you run either an expensive or an oilsurge-prone engine.quote:
Originally posted by redgearAre there any magazines for this type of car/bike hybrid?
Not specifically. But the general kit car press covers BECs every now and again, they’re getting much more popular now!
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Originally posted by audimanAre there any cars using 3 engines?
Don’t think so. But it wouldn’t be imposible given a suitable chassis in which they could all physically fit.
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Originally posted by imperialdataWould you say that the R1 lends itself to car layout. I know that angles are critical and often the sump has to be modified because the engine sits at a different angle to when it was in the bike.
Yep, very much so. Main thing is that it is being adopted by a few people so there is experience of fitting them. Sidecar racers use them in the same orientation as in the car (I think), sumps are available anyway! Also the gearbox output is high and in a very good position to get a good propshaft run without nasty angles (and therefore vibration – a major problem in bike engine cars (BECs))
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What’s your engine of choice (if money were no object)?Money no object for a road based single BEC would be a busa. For a track based one a drysumped busa (drysumping is 100% essential for a track busa BEC).
For a twin, current fave is the R1 or GSXR1000, probably erring towards the GSXR1000 cos there are a couple of them running as twins already.HTH! [
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